NASA celebrates the 40th anniversary of Earth Day on the National Mall in Washington beginning Saturday, April 17. Included in the events is the 'NASA Village,' which contains three domed tents, and will highlight the use of NASA science and technology to advance knowledge and awareness about our home planet and sustain our environment. The NASA Science Tent which will host exhibits and hands-on demonstrations. The NASA Cinema Tent will feature multimedia presentations by NASA scientists and others. The NASA Technology Tent will present exhibits and demonstrations on a wide range of NASA environmental technologies.
Wednesday, April 21, 2010
Wednesday, April 14, 2010
Einstein's theory is still the best game in town
Two new and independent studies have put Einstein's General Theory of Relativity to the test like never before. These results, made using NASA's Chandra X-ray Observatory, show Einstein's theory is still the best game in town.Each team of scientists took advantage of extensive Chandra observations of galaxy clusters, the largest objects in the Universe bound together by gravity. One result undercuts a rival gravity model to General Relativity, while the other shows that Einstein's theory works over a vast range of times and distances across the cosmos.
The first finding significantly weakens a competitor to General Relativity known as "f(R) gravity".
"If General Relativity were the heavyweight boxing champion, this other theory was hoping to be the upstart contender," said Fabian Schmidt of the California Institute of Technology in Pasadena, who led the study. "Our work shows that the chances of its upsetting the champ are very slim."
In recent years, physicists have turned their attention to competing theories to General Relativity as a possible explanation for the accelerated expansion of the universe. Currently, the most popular explanation for the acceleration is the so-called cosmological constant, which can be understood as energy that exists in empty space. This energy is referred to as dark energy to emphasize that it cannot be directly detected.
In the f(R) theory, the cosmic acceleration comes not from an exotic form of energy but from a modification of the gravitational force. The modified force also affects the rate at which small enhancements of matter can grow over the eons to become massive clusters of galaxies, opening up the possibility of a sensitive test of the theory.
Schmidt and colleagues used mass estimates of 49 galaxy clusters in the local universe from Chandra observations, compared them with theoretical model predictions and studies of supernovas, the cosmic microwave background, and the large-scale distribution of galaxies.
They found no evidence that gravity is different from General Relativity on scales larger than 130 million light years. This limit corresponds to a hundred-fold improvement on the bounds of the modified gravitational force's range that can be set without using the cluster data.
"This is the strongest ever constraint set on an alternative to General Relativity on such large distance scales," said Schmidt. "Our results show that we can probe gravity stringently on cosmological scales by using observations of galaxy clusters."
The reason for this dramatic improvement in constraints can be traced to the greatly enhanced gravitational forces acting in clusters as opposed to the universal background expansion of the universe. The cluster-growth technique also promises to be a good probe of other modified gravity scenarios, such as models motivated by higher- dimensional theories and string theory.
A second, independent study also bolsters General Relativity by directly testing it across cosmological distances and times. Up until now, General Relativity had been verified only using experiments from laboratory to Solar System scales, leaving the door open to the possibility that General Relativity breaks down on much larger scales.
To probe this question, a group at Stanford University compared Chandra observations of how rapidly galaxy clusters have grown over time to the predictions of General Relativity. The result is nearly complete agreement between observation and theory.
“Einstein's theory succeeds again, this time in calculating how many massive clusters have formed under gravity's pull over the last five billion years,” said David Rapetti of the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) at Stanford University and SLAC National Accelerator Laboratory, who led the new study. “Excitingly and reassuringly, our results are the most robust consistency test of General Relativity yet carried out on cosmological scales."
Rapetti and his colleagues based their results on a sample of 238 clusters detected across the whole sky by the now-defunct ROSAT X-ray telescope. These data were enhanced by detailed mass measurements for 71 distant clusters using Chandra, and 23 relatively nearby clusters using ROSAT, and combined with studies of supernovas, the cosmic microwave background, the distribution of galaxies and distance estimates to galaxy clusters.
Galaxy clusters are important objects in the quest to understand the Universe as a whole. Because the observations of the masses of galaxy clusters are directly sensitive to the properties of gravity, they provide crucial information. Other techniques such as observations of supernovas or the distribution of galaxies measure cosmic distances, which depend only on the expansion rate of the universe. In contrast, the cluster technique used by Rapetti and his colleagues measure in addition the growth rate of the cosmic structure, as driven by gravity.
"Cosmic acceleration represents a great challenge to our modern understanding of physics," said Rapetti's co-author Adam Mantz of NASA's Goddard Space Flight Center in Maryland. "Measurements of acceleration have highlighted how little we know about gravity at cosmic scales, but we're now starting to push back our ignorance."
The paper by Fabian Schmidt was published in Physics Review D, Volume 80 in October 2009 and is co-authored by Alexey Vikhlinin of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, and Wayne Hu of the University of Chicago, Illinois. The paper by David Rapetti was recently accepted for publication in the Monthly Notices of the Royal Astronomical Society and is co- authored by Mantz, Steve Allen of KIPAC at Stanford and Harald Ebeling of the Institute for Astronomy in Hawaii.
NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge, Mass.
Tuesday, March 30, 2010
Exploring the Carina Nebula by Touch
The Hubble Space Telescope's dramatic glimpse of the Carina Nebula, a gigantic cloud of dust and gas bustling with star-making activity, is a glorious feast for the eyes. Energetic young stars are sculpting a fantasy landscape of bubbles, valleys, mountains, and pillars. Now this celestial fantasyland has been brought into view for people who cannot explore the image by sight.
Max Mutchler, a research and instrument scientist at the Space Telescope Science Institute in Baltimore, and Noreen Grice, president of You Can Do Astronomy LLC and author of several tactile astronomy books, have created a touchable image of the Carina Nebula that is engaging for everyone, regardless of their visual ability.
The 17-by-11-inch color image is embossed with lines, slashes, and other markings that correspond to objects in the giant cloud, allowing visually impaired people to feel what they cannot see and form a picture of the nebula in their minds. The image's design is also useful and intriguing for sighted people who have different learning styles.
"The Hubble image of the Carina Nebula is so beautiful, and it illustrates the entire life cycle of stars," says Mutchler, who, along with Grice, unveiled the tactile Carina image in January 2010, at the American Astronomical Society meeting in Washington, D.C. "I thought that people who are visually impaired should be able to explore it and learn from it, too."
Located 7,500 light-years from Earth, the nebula is a 3-million-year-old gigantic cloud where thousands of stars are cycling through the stages of stellar life and death. The nebula is 300 light-years wide, but Hubble captured a 50-light-year-wide view of its central region.
A Hubble education and public outreach grant allowed Mutchler to produce the special image. The grant is part of his Hubble archival research project to create complete mosaics of a huge collection of individual Carina Nebula images taken by Hubble (http://archive.stsci.edu/prepds/carina/). Mutchler made 300 copies of the tactile image and will distribute them to organizations that serve the visually impaired, including state schools and libraries for the blind and the National Federation of the Blind in Baltimore, Md.
When Mutchler decided to make a tactile Carina Nebula image last year, he immediately called his friend Grice, who is a pioneer in designing tactile astronomy images for the blind.
But Grice says the nebula image is so visually rich, it posed a challenge to design a textured image that conveys its beauty and complexity.
"When I first looked at the image, I didn't know what to focus on," she recalls. "In order to translate the image into a tactile image, I had to make certain that I understood the individual features that make up the image. There was so much to see."
She spent a couple of hours on the telephone with Mutchler, who gave her a guided tour of the nebula. Then she parsed astronomy books, looking for other views of the nebula. One feature, in particular, gave her some trouble. It was the Keyhole Nebula. Grice couldn't see how the shape in the image resembled a keyhole. Finally, she came across a 1950s image of Carina, and suddenly, she got it. The name referred to the shape of an old-fashioned "skeleton" key. Some visually impaired children who have touched the image say the feature actually resembles a foot, Grice says.
Choosing which features to show on the textured image also posed a challenge. Grice says she relied on a lesson she learned from her first NASA tactile astronomy book of Hubble images called "Touch the Universe": less is more.
"Convey just enough to get the idea," she says. "Then provide some Braille text that explains the science and describes the scene. A picture that is jammed with too many tactile details is very overwhelming for the mind's eye."
Grice used the Keyhole Nebula as the focal point and added other important features suggested by Mutchler to tell the story of stellar life and death, such as pillars of gas and dust that harbor infant stars, a cluster of young stars called Trumpler 14, and a massive, unstable star, Eta Carinae, that is near the end of its life.
The pair then developed a tactile code identifying the raised features and wrote a short guided tour that provides more information on the highlighted on the features. The guide and an audio tour of the nebula are on a special Web page called "The Tactile Carina Nebula" (http://amazing-space.stsci.edu/tactile-carina/), on Amazing Space, the Space Telescope Science Institute's education Web site.
A stable of seasoned tactile astronomy evaluators, including Vivian Hoette, the education outreach coordinator of the University of Chicago's Yerkes Observatory in Williams Bay, Wis., and Ben Wentworth, a retired teacher from the Colorado School for the Blind in Colorado Springs, Colo., helped test several prototypes of the image. One such evaluation place was the Youth Slam, held in the summer of 2009 in College Park, Md. The National Federation of the Blind coordinated the event to promote careers in math, engineering, and science.
One of the biggest surprises from their testing was the image size. Grice and Mutchler originally thought that a large (almost 6-foot-wide) or medium-sized (3-foot-wide) tactile image would be appropriate for students. The children who sampled the image, however, preferred the much smaller 11-by-17-inch image.
"Many students felt lost with the larger prototype versions because certain objects were separated by empty spaces," Grice says. "However, the smaller version allowed hands to easily track from one object to another."
Adds Hoette, one of the evaluators: "The smaller size gives them enough details so they can get the big picture, and then they can read the science behind it in Braille text, or they can listen to the audio tour on 'The Tactile Carina' Web page while they are touching the image."
The Grice-Mutchler partnership has worked so well that the duo hopes to produce more tactile Hubble images. "It would be great to build up a catalogue of these images for the visually impaired," Mutchler says.
The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute conducts Hubble science operations. The institute is operated for NASA by the Association of Universities for Research in Astronomy, Inc. in Washington, D.C.
Max Mutchler, a research and instrument scientist at the Space Telescope Science Institute in Baltimore, and Noreen Grice, president of You Can Do Astronomy LLC and author of several tactile astronomy books, have created a touchable image of the Carina Nebula that is engaging for everyone, regardless of their visual ability.
The 17-by-11-inch color image is embossed with lines, slashes, and other markings that correspond to objects in the giant cloud, allowing visually impaired people to feel what they cannot see and form a picture of the nebula in their minds. The image's design is also useful and intriguing for sighted people who have different learning styles.
"The Hubble image of the Carina Nebula is so beautiful, and it illustrates the entire life cycle of stars," says Mutchler, who, along with Grice, unveiled the tactile Carina image in January 2010, at the American Astronomical Society meeting in Washington, D.C. "I thought that people who are visually impaired should be able to explore it and learn from it, too."
Located 7,500 light-years from Earth, the nebula is a 3-million-year-old gigantic cloud where thousands of stars are cycling through the stages of stellar life and death. The nebula is 300 light-years wide, but Hubble captured a 50-light-year-wide view of its central region.
A Hubble education and public outreach grant allowed Mutchler to produce the special image. The grant is part of his Hubble archival research project to create complete mosaics of a huge collection of individual Carina Nebula images taken by Hubble (http://archive.stsci.edu/prepds/carina/). Mutchler made 300 copies of the tactile image and will distribute them to organizations that serve the visually impaired, including state schools and libraries for the blind and the National Federation of the Blind in Baltimore, Md.
When Mutchler decided to make a tactile Carina Nebula image last year, he immediately called his friend Grice, who is a pioneer in designing tactile astronomy images for the blind.
But Grice says the nebula image is so visually rich, it posed a challenge to design a textured image that conveys its beauty and complexity.
"When I first looked at the image, I didn't know what to focus on," she recalls. "In order to translate the image into a tactile image, I had to make certain that I understood the individual features that make up the image. There was so much to see."
She spent a couple of hours on the telephone with Mutchler, who gave her a guided tour of the nebula. Then she parsed astronomy books, looking for other views of the nebula. One feature, in particular, gave her some trouble. It was the Keyhole Nebula. Grice couldn't see how the shape in the image resembled a keyhole. Finally, she came across a 1950s image of Carina, and suddenly, she got it. The name referred to the shape of an old-fashioned "skeleton" key. Some visually impaired children who have touched the image say the feature actually resembles a foot, Grice says.
Choosing which features to show on the textured image also posed a challenge. Grice says she relied on a lesson she learned from her first NASA tactile astronomy book of Hubble images called "Touch the Universe": less is more.
"Convey just enough to get the idea," she says. "Then provide some Braille text that explains the science and describes the scene. A picture that is jammed with too many tactile details is very overwhelming for the mind's eye."
Grice used the Keyhole Nebula as the focal point and added other important features suggested by Mutchler to tell the story of stellar life and death, such as pillars of gas and dust that harbor infant stars, a cluster of young stars called Trumpler 14, and a massive, unstable star, Eta Carinae, that is near the end of its life.
The pair then developed a tactile code identifying the raised features and wrote a short guided tour that provides more information on the highlighted on the features. The guide and an audio tour of the nebula are on a special Web page called "The Tactile Carina Nebula" (http://amazing-space.stsci.edu/tactile-carina/), on Amazing Space, the Space Telescope Science Institute's education Web site.
A stable of seasoned tactile astronomy evaluators, including Vivian Hoette, the education outreach coordinator of the University of Chicago's Yerkes Observatory in Williams Bay, Wis., and Ben Wentworth, a retired teacher from the Colorado School for the Blind in Colorado Springs, Colo., helped test several prototypes of the image. One such evaluation place was the Youth Slam, held in the summer of 2009 in College Park, Md. The National Federation of the Blind coordinated the event to promote careers in math, engineering, and science.
One of the biggest surprises from their testing was the image size. Grice and Mutchler originally thought that a large (almost 6-foot-wide) or medium-sized (3-foot-wide) tactile image would be appropriate for students. The children who sampled the image, however, preferred the much smaller 11-by-17-inch image.
"Many students felt lost with the larger prototype versions because certain objects were separated by empty spaces," Grice says. "However, the smaller version allowed hands to easily track from one object to another."
Adds Hoette, one of the evaluators: "The smaller size gives them enough details so they can get the big picture, and then they can read the science behind it in Braille text, or they can listen to the audio tour on 'The Tactile Carina' Web page while they are touching the image."
The Grice-Mutchler partnership has worked so well that the duo hopes to produce more tactile Hubble images. "It would be great to build up a catalogue of these images for the visually impaired," Mutchler says.
The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute conducts Hubble science operations. The institute is operated for NASA by the Association of Universities for Research in Astronomy, Inc. in Washington, D.C.
Saturday, March 27, 2010
Operation IceBridge Off to a Winning Start in Greenland
Hello and a warm welcome to all blog readers from the IceBridge team here at Thule Air Base in northern Greenland. After taking off on Sunday night from NASA Dryden's Aircraft Operations Facility in Palmdale, Calif., the NASA DC-8 arrived at Thule Airbase on Monday afternoon. Both the aircraft and science teams have done an incredible job in setting up operations in record time here in Thule.
The moon and sunrise are visible over the Arctic Ocean during the flight from Palmdale, Calif., to Thule, Greenland. Credit: Michael StudingerWe were able to take off for an eight-hour science flight on Tuesday morning to survey the sea ice in the Arctic Ocean north of Ellesmere Island. Wednesday's science flight was targeted at several glaciers north of Thule. Some of the glaciers have been surveyed for the first time last year and we are back this year to monitor the changes that have occurred since last spring. We begin the day with flying over a small glacier called Heilprin Glacier. We are very early in the season and the sun is just above the horizon in the morning hours, illuminating the coast of Greenland with its frozen fjords, icebergs and glaciers in a beautiful light.
The sun is very low and only barely above the horizon at the beginning of the third science flight, creating beautiful illumination of the cost of Greenland with its frozen fjords, icebergs and glaciers. Credit: Michael StudingerAfter an hour of flying we begin to fly a grid pattern in the catchment area of Petermann Glacier to measure the thickness of the ice with a radar system from the University of Kansas. These data will be used as input for computer models that will allow us to better predict how the Greenland ice sheet will respond to environmental changes in the Arctic.
We continue our flight by repeating two survey lines along Petermann Glacier that have been surveyed several years before. The scenery with the steep sidewalls is spectacular. We can see huge meltwater channels on the surface that will be filled with water running down the glacier when the Arctic melt season starts in a few months.
The IceBridge crew fly down Petermann Glacier in northern Greenland with NASA's DC-8 aircraft. Credit: Michael Studinger
After completing the flight lines over the Petermann Glacier we turn back towards Thule Airbase and measure the ice surface elevation with a laser altimeter along a track that has been measured many times by NASA's ICESat satellite. We are heading back to Thule Airbase to land before the tower and airfield close for the day.
At the end of a day of glacier flying, Saunders Island -- a small table mountain just outside Thule -- can be seen during the approach to Thule Air Base. Credit: Michael Studinger
We have had an incredibly successful start of the 2010 Arctic campaign. We have been able to collect LVIS laser data along the transit from California to Greenland and have been flying 3 days in a row collecting huge amounts of data. A storm system here in Thule has forced us today to stay on the ground and everyone is catching up with sleep and data processing. With a little bit of luck we hope to fly the DC-8 again on Friday. Thanks to all the aircraft and science teams, the staff at Thule Air Base, and many people back home who have made such an incredible start of the IceBridge 2010 campaign possible!
Wednesday, March 24, 2010
It’s spring time on Mars
A Burst of Spring
Spring has sprung on Mars, bringing with it the disappearance of carbon dioxide ice (dry ice) that covers the north polar sand dunes. In spring, the sublimation of the ice (going directly from ice to gas) causes a host of uniquely Martian phenomena.
In this image streaks of dark basaltic sand have been carried from below the ice layer to form fan-shaped deposits on top of the seasonal ice. The similarity in the directions of the fans suggests that they formed at the same time, when the wind direction and speed was the same. They often form along the boundary between the dune and the surface below.
Spring has sprung on Mars, bringing with it the disappearance of carbon dioxide ice (dry ice) that covers the north polar sand dunes. In spring, the sublimation of the ice (going directly from ice to gas) causes a host of uniquely Martian phenomena.
In this image streaks of dark basaltic sand have been carried from below the ice layer to form fan-shaped deposits on top of the seasonal ice. The similarity in the directions of the fans suggests that they formed at the same time, when the wind direction and speed was the same. They often form along the boundary between the dune and the surface below.
NASA’s Mars Rover Getting Smarter
NASA's Mars Exploration Rover Opportunity, now in its seventh year on Mars, has a new capability to make its own choices about whether to make additional observations of rocks that it spots on arrival at a new location.
Software uploaded this winter is the latest example of NASA taking advantage of the twin Mars rovers' unanticipated longevity for real Martian test drives of advances made in robotic autonomy for future missions.
Now, Opportunity's computer can examine images that the rover takes with its wide-angle navigation camera after a drive, and recognize rocks that meet specified criteria, such as rounded shape or light color. It can then center its narrower-angle panoramic camera on the chosen target and take multiple images through color filters.
"It's a way to get some bonus science," said Tara Estlin of NASA's Jet Propulsion Laboratory, Pasadena, Calif. She is a rover driver, a senior member of JPL's Artificial Intelligence Group and leader of development for this new software system.
The new system is called Autonomous Exploration for Gathering Increased Science, or AEGIS. Without it, follow-up observations depend on first transmitting the post-drive navigation camera images to Earth for ground operators to check for targets of interest to examine on a later day. Because of time and data-volume constraints, the rover team may opt to drive the rover again before potential targets are identified or before examining targets that aren't highest priority.
The first images taken by a Mars rover choosing its own target show a rock about the size of a football, tan in color and layered in texture. It appears to be one of the rocks tossed outward onto the surface when an impact dug a nearby crater. Opportunity pointed its panoramic camera at this unnamed rock after analyzing a wider-angle photo taken by the rover's navigation camera at the end of a drive on March 4. Opportunity decided that this particular rock, out of more than 50 in the navigation camera photo, best met the criteria that researchers had set for a target of interest: large and dark.
"It found exactly the target we would want it to find," Estlin said. "This checkout went just as we had planned, thanks to many people's work, but it's still amazing to see Opportunity performing a new autonomous activity after more than six years on Mars."
Opportunity can use the new software at stopping points along a single day's drive or at the end of the day's drive. This enables it to identify and examine targets of interest that might otherwise be missed.
"We spent years developing this capability on research rovers in the Mars Yard here at JPL," said Estlin. "Six years ago, we never expected that we would get a chance to use it on Opportunity."
The developers anticipate that the software will be useful for narrower field-of-view instruments on future rovers.
Other upgrades to software on Opportunity and its twin, Spirit, since the rovers' first year on Mars have improved other capabilities. These include choosing a route around obstacles and calculating how far to reach out a rover's arm to touch a rock. In 2007, both rovers gained the know-how to examine sets of sky images to determine which ones show clouds or dust devils, and then to transmit only the selected images. The newest software upload takes that a step further, enabling Opportunity to make decisions about acquiring new observations.
The AEGIS software lets scientists change the criteria it used for choosing potential targets. In some environments, rocks that are dark and angular could be higher-priority targets than rocks that are light and rounded, for example.
This new software system has been developed with assistance from NASA's Mars Exploration Rover Project and with funding from the New Millennium Program, the Mars Technology Program, the JPL Interplanetary Network Development Program, and the Intelligent Systems Program. The New Millennium Program tests advanced technology in space flight. JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover Project for the NASA Science Mission Directorate, Washington.
Software uploaded this winter is the latest example of NASA taking advantage of the twin Mars rovers' unanticipated longevity for real Martian test drives of advances made in robotic autonomy for future missions.
Now, Opportunity's computer can examine images that the rover takes with its wide-angle navigation camera after a drive, and recognize rocks that meet specified criteria, such as rounded shape or light color. It can then center its narrower-angle panoramic camera on the chosen target and take multiple images through color filters.
"It's a way to get some bonus science," said Tara Estlin of NASA's Jet Propulsion Laboratory, Pasadena, Calif. She is a rover driver, a senior member of JPL's Artificial Intelligence Group and leader of development for this new software system.
The new system is called Autonomous Exploration for Gathering Increased Science, or AEGIS. Without it, follow-up observations depend on first transmitting the post-drive navigation camera images to Earth for ground operators to check for targets of interest to examine on a later day. Because of time and data-volume constraints, the rover team may opt to drive the rover again before potential targets are identified or before examining targets that aren't highest priority.
The first images taken by a Mars rover choosing its own target show a rock about the size of a football, tan in color and layered in texture. It appears to be one of the rocks tossed outward onto the surface when an impact dug a nearby crater. Opportunity pointed its panoramic camera at this unnamed rock after analyzing a wider-angle photo taken by the rover's navigation camera at the end of a drive on March 4. Opportunity decided that this particular rock, out of more than 50 in the navigation camera photo, best met the criteria that researchers had set for a target of interest: large and dark.
"It found exactly the target we would want it to find," Estlin said. "This checkout went just as we had planned, thanks to many people's work, but it's still amazing to see Opportunity performing a new autonomous activity after more than six years on Mars."
Opportunity can use the new software at stopping points along a single day's drive or at the end of the day's drive. This enables it to identify and examine targets of interest that might otherwise be missed.
"We spent years developing this capability on research rovers in the Mars Yard here at JPL," said Estlin. "Six years ago, we never expected that we would get a chance to use it on Opportunity."
The developers anticipate that the software will be useful for narrower field-of-view instruments on future rovers.
Other upgrades to software on Opportunity and its twin, Spirit, since the rovers' first year on Mars have improved other capabilities. These include choosing a route around obstacles and calculating how far to reach out a rover's arm to touch a rock. In 2007, both rovers gained the know-how to examine sets of sky images to determine which ones show clouds or dust devils, and then to transmit only the selected images. The newest software upload takes that a step further, enabling Opportunity to make decisions about acquiring new observations.
The AEGIS software lets scientists change the criteria it used for choosing potential targets. In some environments, rocks that are dark and angular could be higher-priority targets than rocks that are light and rounded, for example.
This new software system has been developed with assistance from NASA's Mars Exploration Rover Project and with funding from the New Millennium Program, the Mars Technology Program, the JPL Interplanetary Network Development Program, and the Intelligent Systems Program. The New Millennium Program tests advanced technology in space flight. JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover Project for the NASA Science Mission Directorate, Washington.
Thursday, March 18, 2010
See Big Red Glowing Spot on Jupiter
New thermal images from powerful ground-based telescopes show swirls of warmer air and cooler regions never seen before within Jupiter's Great Red Spot, enabling scientists to make the first detailed interior weather map of the giant storm system.
The observations reveal that the reddest color of the Great Red Spot corresponds to a warm core within the otherwise cold storm system, and images show dark lanes at the edge of the storm where gases are descending into the deeper regions of the planet. These types of data, detailed in a paper appearing in the journal Icarus, give scientists a sense of the circulation patterns within the solar system's best-known storm system.
"This is our first detailed look inside the biggest storm of the solar system," said Glenn Orton, a senior research scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., who was one of the authors of the paper. "We once thought the Great Red Spot was a plain old oval without much structure, but these new results show that it is, in fact, extremely complicated."
Sky gazers have been observing the Great Red Spot in one form or another for hundreds of years, with continuous observations of its current shape dating back to the 19th century. The spot, which is a cold region averaging about 110 Kelvin (minus 260 degrees Fahrenheit) is so wide about three Earths could fit inside its boundaries.
The thermal images obtained by giant 8-meter (26-foot) telescopes used for this study -- the European Southern Observatory's Very Large Telescope in Chile, the Gemini Observatory telescope in Chile and the National Astronomical Observatory of Japan's Subaru telescope in Hawaii -- have provided an unprecedented level of resolution and extended the coverage provided by NASA's Galileo spacecraft in the late 1990s. Together with observations of the deep cloud structure by the 3-meter (10-foot) NASA Infrared Telescope Facility in Hawaii, the level of thermal detail observed from these giant observatories is comparable to visible-light images from NASA's Hubble Space Telescope for the first time.
One of the most intriguing findings shows the most intense orange-red central part of the spot is about 3 to 4 Kelvin (5 to 7 degrees Fahrenheit) warmer than the environment around it, said Leigh Fletcher, the lead author of the paper, who completed much of the research as a postdoctoral fellow at JPL and is currently a fellow at the University of Oxford in England. This temperature differential might not seem like a lot, but it is enough to allow the storm circulation, usually counter-clockwise, to shift to a weak clockwise circulation in the very middle of the storm. Not only that, but on other parts of Jupiter, the temperature change is enough to alter wind velocities and affect cloud patterns in the belts and zones.
"This is the first time we can say that there's an intimate link between environmental conditions -- temperature, winds, pressure and composition - and the actual color of the Great Red Spot," Fletcher said. "Although we can speculate, we still don't know for sure which chemicals or processes are causing that deep red color, but we do know now that it is related to changes in the environmental conditions right in the heart of the storm."
Unlocking the secrets of Jupiter's giant storm systems will be one of the targets for infrared spacecraft observations from future missions including NASA's Juno mission.
The observations reveal that the reddest color of the Great Red Spot corresponds to a warm core within the otherwise cold storm system, and images show dark lanes at the edge of the storm where gases are descending into the deeper regions of the planet. These types of data, detailed in a paper appearing in the journal Icarus, give scientists a sense of the circulation patterns within the solar system's best-known storm system.
"This is our first detailed look inside the biggest storm of the solar system," said Glenn Orton, a senior research scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif., who was one of the authors of the paper. "We once thought the Great Red Spot was a plain old oval without much structure, but these new results show that it is, in fact, extremely complicated."
Sky gazers have been observing the Great Red Spot in one form or another for hundreds of years, with continuous observations of its current shape dating back to the 19th century. The spot, which is a cold region averaging about 110 Kelvin (minus 260 degrees Fahrenheit) is so wide about three Earths could fit inside its boundaries.
The thermal images obtained by giant 8-meter (26-foot) telescopes used for this study -- the European Southern Observatory's Very Large Telescope in Chile, the Gemini Observatory telescope in Chile and the National Astronomical Observatory of Japan's Subaru telescope in Hawaii -- have provided an unprecedented level of resolution and extended the coverage provided by NASA's Galileo spacecraft in the late 1990s. Together with observations of the deep cloud structure by the 3-meter (10-foot) NASA Infrared Telescope Facility in Hawaii, the level of thermal detail observed from these giant observatories is comparable to visible-light images from NASA's Hubble Space Telescope for the first time.
One of the most intriguing findings shows the most intense orange-red central part of the spot is about 3 to 4 Kelvin (5 to 7 degrees Fahrenheit) warmer than the environment around it, said Leigh Fletcher, the lead author of the paper, who completed much of the research as a postdoctoral fellow at JPL and is currently a fellow at the University of Oxford in England. This temperature differential might not seem like a lot, but it is enough to allow the storm circulation, usually counter-clockwise, to shift to a weak clockwise circulation in the very middle of the storm. Not only that, but on other parts of Jupiter, the temperature change is enough to alter wind velocities and affect cloud patterns in the belts and zones.
"This is the first time we can say that there's an intimate link between environmental conditions -- temperature, winds, pressure and composition - and the actual color of the Great Red Spot," Fletcher said. "Although we can speculate, we still don't know for sure which chemicals or processes are causing that deep red color, but we do know now that it is related to changes in the environmental conditions right in the heart of the storm."
Unlocking the secrets of Jupiter's giant storm systems will be one of the targets for infrared spacecraft observations from future missions including NASA's Juno mission.
Monday, March 15, 2010
Crew Members get ready for Return to Earth from Space Station
Soaring high over the Earth in the International Space Station, the astronauts and cosmonauts of the Expedition 22 crew began a new week Monday, the final week in space for two of their number.
Commander Jeff Williams and Flight Engineer Maxim Suraev will depart the station Thursday aboard the Soyuz TMA-16 spacecraft. They will undock from the orbiting complex and take a three-and-a-half-hour ride that will culminate in a parachute-assisted landing on the steppe of Kazakhstan early that morning.
Williams and Suraev began their final week in orbit by testing the Soyuz spacecraft’s motion control system and recharging the satellite telephone they will carry with them in the unlikely event that they land off course in the barren landing region and need to contact search and recovery forces. They also spent three hours going over procedures for their homeward flight with specialists on the ground.
As members of the Expedition 21 and 22 crews, Williams and Suraev will have spent 169 days in space. Including his time on the Expedition 13 and STS-101 crews, this will give Williams a total of 362 days in space, placing him fourth on the all-time U.S. list of space travelers behind Peggy Whitson with 377 days, Mike Foale with 374 and Mike Fincke with 366. Williams will be 26th on the all-time endurance list for all space travelers.
Expedition 22 Flight Engineers Soichi Noguchi, T.J. Creamer and Oleg Kotov will continue their stay on the station becoming the new Expedition 23 crew. Kotov will become the new station commander when the departing Williams enters the Soyuz vehicle and closes the hatch.
On April 4, Expedition 23 will expand to a six-member crew. Arriving in the Soyuz TMA-18 spacecraft will be new station crew members Alexander Skvortsov, Tracy Caldwell Dyson and Mikhail Kornienko.
On April 7, space shuttle Discovery is scheduled to arrive for a thirteen day mission to supply the station with new science racks and ammonia tanks. STS-131 will feature three spacewalks and the delivery of the Leonardo Multi-Purpose Logistics Module.
In preparation for the joint spacewalks to be performed during STS-131, Creamer and Noguchi packed up equipment for Discovery to return to Earth and Noguchi performed maintenance on the cooling loops in the U.S. spacesuits housed in the station’s Quest airlock.
Controllers on the ground operated Canadarm2, the station’s robotic arm, to remove the Special Purpose Dextrous Manipulator, known as Dextre, from the Mobile Base System (MBS) on the complex’s truss structure. Tuesday they will move it to the outside of the Destiny laboratory in order to make the MBS available for use during STS-131.
Commander Jeff Williams and Flight Engineer Maxim Suraev will depart the station Thursday aboard the Soyuz TMA-16 spacecraft. They will undock from the orbiting complex and take a three-and-a-half-hour ride that will culminate in a parachute-assisted landing on the steppe of Kazakhstan early that morning.
Williams and Suraev began their final week in orbit by testing the Soyuz spacecraft’s motion control system and recharging the satellite telephone they will carry with them in the unlikely event that they land off course in the barren landing region and need to contact search and recovery forces. They also spent three hours going over procedures for their homeward flight with specialists on the ground.
As members of the Expedition 21 and 22 crews, Williams and Suraev will have spent 169 days in space. Including his time on the Expedition 13 and STS-101 crews, this will give Williams a total of 362 days in space, placing him fourth on the all-time U.S. list of space travelers behind Peggy Whitson with 377 days, Mike Foale with 374 and Mike Fincke with 366. Williams will be 26th on the all-time endurance list for all space travelers.
Expedition 22 Flight Engineers Soichi Noguchi, T.J. Creamer and Oleg Kotov will continue their stay on the station becoming the new Expedition 23 crew. Kotov will become the new station commander when the departing Williams enters the Soyuz vehicle and closes the hatch.
On April 4, Expedition 23 will expand to a six-member crew. Arriving in the Soyuz TMA-18 spacecraft will be new station crew members Alexander Skvortsov, Tracy Caldwell Dyson and Mikhail Kornienko.
On April 7, space shuttle Discovery is scheduled to arrive for a thirteen day mission to supply the station with new science racks and ammonia tanks. STS-131 will feature three spacewalks and the delivery of the Leonardo Multi-Purpose Logistics Module.
In preparation for the joint spacewalks to be performed during STS-131, Creamer and Noguchi packed up equipment for Discovery to return to Earth and Noguchi performed maintenance on the cooling loops in the U.S. spacesuits housed in the station’s Quest airlock.
Controllers on the ground operated Canadarm2, the station’s robotic arm, to remove the Special Purpose Dextrous Manipulator, known as Dextre, from the Mobile Base System (MBS) on the complex’s truss structure. Tuesday they will move it to the outside of the Destiny laboratory in order to make the MBS available for use during STS-131.
Endeavour Brings Tranquility
Backdropped by the blackness of space, space shuttle Endeavour was photographed by the Expedition 22 crew as the shuttle approached the International Space Station during STS-130 rendezvous and docking operations on Feb. 9, 2010. The Tranquility node can be seen in the shuttle's payload bay.
Monday, March 08, 2010
Alternative Renewable Energy Crops in Space
What if space held the key to producing alternative energy crops on Earth? That's what researchers are hoping to find in a new experiment on the International Space Station.The experiment, National Lab Pathfinder-Cells 3, is aimed at learning whether microgravity can help jatropha curcas plant cells grow faster to produce biofuel, or renewable fuel derived from biological matter. Jatropha is known to produce high quality oil that can be converted into an alternative energy fuel, or biofuel.
By studying the effects of microgravity on jatropha cells, researchers hope to accelerate the cultivation of the plant for commercial use by improving characteristics such as cell structure, growth and development. This is the first study to assess the effects of microgravity on cells of a biofuel plant.
"As the search for alternate energy sources has become a top priority, the results from this study could add value for commercialization of a new product,” said Wagner Vendrame, principal investigator for the experiment at the University of Florida in Homestead. "Our goal is to verify if microgravity will induce any significant changes in the cells that could affect plant growth and development back on Earth."
Launched on space shuttle Endeavour’s STS-130 mission in February, cell cultures of jatropha were sent to the space station in special flasks containing nutrients and vitamins. The cells will be exposed to microgravity until they return to Earth aboard space shuttle Discovery's STS-131 mission targeted for April.
For comparison studies of how fast the cultures grow, a replicated set of samples are being maintained at the University of Florida's Tropical Research and Education Center in Homestead.
"Watching the space shuttle go up carrying a little piece of my work is an indescribable experience," said Vendrame. "Knowing that my experiment could contribute to creating a sustainable means for biofuel production on Earth, and therefore making this a better world adds special value to the work."
Thursday, March 04, 2010
NASA’s International Space Station Program Wins 2009 Collier Trophy
The International Space Station Program has won the 2009 Collier Trophy, which is considered the top award in aviation. The National Aeronautic Association bestows the award annually to recognize the greatest achievement in aeronautics or astronautics in America.“We are honored to receive this prestigious award,” said Bill Gerstenmaier, associate administrator for NASA’s Space Operations Mission Directorate. “We're proud of our past achievements to build and operate the space station, and we're excited about the future- there's a new era ahead of potential groundbreaking scientific research aboard the station."
The International Space Station is a joint project of five space agencies and 15 countries that is nearing completion and will mark the 10th anniversary of a continuous human presence in orbit later this year. The largest and most complicated spacecraft ever built, the space station is an international, technological and political achievement that represents the latest step in humankind’s quest to explore and live in space.
Designated as a national laboratory by Congress in the 2005 NASA Authorization Act, the space station provides a research platform that takes advantage of the microgravity conditions 220 miles above the Earth’s surface across a wide variety of fields, including human life sciences, biological science, human physiology, physical and materials science, and Earth and space science.
Upon completion of assembly later this year, the station’s crew and its U.S., European, Japanese and Russian laboratory facilities will expand the pace of space-based research to unprecedented levels. Nearly 150 experiments are currently under way on the station, and more than 400 experiments have been conducted since research began nine years ago. These experiments already are leading to advances in the fight against food poisoning, new methods for delivering medicine to cancer cells and the development of more capable engines and materials for use on Earth and in space.
The international partner agencies – NASA, the Canadian Space Agency, the European Space Agency, the Japan Aerospace Exploration Agency and the Russian Federal Space Agency – provide control centers and support teams that train and launch crews to the station, provide support for systems operations and coordinate the on-orbit research 24 hours a day, 7 days a week, 365 days a year.
Now supporting a multicultural crew of six, the station has a mass of almost 800,000 pounds and a habitable volume of more than 12,000 cubic feet – approximately the size of a five-bedroom home, and uses state-of-the-art systems to generate solar electricity, recycle nearly 85 percent of its water and generate much of its own oxygen supply. Nearly 190 humans have visited the space station, which is now supporting its 22nd resident crew.
Boeing is the prime contractor, responsible for design, development, construction and integration of the ISS.
The award will be formally presented to the International Space Station Program team on May 13. The award is named for Robert J. Collier, a publisher who commissioned it in 1910 with the intent to encourage the U.S. aviation community to strive for excellence and achievement in aeronautic development. Past winners include the B-52 Program, the Surveyor Moon Landing Program, the Boeing 747 and the F-22. Other past honorees include the crews of Apollo 11 and Apollo 8, the Mercury 7.
Tuesday, March 02, 2010
The Crab Nebula - result of a supernova
The Crab Nebula, the result of a supernova noted by Earth-bound chroniclers in 1054 A.D., is filled with mysterious filaments that are are not only tremendously complex, but appear to have less mass than expelled in the original supernova and a higher speed than expected from a free explosion. The Crab Nebula spans about 10 light-years. In the nebula's very center lies a pulsar: a neutron star as massive as the Sun but with only the size of a small town. The Crab Pulsar rotates about 30 times each second.
Monday, March 01, 2010
NASA And NOAA Ready GOES-P Satellite for March 3 Launch
NASA's GOES-P meteorological satellite is lifted into the mobile service tower at Launch Complex 37 on Cape Canaveral Air Force Station. NASA's GOES-P meteorological satellite is lifted into the mobile service tower at Launch Complex 37 on Cape Canaveral Air Force Station.
Workers install NASA's GOES-P meteorological satellite onto the Delta IV stages already in place in the mobile service tower at Launch Complex 37 on Cape Canaveral Air Force Station. Workers install NASA's GOES-P meteorological satellite onto the Delta IV stages already in place in the mobile service tower at Launch Complex 37 on Cape Canaveral Air Force Station. Photo Credit: NASA/Jack Pfaller
› Larger Image GREENBELT, Md. -- NASA is preparing to launch the NOAA Geostationary Operational Environmental Satellite-P (GOES-P) from Space Launch Complex 37 at the Cape Canaveral Air Force Station, Fla. The launch is targeted for March 2, during a launch window from 6:19 to 7:19 p.m. EST.
"GOES are the backbone of NOAA's severe weather forecasts, monitoring fast-changing conditions in the atmosphere that spawn hurricanes, tornadoes, floods and other hazards," said Steve Kirkner, GOES program manager at NASA's Goddard Space Flight Center, Greenbelt, Md.
GOES-P is the third and final spacecraft to be launched in the GOES N Series of geostationary environmental weather satellites. The GOES satellites continuously provide observations of more than 50 percent of the Earth, including the continental United States, providing weather monitoring and forecast operations and a continuous and reliable stream of environmental information and severe weather warnings.
In addition to weather forecasting on Earth, a key instrument onboard GOES-P, the Solar X-Ray Imager (SXI), will help NOAA continue monitoring solar conditions.
"The SXI is improving our forecasts and warnings for solar disturbances, protecting billions of dollars worth of commercial and government assets in space and on the ground, and lessening the brunt of power surges for the satellite-based electronics and communications industry," said Tom Bodgan, director of NOAA's Space Weather Prediction Center (SWPC) in Boulder, Colo.
GOES-P joins a system of weather satellites that provide timely environmental information to meteorologists and the public. The GOES system provides data used to graphically display the intensity, path and size of storms. Early warning of impending severe weather enhances the public's ability to take shelter and protect property.
GOES-P will be launched on board a United Launch Alliance Delta IV (4, 2) launch vehicle under a FAA commercial license. The satellite will be turned over to NASA after the successful checkout is completed by Boeing Space and Intelligence Systems, El Segundo Calif.
Currently, NOAA operates GOES-12, (GOES East) and GOES-11 (GOES-West.) In late April, NOAA will activate GOES-13 to replace GOES-12 and will drift eastward from 105 degrees West longitude to 75 degrees West longitude. NOAA plans to move GOES-12 to 60 degrees West longitude to provide coverage for South America as part of the Global Earth Observing System of Systems (GEOSS). NASA handed over GOES-14, launched last June, to NOAA on December 14, 2009. It will remain in normal mode at the 105W storage longitude to provide operational X-ray Sensor coverage to NOAA's SWPC.
Once in orbit GOES-P will be designated GOES-15, checked out and then stored on-orbit and ready for activation should one of the operational GOES satellites degrade or exhaust their fuel.
NOAA manages the GOES program, establishes requirements, provides all funding and distributes environmental satellite data for the United States. NASA Goddard procures and manages the design, development and launch of the satellites for NOAA on a cost reimbursable basis. Boeing Space and Intelligence Systems built GOES-P.
Workers install NASA's GOES-P meteorological satellite onto the Delta IV stages already in place in the mobile service tower at Launch Complex 37 on Cape Canaveral Air Force Station. Workers install NASA's GOES-P meteorological satellite onto the Delta IV stages already in place in the mobile service tower at Launch Complex 37 on Cape Canaveral Air Force Station. Photo Credit: NASA/Jack Pfaller
› Larger Image GREENBELT, Md. -- NASA is preparing to launch the NOAA Geostationary Operational Environmental Satellite-P (GOES-P) from Space Launch Complex 37 at the Cape Canaveral Air Force Station, Fla. The launch is targeted for March 2, during a launch window from 6:19 to 7:19 p.m. EST.
"GOES are the backbone of NOAA's severe weather forecasts, monitoring fast-changing conditions in the atmosphere that spawn hurricanes, tornadoes, floods and other hazards," said Steve Kirkner, GOES program manager at NASA's Goddard Space Flight Center, Greenbelt, Md.
GOES-P is the third and final spacecraft to be launched in the GOES N Series of geostationary environmental weather satellites. The GOES satellites continuously provide observations of more than 50 percent of the Earth, including the continental United States, providing weather monitoring and forecast operations and a continuous and reliable stream of environmental information and severe weather warnings.
In addition to weather forecasting on Earth, a key instrument onboard GOES-P, the Solar X-Ray Imager (SXI), will help NOAA continue monitoring solar conditions.
"The SXI is improving our forecasts and warnings for solar disturbances, protecting billions of dollars worth of commercial and government assets in space and on the ground, and lessening the brunt of power surges for the satellite-based electronics and communications industry," said Tom Bodgan, director of NOAA's Space Weather Prediction Center (SWPC) in Boulder, Colo.
GOES-P joins a system of weather satellites that provide timely environmental information to meteorologists and the public. The GOES system provides data used to graphically display the intensity, path and size of storms. Early warning of impending severe weather enhances the public's ability to take shelter and protect property.
GOES-P will be launched on board a United Launch Alliance Delta IV (4, 2) launch vehicle under a FAA commercial license. The satellite will be turned over to NASA after the successful checkout is completed by Boeing Space and Intelligence Systems, El Segundo Calif.
Currently, NOAA operates GOES-12, (GOES East) and GOES-11 (GOES-West.) In late April, NOAA will activate GOES-13 to replace GOES-12 and will drift eastward from 105 degrees West longitude to 75 degrees West longitude. NOAA plans to move GOES-12 to 60 degrees West longitude to provide coverage for South America as part of the Global Earth Observing System of Systems (GEOSS). NASA handed over GOES-14, launched last June, to NOAA on December 14, 2009. It will remain in normal mode at the 105W storage longitude to provide operational X-ray Sensor coverage to NOAA's SWPC.
Once in orbit GOES-P will be designated GOES-15, checked out and then stored on-orbit and ready for activation should one of the operational GOES satellites degrade or exhaust their fuel.
NOAA manages the GOES program, establishes requirements, provides all funding and distributes environmental satellite data for the United States. NASA Goddard procures and manages the design, development and launch of the satellites for NOAA on a cost reimbursable basis. Boeing Space and Intelligence Systems built GOES-P.
Wednesday, February 24, 2010
Space shuttle Endeavor's Mission specialist onboard
Floating just below the International Space Station, astronaut Nicholas Patrick put some finishing touches on the newly installed cupola space windows last week. Patrick was a mission specialist onboard the space shuttle Endeavor's recently completed STS-130 mission to the ISS.
Monday, February 22, 2010
Space Shuttle Endeavour Completes Mission, Lands at KSC
Shuttle Launch Integration Manager Mike Moses said that space shuttle Endeavour's landing capped off a flawless mission. "The crew did an outstanding job," Moses said, referring to the complex task of installing Tranquility and its seven-windowed cupola to the International Space Station. "The landing today went as smooth as you can hope for -- by the numbers."Moses wrapped up his remarks about the STS-130 mission by saying, "It was an outstanding mission -- I can't be happier with the success we had and look forward to repeating that on our next mission."
Shuttle Launch Director Mike Leinbach was extremely pleased with Endeavour's condition."One of the most magical things we get to do here at Kennedy Space Center is walk around the orbiter after a mission from space. She looks really, really good," Leinbach said.
Leinbach also congratulated Norm Knight and his team in the Mission Control Center at NASA's Johnson Space Center in Houston for a job well done.
Space shuttle Endeavour is home after two weeks in space, having delivered the final U.S. module and a "room with a view" to the International Space Station. STS-130 Commander George Zamka guided Endeavour to a landing at the Kennedy Space Center's Shuttle Landing Facility at 10:20 p.m. EST, to wrap up a 5.7 million mile mission.
Zamka, pilot Terry Virts and Mission Specialists Kathryn Hire, Stephen Robinson, Nicholas Patrick and Robert Behnken left behind more than 36,000 pounds of hardware that included the Tranquility Node 3 and the unique cupola providing a 360-degree view through seven windows.
Behnken and Patrick conducted three spacewalks during the mission totaling 18 hours, 14 minutes. That brings the totals for station assembly to 140 spacewalks and more than 873 hours.
Wednesday, February 17, 2010
Termite Battles May simplify Evolution of Social Insects
Natural selection argues for small biological changes that yield greater chances of survival and successful reproduction. Yet, that process does not square well with the evolution of social insects, particularly when their colonies can have over a million non-reproductive members.A new study of termites may have the answer for such an evolutionary question, first posed by Charles Darwin nearly 150 years ago: How does natural selection produce insect "worker" and "soldier" offspring who never reproduce, find mates or start their own colonies?
Apparently, the answer is because for offspring, there is no place like home.
"This question about the evolution of social behavior among insects really intrigued me," said lead researcher and University of Maryland evolutionary biologist Barbara Thorne, who has spent nearly 30 years pursuing the answer.
"Social insects are extremely successful and dominant in many different habitats all over the world, yet we don't understand how this thriving but complex colony structure evolved. It's why I got involved in these studies when I was a young graduate student."
Thorne's recent research, funded in part by the National Science Foundation (NSF), puts forth a novel theory that it was more advantageous for early termite offspring to stay at home and help their parents than risk dangerous attempts at creating independent colonies away from the nest where they would be more susceptible to predators. The termite youngsters had the best opportunity to take over the reproductive throne when their parents were killed by neighbors.
"The incentive to remain home with their siblings and inherit their parents' estate could provide a missing link to the evolution of sterility among social insects," Thorne said.
Thorne and her colleagues Philip Johns and Ken Howard, both now at Bard College, and fellow Maryland colleagues Nancy Breisch and Anahi Rivera, staged meetings between colonies of neighboring Dampwood termites--the most primitive living termites with traits similar to hypothesized ancestors--and also analyzed the termites' genetic markers.
Her team's research shows that when two neighboring termite families within the same log meet, they battle, often leading to the deaths of one or both families' kings and queens.This paves the way for replacement "junior" kings and queens to develop from either or both colonies' worker offspring. In other words, sterile termites can become reproducers when their parents are killed, becoming the main progenitors for the colony.
Pheromones produced by healthy kings and queens normally suppress gonad development in "helper" classes, and when the kings and queens die, the pheromones disappear or diminish. As a result, suppression lifts and nonrelated, "sterile," helper offspring from both colonies are able to become new "reproductives" and assume the throne.
"Assassination of founding kings and queens may have driven young termite offspring to remain as non-reproducing workers in their birth colonies," said Thorne. Rather than risk dangerous attempts at initiating independent colonies outside the nest, remaining at home may have given them a better opportunity to become reproducers.
It also turns out that hundreds of king and queen founding pairs simultaneously colonize the same dead tree, giving the insects greater opportunity to meet and battle their neighbors. When kings and queens are killed, termites from the unrelated families join forces and cooperate in a larger, stronger group in which new reproductive termites can emerge from either or both colonies' worker ranks. Termites from the two families may even interbreed.
Because these young colonies are relatively small, the offspring--that remain as helpers in their parents' nests--have a reasonable chance of inheriting the family's resources and becoming reproductive termites.
"The merged colony also has a size advantage in its next battle with a neighbor," Thorne said. "Thus, both unrelated families benefit following colony encounters."
"Ants, bees and wasps also have highly social colonies with queens and sterile helpers, but they have an unusual genetic system that complicates study of their social origins," Thorne said. "Termites have both kings and queens, and their colony organization is amazingly convergent with the ants, bees and wasps, yet they (termites) evolved completely independently and have a more normal genetic system. Termites haven't received a lot of attention from evolutionary biologists, yet their case may reveal some fundamental principles."
The primitive living termite featured in the research, genus Zootermopsis, shares social, developmental and habitat characteristics with ancient ancestors, and thus serves as a model system to draw inferences regarding how highly social behavior evolved in these insects 140 million years ago. Once primitive termites had an incentive to stay at home in their parents' nest due to the possibility of early or "accelerated" inheritance, that behavior became fixed and over evolutionary time, termite social behavior passed through what Harvard biologist Edward O. Wilson describes as the "point of no return."
"These findings demonstrate how ecological factors could have promoted the evolution of social organization by accelerating and enhancing direct fitness opportunities of helper offspring, rendering relatedness favoring kin selection less critical," Thorne said.
For more info visit http://www.nsf.gov/
Monday, February 15, 2010
Climate change has a major impact on tropical lizards and their ecosystems
Lizards are ectotherms--animals whose body temperatures vary with surrounding temperatures. Ectotherms, which account for the largest population of animals on Earth, are found in the highest concentrations in tropical areas.Since the 1940s, scientists have known that lizards regulate their body temperatures by moving between sun and shade. Less well understood has been tropical lizards' adaptability to changes in the temperature and availability of shade in their environment.
A study conducted by Raymond Huey of the University of Washington and colleagues was designed to improve our understanding of these variables. The Huey study, funded by the National Science Foundation (NSF), involved:
• Analyzing previous climate data and comparing it to lizard body temperatures in the Amazon rainforest between 1985 and 2005 and in the Caribbean in the 1970s. "In the 1970s a bunch of us were running around the Caribbean with thermometers taking lizard body temperatures for reasons totally unrelated to climate warming," Huey said. "But we can use our data from a third of a century ago as a baseline to now predict how lizards at different latitudes would respond to climate change."
• Measuring the "fitness" of tropical lizards and moderate-climate lizards in the laboratory, i.e., how fast they run at various temperatures.
Huey and his team found that in the laboratory, tropical lizards remained at their peak fitness level within narrow ranges of temperatures that reflected average temperatures in tropical climates. When temperatures exceeded these average temperatures even slightly, the speed at which the lizards ran decreased and their responses became relatively sluggish.
Huey's team also found that the average temperature in the Caribbean forest has risen three and a half degrees, from 80 degrees Fahrenheit to 83.5 degrees F. The rise in temperature has caused these lizards to become heat stressed and not able to function as well. This is important because the more slowly lizards move, the more vulnerable they are to predators; this vulnerability may reduce the sizes of their populations.
Why are tropical lizards apparently more sensitive to temperature increases than moderate-climate lizards? Probably because lizards that live in topical forests, which are consistently hot and humid both day and night almost year-round, are only exposed to slight temperature changes and have not evolved to adapt to significant temperature increases. Therefore, lizards living in tropical forests are relatively sensitive to temperature increases caused by climate change, and their fitness levels decrease as temperatures rise.
By contrast, in many higher latitude climates, lizards experience a wide range of temperatures on a daily and seasonal basis. For example, daytime temperatures in desert regions in the southwest United States may soar well over 100 degrees F, and then dip into the 60s during evening hours. Because lizards living in these areas have evolved to adapt to such relatively extreme temperature changes, they may adapt to increases in temperature caused by climate change relatively easily. Therefore, their fitness levels are less affected by climate warming than are tropical lizards' levels.
Furthermore, because tropical lizards rely on the shade of the forest to help them regulate their body temperature, changes in the canopy structure caused by climate change may indirectly affect their ability to cool down.
Effects of temperature rise will ultimately affect all of us, according to Laurie Vitt, one of Huey's fellow researchers on the project.
Thursday, February 11, 2010
Permafrost could be Global Warming's Ticking Time Bomb
The terrain of the North Slope of Alaska is not steep, but Andrew Jacobson still has difficulty as he hikes along the spongy tundra, which is riddled with rocks and masks multitudes of mosquitoes.
Jacobson, a professor of earth and planetary sciences at Northwestern University, extracts soil and water samples in search of clues to one of global warming's biggest ticking time bombs: the melting of permafrost.
Permafrost, or frozen ground, covers approximately 20 to 25 percent of the land-surface area in the northern hemisphere, and is estimated to contain up to 1,600 gigatons of carbon, primarily in the form of organic matter. (One gigaton is equivalent to 1 billion tons.)By comparison, the atmosphere now contains around 850 gigatons of the element as carbon dioxide.
"Permafrost historically has served as a carbon sink, largely isolating carbon from participating in the carbon cycle," says Jacobson, whose research is funded by the National Science Foundation (NSF) and the David and Lucile Packard Foundation. "However, global warming could transform the Arctic into a new carbon source by accelerating the rate of permafrost melting. This undoubtedly would have a dramatic effect on the global carbon cycle."
Jacobson says the key concern is that permafrost carbon will oxidize to carbon dioxide as melting accelerates, causing a positive feedback to global warming. A vicious cycle is created as a warmer climate facilitates more carbon release, which in turn favors more warming.
So Jacobson and his colleagues collect river water and soil samples near NSF's Toolik Long-Term Ecological Research station, approximately 250 kilometers (km)--155 miles--north of the Arctic Circle. The Dalton Highway--built as a supply road to support the Trans-Alaska Pipeline System--provides the only access to the site.
"Planning constitutes a large part of our day--looking at maps, figuring out where to go and how to get there," he laughs. "Fieldwork is typically fraught with vehicle problems, poor roads and bad weather. One thing you can always count on is that every expedition is exciting."
While a logical first step for modeling global warming is quantifying carbon flow, unresolved complexities surrounding the Arctic carbon cycle make it difficult to create models for that element.
Jacobson and his team take a complementary approach by analyzing naturally occurring isotopes of other elements, such as calcium and strontium, which track permafrost melting and therefore provide insight into carbon release.
Initial data show that rivers and permafrost have distinctly different calcium and strontium isotope compositions.When permafrost thaws during the summer and melts into rivers, the rivers show calcium and strontium isotope compositions that approach those for permafrost. Jacobson hypothesizes that in a warmer world, the permafrost signature in rivers will be more pronounced for longer periods of time.
Changes in the isotope composition of rivers can relate to changes in the release of carbon. So the calcium and strontium isotope composition of Arctic rivers can track the impact of warming on permafrost stability and carbon dioxide release.
"The ultimate goal is to establish a baseline to which future changes can be compared," Jacobson says. "Several years from now, we can compare real changes to model predictions and improve our understanding of how the system works."
http://www.nsf.gov
Jacobson, a professor of earth and planetary sciences at Northwestern University, extracts soil and water samples in search of clues to one of global warming's biggest ticking time bombs: the melting of permafrost.
Permafrost, or frozen ground, covers approximately 20 to 25 percent of the land-surface area in the northern hemisphere, and is estimated to contain up to 1,600 gigatons of carbon, primarily in the form of organic matter. (One gigaton is equivalent to 1 billion tons.)By comparison, the atmosphere now contains around 850 gigatons of the element as carbon dioxide.
"Permafrost historically has served as a carbon sink, largely isolating carbon from participating in the carbon cycle," says Jacobson, whose research is funded by the National Science Foundation (NSF) and the David and Lucile Packard Foundation. "However, global warming could transform the Arctic into a new carbon source by accelerating the rate of permafrost melting. This undoubtedly would have a dramatic effect on the global carbon cycle."
Jacobson says the key concern is that permafrost carbon will oxidize to carbon dioxide as melting accelerates, causing a positive feedback to global warming. A vicious cycle is created as a warmer climate facilitates more carbon release, which in turn favors more warming.
So Jacobson and his colleagues collect river water and soil samples near NSF's Toolik Long-Term Ecological Research station, approximately 250 kilometers (km)--155 miles--north of the Arctic Circle. The Dalton Highway--built as a supply road to support the Trans-Alaska Pipeline System--provides the only access to the site.
"Planning constitutes a large part of our day--looking at maps, figuring out where to go and how to get there," he laughs. "Fieldwork is typically fraught with vehicle problems, poor roads and bad weather. One thing you can always count on is that every expedition is exciting."
While a logical first step for modeling global warming is quantifying carbon flow, unresolved complexities surrounding the Arctic carbon cycle make it difficult to create models for that element.
Jacobson and his team take a complementary approach by analyzing naturally occurring isotopes of other elements, such as calcium and strontium, which track permafrost melting and therefore provide insight into carbon release.
Initial data show that rivers and permafrost have distinctly different calcium and strontium isotope compositions.When permafrost thaws during the summer and melts into rivers, the rivers show calcium and strontium isotope compositions that approach those for permafrost. Jacobson hypothesizes that in a warmer world, the permafrost signature in rivers will be more pronounced for longer periods of time.
Changes in the isotope composition of rivers can relate to changes in the release of carbon. So the calcium and strontium isotope composition of Arctic rivers can track the impact of warming on permafrost stability and carbon dioxide release.
"The ultimate goal is to establish a baseline to which future changes can be compared," Jacobson says. "Several years from now, we can compare real changes to model predictions and improve our understanding of how the system works."
http://www.nsf.gov
Monday, February 08, 2010
Soybean – The Interesting Legume
Soybean is an interesting plant. It provides a valuable protein source for human and animal consumption, it is an important feedstock for biodiesel production, and it interacts with soil-borne bacteria (Rhizobia) that capture atmospheric nitrogen and store it in the soil, a beneficial side-effect utilized during crop rotation. In an effort to unlock the full power of this plant, scientists have sequenced the soybean genome.“Most people are familiar with sequencing of the human genome,” begins Jeremy Schmutz, faculty scientist at Hudson Alpha Institute for Biotechnology, a partner laboratory with the DOE Joint Genome Institute (JGI). “The soybean genome was sequenced to provide scientists a better understanding of plant productivity, complex biochemical pathways, such as oil production, and pest and pathogen resistance just like the human genome is helping scientists to understand human diseases.”
The scientific team, led by Schmutz, used a process called “whole genome shotgun” to sequence the entire genome as a single effort. “With this technique, we were able to sequence and order the genome at one time so the scientific community could go directly from the genome sequence to breeding new varieties of soybean” said Schmutz.
At first glance, the soybean genome is an impressive size - 1,115 mega -base pairs (Mbp) (1,115,000 base pairs) – about 1/3 the size of the human genome, which contains approximately 3,000 Mbp. But by plant standards, the soybean genome is relatively small and tractable for genomics research.
The soybean genome, like other plant genomes, displays a feature called polyploidy. Schmutz explains, “During seed generation, whole regions of the genome can be duplicated. These duplications can infer a competitive advantage to the plant allowing it to thrive.”
Tuesday, February 02, 2010
Angry Flies are used in the Explain Human Aggression
Recently, biologist David Anderson set out to learn whether flies, like bees, can get angry--part of a broader effort to study how animal behavior relates to genetics."Every time you swat a fly away from your hamburger, it seems to come back to the food more aggressively or persistently," Anderson said. "People might wonder about whether there's such a thing as an 'angry' fly, but no one would challenge the idea of an angry bee--especially someone who's been stung by one."
To test his hypothesis, Anderson--who currently has two projects funded by the National Science Foundation (NSF) and who is a Howard Hughes Medical Institute (HHMI) Investigator at Caltech--created an experiment modeled after the traditional "bees-at-the-picnic-table" scenario using Drosophila, the common fruit fly (or more accurately, the vinegar fly).
"We developed the 'puff-o-mat' apparatus, with the idea of putting some fly food at one end, and then blowing the flies away from the food with a gentle puff of air every time they got close to it," he said. "Then we measured whether the flies became more agitated and approached the food more aggressively after experiencing this frustrating experience several times."As it turned out, they didn't even need the food.
"To our surprise," Anderson said, "simply blowing the flies off their feet several times in a row was sufficient to get them riled up. So we decided to focus on that--the agitation response--because it was much simpler to set up without the food, and without starving the flies. The part with the food never made it into the final paper," he added, referring to a study published in the journal Nature in early December, 2009.
The flies showed a primitive emotion-like behavior. Prompted by a series of brisk air puffs delivered in rapid succession, the flies ran around their test chambers in a frantic manner, and kept it up for several minutes. Even after the flies had calmed down, they remained hypersensitive to a single air puff.
The research showed that Drosophila produces a pheromone--a chemical messenger--that promotes aggression, and directly linked it to specific neurons in the fly's antenna. Anderson and his colleagues believe that the findings ultimately may be relevant to the relationship between the neurotransmitter dopamine and attention deficit hyperactivity disorder.
The brain of Drosophila contains about 20,000 neurons, and has long been considered a valuable system with which to study the genetic basis of learning, courtship, memory and circadian rhythms.
In recent years, Drosophila research has also been a powerful tool with which to study emotions. Most of the genes in the fruit fly are also in humans, including neurons that produce brain chemicals associated with several psychiatric disorders.
For example, in an earlier study, the researchers demonstrated how Drosophila hunkers down and stops moving in response to a steady wind--a sensory tool that could improve how the insects navigate during flight, and could help scientists learn more about the nervous system.
Anderson came to this field of research after amassing an impressive record studying the developmental biology of neural stem cells in mice. He decided he wanted to try something new. Switching scientific directions mid-career is always risky, it takes courage and a willingness to fail, but Anderson was game.
Resource http://www.nsf.gov/discoveries/
Sunday, January 31, 2010
Scientists dive to explore unique bacterial community
There’s not much in the ice-covered lakes in the McMurdo Dry Valleys to interest anglers looking to land the big one. But for scientists who want to know more about some of Earth’s earliest organisms — and, by extension, to recognize what life may look like on other planets — those unique ecosystems represent a useful portal to the past.
Indeed, the lack of fish or other animals high on the food chain has allowed the microorganisms that live within the lakes to flourish unmolested, developing into communities thick enough to accumulate in layers on the lake bottoms.
“The cool part is that you can see microbial ecosystems on a landscape scale. There aren’t too many places around the world where you can do that,” noted Dale Andersen, with the SETI Institute’s Carl Sagan Center for the Study of Life in the Universe and principal investigator on a project to learn more about the microorganisms that dwell in Lake Joyce.
Lake Joyce — one of about a dozen perennially ice-crusted lakes spread throughout the valleys — is all the more unique in that it is one of only two known lakes in the region where the microbes have produced microbialites. These carbonate structures, composed of the same minerals that make up a coral reef, grow right in the layers of cyanobacteria, called microbial mats.
Andersen explained that his team, funded by NASA’s Exobiology Program and supported in the field by the National Science Foundation (NSF), is interested in learning more about the conditions that allow these organisms to grow and flourish in their dark and cold ecosystem. In turn, that information should shed light on the behavior of similar organisms billions of years ago.
“There are only a few places in the world where you can go to find living examples of those earlier ecosystems,” Andersen stressed. “The lakes in the Dry Valleys actually provide a very nice window back in time to compare notes, so to speak, with the fossil record.”
Andersen has made two previous trips to Lake Joyce, where he first discovered the carbonate structures growing from the microbial mat communities at about 20 meters depth. This will be the first extended study of the carbonate structures in a Dry Valleys lake, he said.
“The initial observations that we have are that the structures are pretty cool and there’s lots going on, but we don’t know much about them,” Andersen said.
“Each lake is totally different,” he added. “The external factors seem to be pushing the communities in different directions. That’s part of what makes these very unique ecosystems interesting to study — they’re essentially right next to one another and they’re each so very distinctive.”
Indeed, the lack of fish or other animals high on the food chain has allowed the microorganisms that live within the lakes to flourish unmolested, developing into communities thick enough to accumulate in layers on the lake bottoms.
“The cool part is that you can see microbial ecosystems on a landscape scale. There aren’t too many places around the world where you can do that,” noted Dale Andersen, with the SETI Institute’s Carl Sagan Center for the Study of Life in the Universe and principal investigator on a project to learn more about the microorganisms that dwell in Lake Joyce.
Lake Joyce — one of about a dozen perennially ice-crusted lakes spread throughout the valleys — is all the more unique in that it is one of only two known lakes in the region where the microbes have produced microbialites. These carbonate structures, composed of the same minerals that make up a coral reef, grow right in the layers of cyanobacteria, called microbial mats.
Andersen explained that his team, funded by NASA’s Exobiology Program and supported in the field by the National Science Foundation (NSF), is interested in learning more about the conditions that allow these organisms to grow and flourish in their dark and cold ecosystem. In turn, that information should shed light on the behavior of similar organisms billions of years ago.
“There are only a few places in the world where you can go to find living examples of those earlier ecosystems,” Andersen stressed. “The lakes in the Dry Valleys actually provide a very nice window back in time to compare notes, so to speak, with the fossil record.”
Andersen has made two previous trips to Lake Joyce, where he first discovered the carbonate structures growing from the microbial mat communities at about 20 meters depth. This will be the first extended study of the carbonate structures in a Dry Valleys lake, he said.
“The initial observations that we have are that the structures are pretty cool and there’s lots going on, but we don’t know much about them,” Andersen said.
“Each lake is totally different,” he added. “The external factors seem to be pushing the communities in different directions. That’s part of what makes these very unique ecosystems interesting to study — they’re essentially right next to one another and they’re each so very distinctive.”
Thursday, January 28, 2010
New wind farm in Antarctica to help power U.S., New Zealand research stations
Electrical power generation has gotten a different spin for two Antarctic research bases. U.S. and New Zealand officials held an opening ceremony on Jan. 16 for a three-turbine wind farm recently built on Ross Island. U.S. Ambassador David Huebner and New Zealand Foreign Minister Murray McCully officiated by video link with the site from New Zealand’s northern city of Auckland.
Live from Antarctica!
Check out the Antarctica New Zealand Wind Farm Web camera for a near real-time look at the turbines and the nearby sea ice.U.S. Secretary of State Hillary Clinton was also scheduled to attend the ceremony in Auckland, but was called away to help deal with the earthquake crisis in Haiti.
The wind farm will help power both McMurdo Station, the main research base for the U.S. Antarctic Program (USAP), and Antarctica New Zealand’s Scott Base. The two facilities, which support a range of polar research, are only about 2 miles apart and share logistical operations.
Each wind turbine can generate up to 330 kilowatts on a site called Crater Hill between McMurdo Station and Scott Base. Engineers estimate the wind farm will cut fuel consumption by about 240,000 gallons every year.
Wind-generated electricity will account for up to 15 percent of McMurdo Station’s annual electricity demand, but nearly all of Scott Base’s. Currently, both stations draw all of their electrical and heat demand from diesel generators and diesel-fired boilers.
Officials from the National Science Foundation, which manages the USAP, were expected to hold a separate ceremony to commemorate the green achievement on Jan. 20. NSF Director Arden Bement and NSF Office of Polar Programs Director Karl Erb were both to be in attendnace. Bement and Erb also attended a plaque dedication on the site of a former nuclear power plant that was shut down about 40 years ago — the one and only such facility built and operated in Antarctica.
Total cost of the wind turbine project was about $7.4 million, with New Zealand covering most of the cost as part of its contribution to the two countries’ shared logistics pool.USAP personnel upgraded roads and transported equipment to Crater Hill, as well as conducted site surveys and provided various supplies and equipment, to support the construction.If deemed successful, the wind farm may be expanded in other areas around Ross Island to further reduce McMurdo Station’s reliance on fossil fuels.
Live from Antarctica!
Check out the Antarctica New Zealand Wind Farm Web camera for a near real-time look at the turbines and the nearby sea ice.U.S. Secretary of State Hillary Clinton was also scheduled to attend the ceremony in Auckland, but was called away to help deal with the earthquake crisis in Haiti.
The wind farm will help power both McMurdo Station, the main research base for the U.S. Antarctic Program (USAP), and Antarctica New Zealand’s Scott Base. The two facilities, which support a range of polar research, are only about 2 miles apart and share logistical operations.
Each wind turbine can generate up to 330 kilowatts on a site called Crater Hill between McMurdo Station and Scott Base. Engineers estimate the wind farm will cut fuel consumption by about 240,000 gallons every year.
Wind-generated electricity will account for up to 15 percent of McMurdo Station’s annual electricity demand, but nearly all of Scott Base’s. Currently, both stations draw all of their electrical and heat demand from diesel generators and diesel-fired boilers.
Officials from the National Science Foundation, which manages the USAP, were expected to hold a separate ceremony to commemorate the green achievement on Jan. 20. NSF Director Arden Bement and NSF Office of Polar Programs Director Karl Erb were both to be in attendnace. Bement and Erb also attended a plaque dedication on the site of a former nuclear power plant that was shut down about 40 years ago — the one and only such facility built and operated in Antarctica.
Total cost of the wind turbine project was about $7.4 million, with New Zealand covering most of the cost as part of its contribution to the two countries’ shared logistics pool.USAP personnel upgraded roads and transported equipment to Crater Hill, as well as conducted site surveys and provided various supplies and equipment, to support the construction.If deemed successful, the wind farm may be expanded in other areas around Ross Island to further reduce McMurdo Station’s reliance on fossil fuels.
Thursday, January 21, 2010
Bugs: Victims of Climate Change
If it were up to Jessica Hellmann, insects such as butterflies and beetles would wield just as much conservation clout as traditional conservation icons, such as polar bears, tigers and dolphins.Why?
"Animals such as polar bears, tigers and dolphins are tremendously important, but mostly because they help define how we think about our relationship with the natural world," says Hellmann. "But when it comes to the functioning of ecosystems, insects are where it's at."
Why are insects so ecologically important? "They carry diseases, they pollinate and they have economic impacts on crops and timber," says Hellmann, a biologist at the University of Notre Dame. In fact, almost 80 percent of the world's crop plants require pollination, and the annual value of insect-pollinated crops in the U.S. is about $20 billion. What's more, most of the multicellular living organisms on Earth are insects.
They are also particularly sensitive to climate change--as invertebrates, they can't regulate their own body temperatures--making them "great little thermometers," Hellmann adds.
On the road again
How will those "great little thermometers" respond when climate change makes their habitats too hot or too dry for them?
Research conducted by Hellmann and Shannon Pelini, one of Hellmann's doctoral students, indicates that global warming may affect a single insect species differently throughout its various life stages, and that global warming affects different insect species in different ways.
Most importantly, as climate change progresses, some insects may become trapped--like fish out of water--in habitats that can no longer support them. The insects may therefore go extinct or lose genetically important segments of their populations. But other species, and no one knows which ones yet, may be able to reach cooler climates by moving north on their own.
Will such mobile species be able to survive on the unfamiliar plants living in their new habitats? To help answer that question, Pelini conducted laboratory experiments that involve exposing caterpillars of two butterfly species to climates and plants that occur across their ranges, and then monitoring the growth and survival rates of these groups.
She will soon announce in the journal Proceedings of the National Academy of Sciences (PNAS) how populations of these two butterfly species that live at the edges of their ranges will be affected by climate change and the various factors that may limit or reduce their northward expansion.
Hellmann is currently following up on Pelini's research by surveying thousands of genes in the two butterfly species in order to identify the genes that are turned off or on by climate change. These studies are designed to reveal the genetic bases for the tolerance of some insect species to climate change and the intolerance of others.
Tuesday, January 19, 2010
Real hero: Farley Mowat
Born: 1921 Belleville, Ontario Canada
Why he’s an Environmental Star! While living in Saskatchewan, young Farley visited the Arctic and started his lifelong passion for the preservation of Canada’s wildlife. Farley is one of Canada’s most famous conservationists and storytellers.
Schooling: University of Toronto
Facts and Figures: Farley’s books have sold over 18 million copies worldwide in 24 languages. Owls in the Family is perhaps Farley’s most famous book. A story that many Canadians have read in school, it is a popular tale about a young boy, his pets and their adventures together and a great read!
Did you know?
Farley is the great-grand-nephew of Ontario premier Sir Oliver Mowat
At the age of 13, Mowat founded a nature newsletter called Nature Lore.
Most awesome thing about Farley Mowat:
He was inspired to write the 1963 book Never Cry Wolf after spending time living in the Arctic observing the lives of wolves. At the time people were concerned with the declining caribou populations and suspected that the wolves were eating the caribou. They decided that the best way to protect the caribou would be to kill some of the wolves. After months of observation Farley concluded that the opposite was true! The wolves actually strengthened the caribou tribe because the wolves mainly ate field mice and only ate old or sick caribou — killing off the weakest. Farley concluded that the hunters in the area were using the wolves as scapegoats for the decline of the caribous, when in fact they were the ones hunting and killing them.
Why he’s an Environmental Star! While living in Saskatchewan, young Farley visited the Arctic and started his lifelong passion for the preservation of Canada’s wildlife. Farley is one of Canada’s most famous conservationists and storytellers.
Schooling: University of Toronto
Facts and Figures: Farley’s books have sold over 18 million copies worldwide in 24 languages. Owls in the Family is perhaps Farley’s most famous book. A story that many Canadians have read in school, it is a popular tale about a young boy, his pets and their adventures together and a great read!
Did you know?
Farley is the great-grand-nephew of Ontario premier Sir Oliver Mowat
At the age of 13, Mowat founded a nature newsletter called Nature Lore.
Most awesome thing about Farley Mowat:
He was inspired to write the 1963 book Never Cry Wolf after spending time living in the Arctic observing the lives of wolves. At the time people were concerned with the declining caribou populations and suspected that the wolves were eating the caribou. They decided that the best way to protect the caribou would be to kill some of the wolves. After months of observation Farley concluded that the opposite was true! The wolves actually strengthened the caribou tribe because the wolves mainly ate field mice and only ate old or sick caribou — killing off the weakest. Farley concluded that the hunters in the area were using the wolves as scapegoats for the decline of the caribous, when in fact they were the ones hunting and killing them.
Monday, January 18, 2010
About Deep Space Communications
One of the most important and predominant functions involved in the exploration of space is its communication system. This system is responsible for sending scientific data from spacecraft back to Earth. It also provides the capability of tracking the spacecraft and commanding it to take certain actions. Without an effective communications system a successful mission would not be possible.
The challenge of deep space communication has been the enormous range of distances that spacecraft have traveled in the past 50 years. Planetary spacecraft have reached distant planets tens of billions of miles from Earth, and have successfully performed their functions. The necessity of minimizing spacecraft mass presents a major challenge to communications system engineers, as engineers must consider the issues of providing power supply, antennae, and many other necessary devices and supporting elements for a communications system. Another important challenge is the extreme reliability required of the communications systems on the spacecraft. Once the spacecraft is launched, on-board failures can be repaired only by relying upon redundant and adaptive systems. Communication engineers must take into consideration such factors as system degradation, aging, and imperfect antenna positioning, as well as operations and data procedures.
In the past, spacecraft data return rates have been tens to hundreds of kilobits per second (kbps) and uplink command data rates have been limited to a few kbps. Recent missions such as MRO can transmit data to Earth at rates as high as 6 megabits per second. For more demanding missions in the near future, much higher data capabilities will be required.
DSN image
The Deep Space Network (DSN) operated for NASA by the Jet Propulsion Laboratory (JPL), provides deep space communications, tracking of spacecraft, and performs many scientific experiments. Because future space missions promise to explore the far reaches of the solar system and beyond, the DSN would need to expand its technological and communications capabilities to meet greater science data return rates and the requirements of advanced spacecraft. For example, by one estimate, the DSN might have to support over twice the missions in 2020 as it supported in 2005, and the data rate from each mission could average at least a factor of 10 higher.
The DSN consists of antenna arrays in 3 locations around the world; near Madrid, Spain; near Canberra, Australia; the Goldstone facility in California’s Mojave Desert, and the command center at JPL in California. These facilities, approximately 120 degrees apart on Earth, provide constant coverage for a mission at critical times. Each facility has a number of antennae some of which can be operated as an array, including at least two 34-meter arrays, and a giant 70-meter array in each location. Use of the arrays is scheduled well in advance for all interplanetary missions as their use is in high demand.
To enable future critical space exploration missions, new technology investments are needed so that future programs will continue to be successful and affordable (i.e. no specific program can afford to bear the burden of the technology development by itself). JPL sponsors internal development of several deep space communications efforts.
The challenge of deep space communication has been the enormous range of distances that spacecraft have traveled in the past 50 years. Planetary spacecraft have reached distant planets tens of billions of miles from Earth, and have successfully performed their functions. The necessity of minimizing spacecraft mass presents a major challenge to communications system engineers, as engineers must consider the issues of providing power supply, antennae, and many other necessary devices and supporting elements for a communications system. Another important challenge is the extreme reliability required of the communications systems on the spacecraft. Once the spacecraft is launched, on-board failures can be repaired only by relying upon redundant and adaptive systems. Communication engineers must take into consideration such factors as system degradation, aging, and imperfect antenna positioning, as well as operations and data procedures.
In the past, spacecraft data return rates have been tens to hundreds of kilobits per second (kbps) and uplink command data rates have been limited to a few kbps. Recent missions such as MRO can transmit data to Earth at rates as high as 6 megabits per second. For more demanding missions in the near future, much higher data capabilities will be required.
DSN image
The Deep Space Network (DSN) operated for NASA by the Jet Propulsion Laboratory (JPL), provides deep space communications, tracking of spacecraft, and performs many scientific experiments. Because future space missions promise to explore the far reaches of the solar system and beyond, the DSN would need to expand its technological and communications capabilities to meet greater science data return rates and the requirements of advanced spacecraft. For example, by one estimate, the DSN might have to support over twice the missions in 2020 as it supported in 2005, and the data rate from each mission could average at least a factor of 10 higher.
The DSN consists of antenna arrays in 3 locations around the world; near Madrid, Spain; near Canberra, Australia; the Goldstone facility in California’s Mojave Desert, and the command center at JPL in California. These facilities, approximately 120 degrees apart on Earth, provide constant coverage for a mission at critical times. Each facility has a number of antennae some of which can be operated as an array, including at least two 34-meter arrays, and a giant 70-meter array in each location. Use of the arrays is scheduled well in advance for all interplanetary missions as their use is in high demand.
To enable future critical space exploration missions, new technology investments are needed so that future programs will continue to be successful and affordable (i.e. no specific program can afford to bear the burden of the technology development by itself). JPL sponsors internal development of several deep space communications efforts.
Sunday, January 10, 2010
Ozone hole drive rapid changes
One finding from recent years that received prominence in the SCAR report concerned the effects of the ozone hole on the Antarctic climate.Unlike the coastal areas, particularly in West Antarctica, the interior of Antarctica has cooled slightly, according to polar researchers cited in the SCAR report. That’s because the ozone hole over the Southern Hemisphere has cooled the stratosphere, the layer of the atmosphere above the troposphere that people inhabit.
However, the ocean around the continent and regions to the north are warming. The temperature differential has caused atmospheric circulation to intensify around Antarctica, effectively shielding much of the continent from the intrusion of warmer air to the north.
But as the ozone hole heals, those westerly winds will ease, allowing warmer air to mix more easily into the Antarctic atmosphere. The SCAR report estimates a continent-wide temperature increase of 3 degrees Celsius by 2100.
“This is what has happened in the northern hemisphere. You have a relatively warm Arctic and a warm low- to mid-latitudes, and the westerlies have slowed down,” Mayewski said. “The big questions for the Antarctic are when it will happen and how fast will it happen.”
Mayewski said based on climate records, particularly from ice cores, that sudden shifts in position and strength of the westerlies have created many of the abrupt climate changes of the past.
Mayewski said: “The implicit but not explicit statement in my mind in this report is the fact that we could very well be headed for not a linear change in the westerlies, but an abrupt change in the westerlies,” he said. “If we experience a very abrupt weakening of the westerlies — we can show that it happened in the past — we could very well have accelerated levels of warming in Antarctica.”
A recent paper in the journal Geophysical Research Letters by Marco Tedesco at City College of New York and Andrew Monaghan at the National Center for Atmospheric Research in Boulder, Colo., suggested that a 30-year record low in Antarctic snowmelt during the 2008-09 austral summer was likely due to intensified westerlies and El Niño-Southern Oscillation (ENSO). ENSO is a periodic change in oceanic and atmospheric conditions in the tropical Pacific Ocean that has far-reaching effects on weather around the world.
Source: http://antarcticsun.usap.gov/science/
Thursday, January 07, 2010
Researchers find similarities between Earth and Saturn's largest moon
Researchers using ground-based telescopes and space probes make amazing discoveries about the atmospheric cycle of Saturn’s largest moon, and find similarities to Earth. Our knowledge of Titan has improved considerably over the last five years. Before that, Saturn's largest satellite had only been hastily approached by a handful of space probes.
In 1980, the Voyager-1 spacecraft took advantage of a flyby to take a few mysterious, yet frustrating, close-ups of Titan's opaque, rusty atmosphere. Despite its color, Titan actually seemed to look a lot like the early Earth.
There was a general feeling of excitement and perplexity: what lay beneath this atmosphere? Could Titan support life? In July 2004, NASA's Cassini space probe entered Saturn's distant realm, this time to stay. The probe was designed right after Voyager's visit by a scientific community eager to unveil those new mysteries.
And unveil them it did. It has been hard to keep up with the flow of discoveries delivered from Titan to Earth since then. We now know that the 5,150-kilometer- (km, or 3,200-mile-) wide world has lakes and riverbeds. Earlier this year, even fog was discovered at Titan's South Pole.
Even more compelling is the fact that, just like similar features on Earth, all of those features are tightly related. Evaporated liquids create clouds that are carried around the planet by winds--and probably cause precipitation. This has never been seen on any other extraterrestrial body.
Moreover, Titan's atmospheric cycle is not a water cycle. It is instead an exotic climate of hydrocarbons that features methane and ethane. On Earth, those are gases, but the extremely cold temperature of Titan, around minus 290 degrees Fahrenheit (F, or minus 180 degrees Celcius), allows them to be liquid as well (and maybe even solid).
In 1980, the Voyager-1 spacecraft took advantage of a flyby to take a few mysterious, yet frustrating, close-ups of Titan's opaque, rusty atmosphere. Despite its color, Titan actually seemed to look a lot like the early Earth.
There was a general feeling of excitement and perplexity: what lay beneath this atmosphere? Could Titan support life? In July 2004, NASA's Cassini space probe entered Saturn's distant realm, this time to stay. The probe was designed right after Voyager's visit by a scientific community eager to unveil those new mysteries.
And unveil them it did. It has been hard to keep up with the flow of discoveries delivered from Titan to Earth since then. We now know that the 5,150-kilometer- (km, or 3,200-mile-) wide world has lakes and riverbeds. Earlier this year, even fog was discovered at Titan's South Pole.
Even more compelling is the fact that, just like similar features on Earth, all of those features are tightly related. Evaporated liquids create clouds that are carried around the planet by winds--and probably cause precipitation. This has never been seen on any other extraterrestrial body.
Moreover, Titan's atmospheric cycle is not a water cycle. It is instead an exotic climate of hydrocarbons that features methane and ethane. On Earth, those are gases, but the extremely cold temperature of Titan, around minus 290 degrees Fahrenheit (F, or minus 180 degrees Celcius), allows them to be liquid as well (and maybe even solid).
Resource: http://www.nsf.gov/discoveries/
Tuesday, January 05, 2010
Green algae helps in Advancing Bio-hydrogen
Photosynthetic organisms offer a biological paradigm for the conversion of light energy into chemical forms. Some of these organisms are capable of transducing this energy directly into H2. The green alga Chlamydomonas reinhardtii is an example of one such organism that could play a major role in future commercial H2-production system. However, the complexity of the metabolism linked to H2-production pathways in this organism demands the development of a computational model by which to integrate and understand disparate observations over various mutations and environmental conditions.
The grand scientific challenge of creating a complete, in silico simulation of a living cell still faces daunting obstacles. Biomolecular science has proceeded by studying prototypical systems, with the understanding that the knowledge gained is transferable to other systems to some extent. However, for quantitative modeling of a single system, complete knowledge must be available for that particular system to achieve consistency—assuming transferability of knowledge from prototypical systems may lead to fundamental errors in model interpretation.
This project will exploit existing and newly generated knowledge to construct an in silico simulation of metabolism relating to H2 production in C. reinhardtii. It will provide a fundamental understanding of essential metabolic pathways in photosynthetic green algae and enable rational engineering and optimization of those pathways. It will also serve a broader community by providing information critical to understanding other hydrogen metabolizing and fermentative organisms of interest in renewable energy research.
The Department of Energy's mission is to advance the national, economic and energy security of the United States. Within the Genomics:GTL program, systems biology has been identified as playing a key role in meeting the Department’s mission. Furthermore, the “hydrogen economy” has been established as an important component in a multi-faceted strategy for energy independence and renewability.
The grand scientific challenge of creating a complete, in silico simulation of a living cell still faces daunting obstacles. Biomolecular science has proceeded by studying prototypical systems, with the understanding that the knowledge gained is transferable to other systems to some extent. However, for quantitative modeling of a single system, complete knowledge must be available for that particular system to achieve consistency—assuming transferability of knowledge from prototypical systems may lead to fundamental errors in model interpretation.
This project will exploit existing and newly generated knowledge to construct an in silico simulation of metabolism relating to H2 production in C. reinhardtii. It will provide a fundamental understanding of essential metabolic pathways in photosynthetic green algae and enable rational engineering and optimization of those pathways. It will also serve a broader community by providing information critical to understanding other hydrogen metabolizing and fermentative organisms of interest in renewable energy research.
The Department of Energy's mission is to advance the national, economic and energy security of the United States. Within the Genomics:GTL program, systems biology has been identified as playing a key role in meeting the Department’s mission. Furthermore, the “hydrogen economy” has been established as an important component in a multi-faceted strategy for energy independence and renewability.
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