9:55 PM
Gabriella Brianna
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Cassini radar sees sand dunes on Saturn's giant moon Titan (upper photo) that are sculpted like Namibian sand dunes on Earth (lower photo). The bright features in the upper radar photo are not clouds but topographic features among the dunes. Image credit: NASA/JPL (upper photo); NASA/JSC (lower photo) - Larger image
The answer to the mystery of dune patterns on Saturn's moon Titan did turn out to be blowing in the wind. It just wasn't from the direction many scientists expected.
Basic principles describing the rotation of planetary atmospheres and data from the European Space Agency's Huygens probe led to circulation models that showed surface winds streaming generally east-to-west around Titan's equatorial belt. But when NASA's Cassini spacecraft obtained the first images of dunes on Titan in 2005, the dunes' orientation suggested the sands – and therefore the winds – were moving from the opposite direction, or west to east.
A new paper by Tetsuya Tokano in press with the journal Aeolian Research seeks to explain the paradox. It explains that seasonal changes appear to reverse wind patterns on Titan for a short period. These gusts, which occur intermittently for perhaps two years, sweep west to east and are so strong they do a better job of transporting sand than the usual east-to-west surface winds. Those east-to-west winds do not appear to gather enough strength to move significant amounts of sand.
A related perspective article about Tokano's work by Cassini radar scientist Ralph Lorenz, the lead author on a 2009 paper mapping the dunes, appears in this week's issue of the journal Science.
"It was hard to believe that there would be permanent west-to-east winds, as suggested by the dune appearance," said Tokano, of the University of Cologne, Germany. "The dramatic, monsoon-type wind reversal around equinox turns out to be the key."
The dunes track across the vast sand seas of Titan only in latitudes within 30 degrees of the equator. They are about a kilometer (half a mile) wide and tens to hundreds of kilometers (miles) long. They can rise more than 100 meters (300 feet) high. The sands that make up the dunes appear to be made of organic, hydrocarbon particles. The dunes' ridges generally run west-to-east, as wind here generally sheds sand along lines parallel to the equator.
Scientists predicted winds in the low latitudes around Titan's equator would blow east-to-west because at higher latitudes the average wind blows west-to-east. The wind forces should balance out, based on basic principles of rotating atmospheres.
Tokano re-analyzed a computer-based global circulation model for Titan he put together in 2008. That model, like others for Titan, was adapted from ones developed for Earth and Mars. Tokano added in new data on Titan topography and shape based on Cassini radar and gravity data. In his new analysis, Tokano also looked more closely at variations in the wind at different points in time rather than the averages. Equinox periods jumped out.
Equinoxes occur twice a Titan year, which is about 29 Earth years. During equinox, the sun shines directly over the equator, and heat from the sun creates upwelling in the atmosphere. The turbulent mixing causes the winds to reverse and accelerate. On Earth, this rare kind of wind reversal happens over the Indian Ocean in transitional seasons between monsoons.
The episodic reverse winds on Titan appear to blow around 1 to 1.8 meters per second (2 to 4 mph). The threshold for sand movement appears to be about 1 meter per second (2 mph), a speed that the typical east-to-west winds never appear to surpass. Dune patterns sculpted by strong, short episodes of wind can be found on Earth in the northern Namib sand seas in Namibia, Africa.
"This is a subtle discovery -- only by delving into the statistics of the winds in the model could this rather distressing paradox be resolved," said Ralph Lorenz, a Cassini radar scientist based at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. "This work is also reassuring for preparations for proposed future missions to Titan, in that we can become more confident in predicting the winds which can affect the delivery accuracy of landers, or the drift of balloons."
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL manages the Cassini-Huygens mission for NASA's Science Mission Directorate. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. JPL is a division of the California Institute of Technology in Pasadena.
For more information visit http://www.jpl.nasa.gov/news/news.cfm?release=2010-251
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9:34 PM
Gabriella Brianna
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This is the first dust devil that NASA's Mars Exploration Rover Opportunity has observed in the rover's six-and-a-half years on Mars. Image Credit: NASA/JPL-Caltech/Cornell University/Texas A&M - Larger image
In its six-and-a-half years on Mars, NASA's Mars Exploration Rover Opportunity had never seen a dust devil before this month, despite some systematic searches in past years and the fact that its twin rover, Spirit, has seen dozens of dust devils at its location halfway around the planet.
A tall column of swirling dust appears in a routine image that Opportunity took with its panoramic camera on July 15. The rover took the image in the drive direction, east-southeastward, right after a drive of about 70 meters (230 feet). The image was taken for use in planning the next drive.
"This is the first dust devil seen by Opportunity," said Mark Lemmon of Texas A&M University, College Station, a member of the rover science team.
Spirit's area, inside Gusev Crater, is rougher in ground texture, and dustier, than the area where Opportunity is working in the Meridiani Planum region. Those factors at Gusev allow vortices of wind to form more readily and raise more dust, compared to conditions at Meridiani, Lemmon explained. Orbiters have photographed tracks left by dust devils near Opportunity, but the tracks are scarcer there than near Spirit. Swirling winds at Meridiani may be more common than visible signs of them, if the winds occur where there is no loose dust to disturb.
Just one day before Opportunity captured the dust devil image, wind cleaned some of the dust off the rover's solar array, increasing electricity output from the array by more than 10 percent.
"That might have just been a coincidence, but there could be a connection," Lemmon said. The team is resuming systematic checks for afternoon dust devils with Opportunity's navigation camera, for the first time in about three years.
Opportunity and Spirit arrived on Mars in January 2004 for missions designed to last for three months. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover Project for the NASA Science Mission Directorate, Washington. For more information about the project and images from the rovers.
For more information visit http://www.jpl.nasa.gov/news/news.cfm?release=2010-250
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9:27 PM
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NASA’s Desert Research and Technology Studies (RATS) project is a NASA-led team of engineers, researchers and scientists. The 2010 Desert RATS field tests will be conducted in the Arizona desert, an analog location used to simulate future planetary exploration missions.
The annual Desert RATS project brings together a variety of science and advanced engineering disciplines into a coordinated field test in terrain conditions analogous to other planets or the moon. The purpose of Desert RATS is to assess new and novel concepts for surface exploration, including astronaut activities, crew rovers, robots and mission control.
For more information visit http://www.nasa.gov/exploration/analogs/desert_rats.html
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8:59 PM
Gabriella Brianna
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The members of the International Space Station’s Expedition 24 crew shifted their sleep schedule Monday in preparation for their mission’s first spacewalk, waking up at about 2:40 p.m. EDT.
Flight Engineers Fyodor Yurchikhin, a veteran of three spacewalks in 2007 during Expedition 15, and Mikhail Kornienko, a spacewalk rookie, will perform the six-hour spacewalk. The pair will exit the Pirs docking compartment and work outside the Zarya and Zvezda modules. The Pirs Docking Compartment hatch is slated to open at 11:45 p.m. to begin the excursion.
The pair will outfit the Rassvet module’s Kurs automated rendezvous system, install cables and remove and replace a video camera. Kurs is a Russian radio telemetry system that allows automated dockings of unmanned spacecraft such as the Progress resupply vehicle. The new video camera will document the rendezvous and docking of future Automated Transfer Vehicles to the aft end of the Zvezda service module.
The next spacewalk will take place Aug. 5 with Flight Engineers Tracy Caldwell Dyson and Doug Wheelock. The astronauts will exit the Quest airlock and install a Portable Data Grapple Fixture (PDGF) on the Zarya module extending the reach of Canadarm2, the station’s robotic arm, and increasing a spacewalker’s capabilities. They also will jettison old multi-layer insulation removed for the PDGF install and mate power connectors to Zarya.
Flight controllers will decide Tuesday whether or not to proceed with the robotic work by the Dextre Special Purpose Dexterous Manipulator to replace a failed Remote Power Control Module, or RPCM, on the station’s P1 truss. The RPCM replacement was slated for July 21, but during a test extraction procedure on July 20, ground teams determined that the force needed to remove the RPCM was higher than demonstrated with ground testing. The team is working towards the next attempt of the test extraction on Wednesday and the full replacement procedure Thursday of this week pending Tuesday’s review.
For More information visit http://www.nasa.gov/mission_pages/station/main/index.html
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9:15 PM
Gabriella Brianna
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A team recovers the hybrid robotic vehicle Nereus aboard the research vessel Cape Hatteras during a partially NASA-funded expedition to the Mid-Cayman Rise in October 2009. A search for new hydrothermal vent sites along the 110-kilometer-long ridge, the expedition featured the first use of Nereus in "autonomous," or free-swimming, mode. Image credit: Woods Hole Oceanographic Institution - Larger view An expedition partially funded by NASA, part of a program to search extreme environments for geological, biological and chemical clues to the origins and evolution of life, has discovered the deepest known hydrothermal vent in the world, nearly 5,000 meters (16,400 feet) below the surface of the western Caribbean Sea. The research will help extend our understanding of the limits to which life can exist on Earth and help prepare for future efforts to search for life on other planets.
An interdisciplinary team led by Woods Hole Oceanographic Institution, Woods Hole, Mass., and including research scientist Max Coleman of NASA's Jet Propulsion Laboratory, Pasadena, Calif., sailed to the western Caribbean in October 2009 aboard the research vessel Cape Hatteras. Using sensors mounted on equipment and robotic vehicles, they searched for deep-sea hydrothermal vents along the 110-kilometer-long (68-mile-long) Mid-Cayman Rise, an ultra-slow spreading ridge located in the Cayman Trough -- the deepest point in the Caribbean Sea. Results of their research are published this week in the Proceedings of the National Academy of Sciences.
While high-temperature submarine vents were first discovered more than 30 years ago, the majority of the global Mid-Ocean Ridge, an underwater mountain range that snakes its way for more than 56,000 kilometers (35,000 miles) between Earth's continents, remains unexplored for hydrothermal activity. While such activity occurs on spreading centers all around the world, scientists are particularly interested in Earth's ultra-slow spreading ridges, like the Mid-Cayman Rise, which may host systems that are particularly relevant to pre-biotic chemistry and the origins of life. The Mid-Cayman Rise is part of the tectonic boundary between the North American and Caribbean Plates. At the boundary where the plates are being pulled apart, new material wells up from Earth's interior to form new crust on the seafloor.
The researchers found that the Mid-Cayman Rise hosts at least three discrete hydrothermal sites, each representing a different type of water-rock interaction. The diversity of the newly discovered vent types, their geologic settings and their relative geographic isolation make the Mid-Cayman Rise a unique environment in the world's ocean.
"This was probably the highest-risk expedition I have ever undertaken," said chief scientist Chris German, a Woods Hole Oceanographic Institution geochemist who has pioneered the use of autonomous underwater vehicles to search for hydrothermal vent sites. "We know hydrothermal vents appear along ridges approximately every 100 kilometers [62 miles]. But this ridge crest is only 100 kilometers long, so we should only have expected to find evidence for one site at most. So finding evidence for three sites was quite unexpected - but then finding out that our data indicated that each site represents a different style of venting - one of every kind known, all in pretty much the same place - was extraordinarily cool."
The team identified the deepest known hydrothermal vent site and two additional distinct types of vents, one of which is believed to be a shallow, low-temperature vent of a kind that has been reported only once previously - at the "Lost City" site in the mid-Atlantic Ocean.
"Being the deepest, these hydrothermal vents support communities of organisms that are the furthest from the ocean surface and sources of energy like sunlight," said JPL co-author Coleman. "Most life on Earth is sustained by food chains that begin with sunlight as their energy source. That's not an option for possible life deep in the ocean of Jupiter's icy moon Europa, prioritized by NASA for future exploration. However, organisms around the deep vents get energy from the chemicals in hydrothermal fluid, a scenario we think is similar to the seafloor of Europa, and this work will help us understand what we might find when we search for life there."
"We were particularly excited to find compelling evidence for high-temperature venting at almost 5,000 meters depth," said Julie Huber, a scientist in the Josephine Bay Paul Center at the Marine Biological Laboratory in Woods Hole. "We have absolutely zero microbial data from high-temperature vents at this depth." Huber and Marine Biological Laboratory postdoctoral scientist Julie Smith participated in this cruise to collect samples, and all of the microbiology work for this paper was carried out in Huber's laboratory. "With the combination of extreme pressure, temperature and chemistry, we are sure to discover novel microbes in this environment," Huber added. "We look forward to returning to the Cayman and sampling these vents in the near future. We are sure to expand the known growth parameters and limits for life on our planet by exploring these new sites."
For more information visit http://www.jpl.nasa.gov/news/news.cfm?release=2010-242
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10:33 PM
Gabriella Brianna
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Valles Marineris, the "Grand Canyon of Mars," sprawls wide enough to reach from Los Angeles to nearly New York City, if it were located on Earth. The red outline box shows the location of a second, full-resolution image. Credit: NASA/JPL/Arizona State University - Larger image
A camera aboard NASA's Mars Odyssey spacecraft has helped develop the most accurate global Martian map ever. Researchers and the public can access the map via several websites and explore and survey the entire surface of the Red Planet.
The map was constructed using nearly 21,000 images from the Thermal Emission Imaging System, or THEMIS, a multi-band infrared camera on Odyssey. Researchers at Arizona State University's Mars Space Flight Facility in Tempe, in collaboration with NASA's Jet Propulsion Laboratory in Pasadena, Calif., have been compiling the map since THEMIS observations began eight years ago.
The pictures have been smoothed, matched, blended and cartographically controlled to make a giant mosaic. Users can pan around images and zoom into them. At full zoom, the smallest surface details are 100 meters (330 feet) wide. While portions of Mars have been mapped at higher resolution, this map provides the most accurate view so far of the entire planet.
The new map is available at: http://www.mars.asu.edu/maps/?layer=thm_dayir_100m_v11 .
Advanced users with large bandwidth, powerful computers and software capable of handling images in the gigabyte range can download the full-resolution map in sections at: http://www.mars.asu.edu/data/thm_dir_100m .
"We've tied the images to the cartographic control grid provided by the U.S. Geological Survey, which also modeled the THEMIS camera's optics," said Philip Christensen, principal investigator for THEMIS and director of the Mars Space Flight Facility. "This approach lets us remove all instrument distortion, so features on the ground are correctly located to within a few pixels and provide the best global map of Mars to date."
Working with THEMIS images from the new map, the public can contribute to Mars exploration by aligning the images to within a pixel's accuracy at NASA's "Be a Martian" website, which was developed in cooperation with Microsoft Corp. Users can visit the site at: http://beamartian.jpl.nasa.gov/maproom#/MapMars .
"The Mars Odyssey THEMIS team has assembled a spectacular product that will be the base map for Mars researchers for many years to come," said Jeffrey Plaut, Odyssey project scientist at JPL. "The map lays the framework for global studies of properties such as the mineral composition and physical nature of the surface materials."
Other sites build upon the base map. At Mars Image Explorer, which includes images from every Mars orbital mission since the mid-1970s, users can search for images using a map of Mars at: http://themis.asu.edu/maps .
"The broad purpose underlying all these sites is to make Mars exploration easy and engaging for everyone," Christensen said. "We are trying to create a user-friendly interface between the public and NASA's Planetary Data System, which does a terrific job of collecting, validating and archiving data."
Mars Odyssey was launched in April 2001 and reached the Red Planet in October 2001. Science operations began in February 2002. The mission is managed by JPL for NASA's Science Mission Directorate in Washington. Lockheed Martin Space Systems in Denver is the prime contractor for the project and built the spacecraft. NASA's Planetary Data System, sponsored by the Science Mission Directorate, archives and distributes scientific data from the agency's planetary missions, astronomical observations, and laboratory measurements.
For More Information Visit http://www.jpl.nasa.gov/news/news.cfm?release=2010-244
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11:23 PM
Gabriella Brianna
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NASA's Spitzer Space Telescope has at last found buckyballs in space, as illustrated by this artist's conception. Image credit: NASA/JPL-Caltech - Larger Image
Astronomers using NASA's Spitzer Space Telescope have discovered carbon molecules, known as "buckyballs," in space for the first time. Buckyballs are soccer-ball-shaped molecules that were first observed in a laboratory 25 years ago.
They are named for their resemblance to architect Buckminster Fuller's geodesic domes, which have interlocking circles on the surface of a partial sphere. Buckyballs were thought to float around in space, but had escaped detection until now.
"We found what are now the largest molecules known to exist in space," said astronomer Jan Cami of the University of Western Ontario, Canada, and the SETI Institute in Mountain View, Calif. "We are particularly excited because they have unique properties that make them important players for all sorts of physical and chemical processes going on in space." Cami has authored a paper about the discovery that will appear online Thursday in the journal Science.
Buckyballs are made of 60 carbon atoms arranged in three-dimensional, spherical structures. Their alternating patterns of hexagons and pentagons match a typical black-and-white soccer ball. The research team also found the more elongated relative of buckyballs, known as C70, for the first time in space. These molecules consist of 70 carbon atoms and are shaped more like an oval rugby ball. Both types of molecules belong to a class known officially as buckminsterfullerenes, or fullerenes.
The Cami team unexpectedly found the carbon balls in a planetary nebula named Tc 1. Planetary nebulas are the remains of stars, like the sun, that shed their outer layers of gas and dust as they age. A compact, hot star, or white dwarf, at the center of the nebula illuminates and heats these clouds of material that has been shed.
The buckyballs were found in these clouds, perhaps reflecting a short stage in the star's life, when it sloughs off a puff of material rich in carbon. The astronomers used Spitzer's spectroscopy instrument to analyze infrared light from the planetary nebula and see the spectral signatures of the buckyballs. These molecules are approximately room temperature -- the ideal temperature to give off distinct patterns of infrared light that Spitzer can detect. According to Cami, Spitzer looked at the right place at the right time. A century from now, the buckyballs might be too cool to be detected.
The data from Spitzer were compared with data from laboratory measurements of the same molecules and showed a perfect match.
"We did not plan for this discovery," Cami said. "But when we saw these whopping spectral signatures, we knew immediately that we were looking at one of the most sought-after molecules."
In 1970, Japanese professor Eiji Osawa predicted the existence of buckyballs, but they were not observed until lab experiments in 1985. Researchers simulated conditions in the atmospheres of aging, carbon-rich giant stars, in which chains of carbon had been detected. Surprisingly, these experiments resulted in the formation of large quantities of buckminsterfullerenes. The molecules have since been found on Earth in candle soot, layers of rock and meteorites.
The study of fullerenes and their relatives has grown into a busy field of research because of the molecules' unique strength and exceptional chemical and physical properties. Among the potential applications are armor, drug delivery and superconducting technologies.
Sir Harry Kroto, who shared the 1996 Nobel Prize in chemistry with Bob Curl and Rick Smalley for the discovery of buckyballs, said, "This most exciting breakthrough provides convincing evidence that the buckyball has, as I long suspected, existed since time immemorial in the dark recesses of our galaxy."
Previous searches for buckyballs in space, in particular around carbon-rich stars, proved unsuccessful. A promising case for their presence in the tenuous clouds between the stars was presented 15 years ago, using observations at optical wavelengths. That finding is awaiting confirmation from laboratory data. More recently, another Spitzer team reported evidence for buckyballs in a different type of object, but the spectral signatures they observed were partly contaminated by other chemical substances.
For More Information visit http://www.jpl.nasa.gov/news/news.cfm?release=2010-243
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11:22 PM
Gabriella Brianna
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During NASA's ICESCAPE voyage to the Arctic, scientists have been looking at the phytoplankton in the Arctic's Chukchi Sea -- how many, how big and at what depths they are found. But there are other ways of looking at these small life forms.
"We measure phytoplankton in terms of their pigments and light absorption properties," said Stan Hooker of NASA's Ocean Biology and Biogeochemistry Calibration and Validation Office at Goddard Space Flight Center, Greenbelt, Md. Hooker, Joaquin Chaves and Aimee Neeley, also of NASA, measure the color of the water. Anything in the water, plankton or not, can influence that color.
On July 2, a crane maneuvered a small boat halfway down the side of the U.S. Coast Guard Cutter Healy – the platform for the five-week ICESCAPE mission, NASA's first dedicated oceanographic field campaign, which is studying the physics, chemistry and biology of the ocean and sea ice within a changing Arctic.
Hooker, Chaves and Coast Guard crew boarded the small boat and readied for an expedition away from the stirred water and shadow of the 420-foot Healy. Lowered to the ocean surface, Hooker's team powered away, entering uncharted waters.
Maneuvering over smooth water and around chunks of sea ice, the small boat slowed to a stop near the edge of an ice floe.
"This is new for us because we usually haven't been able to work this close to the ice before," Hooker said. "Satellites can't measure near the ice, so we do this to help specify the next generation of equipment, and to contribute to the science objectives."
First over the side was a small red instrument that the crew dropped on a line into the ocean and then reeled by hand, as if wrangling a fish. Sensors on the instrument measured the wavelengths of sunlight at different depths - both what's coming into the ocean and what's reflected back out which is similar to what is "seen" by satellites.
Next the crew lowered a second, larger package of instruments into the depths of the ocean. One pair of sensors emits light and measures how much is scattered back. Another pair measures the fluorescence of chlorophyll and colored dissolved organic matter, an important distinction as both appear green to satellites.
Last, the crew collected water samples to be returned to the Healy for analysis in the lab.
"We can measure the changes in the color to find out what's happening with the ecology," said Greg Mitchell, a research biologist at Scripps Institution of Oceanography in San Diego, who analyzes the water samples. "We can relate color back to how much chlorophyll is in the ocean, how much algae biomass there is, and processes such as the rate of photosynthesis."
Similar, more frequent measurements are made from the Healy, which marked its one-hundredth ocean station of the mission on July 8. The small boat deploys less often -- almost daily -- but reaches more targeted regions.
"We do the measurements at sea in order to relate what's going on in the ocean with the optics," Mitchell said. "Then we apply those relationships to the optical data from the ocean color satellites and we can make estimates of processes and distributions globally."
Onboard the Healy to help scientists figure out where to sample is Bob Pickart, a physical oceanographer from Woods Hole Oceanographic Institution. Pickart can decipher water type and circulation to guide where to make measurements.
A great unknown, for example, is a picture of what's feeding the evolution of a "hotspot" in Barrow Canyon. Right now, winter water -- rich with nutrients -- has been carried across the shallow shelf where the Healy is surveying.
"This is a really interesting, important time of year," Pickart said. "As the ice recedes, productivity is starting and things are getting cranked up."
But for how long will these hotspots thrive? While this is dictated by light and nutrients, the circulation near Barrow and Herald canyons -- two fissures that channel water off the shelf -- plays a vitally important role as well.
On July 12, after a night of cutting through sea ice, ICESCAPE scientists caught a glimpse of the hotspot. As an instrument lowered from the Healy descended through the water, real-time fluorescence information showed low levels of chlorophyll.
Scientists on the Healy will analyze the hotspot data and water samples, but whether a plankton bloom has come and gone, the region remains a hotspot for ground-dwelling communities, according to Karen Frey of Clark University. Feeding off plankton that sink to the seafloor, species here are diverse and large. A single sample retrieved from the ocean floor turned up a large crab, sponges and a sea star.
Meanwhile, samples returned from the near-ice survey July 2 on the small boat are turning up mixed results – sometimes indicating the presence of phytoplankton communities and sometimes not, according to Atsushi Matsuoka, of Laboratoire d'Oceanographie de Villefranche. To find out why, his group will look at trends after returning home from ICESCAPE.
For more information visit http://www.nasa.gov/topics/earth/features/icescape2010_arctic_optics.html
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12:06 AM
Gabriella Brianna
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A downward-pointing camera on the front-left side of NASA's Curiosity rover will give adventure fans worldwide an unprecedented sense of riding a spacecraft to a landing on Mars.
The Mars Descent Imager, or MARDI, will start recording high-resolution video about two minutes before landing in August 2012. Initial frames will glimpse the heat shield falling away from beneath the rover, revealing a swath of Martian terrain below illuminated in afternoon sunlight. The first scenes will cover ground several kilometers (a few miles) across. Successive images will close in and cover a smaller area each second.
The full-color video will likely spin, then shake, as the Mars Science Laboratory mission's parachute, then its rocket-powered backpack, slow the rover's descent. The left-front wheel will pop into view when Curiosity extends its mobility and landing gear.
The spacecraft's own shadow, unnoticeable at first, will grow in size and slide westward across the ground. The shadow and rover will meet at a place that, in the final moments, becomes the only patch of ground visible, about the size of a bath towel and underneath the rover.
Dust kicked up by the rocket engines during landing may swirl as the video ends and Curiosity's surface mission can begin.
All of this, recorded at about four frames per second and close to 1,600 by 1,200 pixels per frame, will be stored safely into the Mars Descent Imager's own flash memory during the landing. But the camera's principal investigator, Michael Malin of Malin Space Science Systems, San Diego, and everyone else will need to be patient. Curiosity will be about 250 million kilometers (about 150 million miles) from Earth at that point. It will send images and other data to Earth via relay by one or two Mars orbiters, so the daily data volume will be limited by the amount of time the orbiters are overhead each day.
"We will get it down in stages," said Malin. "First we'll have thumbnails of the descent images, with only a few frames at full scale."
Subsequent downlinks will deliver additional frames, selected based on what the thumbnail versions show. The early images will begin to fulfill this instrument's scientific functions. "I am really looking forward to seeing this movie. We have been preparing for it a long time," Malin said. The lower-resolution version from thumbnail images will be comparable to a YouTube video in image quality. The high-definition version will not be available until the full set of images can be transmitted to Earth, which could take weeks, or even months, sharing priority with data from other instruments."
The Mars Descent Imager will provide the Mars Science Laboratory team with information about the landing site and its surroundings. This will aid interpretation of the rover's ground-level views and planning of initial drives. Hundreds of the images taken by the camera will show features smaller than what can be discerned in images taken from orbit.
"Each of the 10 science instruments on the rover has a role in making the mission successful," said John Grotzinger of the California Institute of Technology in Pasadena, chief scientist for the Mars Science Laboratory. "This one will give us a sense of the terrain around the landing site and may show us things we want to study. Information from these images will go into our initial decisions about where the rover will go."
The nested set of images from higher altitude to ground level will enable pinpointing Curiosity's location even before an orbiter can photograph the rover on the surface.
Malin said, "Within the first day or so, we'll know where we are and what's near us. MARDI doesn't do much for six-month planning -- we'll use orbital data for that -- but it will be important for six-day and 16-day planning."
In addition, combining information from the descent images with information from the spacecraft's motion sensors will enable calculating wind speeds affecting the spacecraft on its way down, an important atmospheric science measurement. The descent data will later serve in designing and testing future landing systems for Mars that could add more control for hazard avoidance.
After landing, the Mars Descent Imager will offer the capability to obtain detailed images of ground beneath the rover, for precise tracking of its movements or for geologic mapping. The science team will decide whether or not to use that capability. Each day of operations on Mars will require choices about how to budget power, data and time.
Last month, spacecraft engineers and technicians re-installed the Mars Descent Imager onto Curiosity for what is expected to be the final time, as part of assembly and testing of the rover and other parts of the Mars Science Laboratory flight system at NASA's Jet Propulsion Laboratory, Pasadena, Calif. Besides the rover itself, the flight system includes the cruise stage for operations between Earth and Mars, and the descent stage for getting the rover from the top of the Martian atmosphere safely to the ground.
Malin Space Science Systems delivered the Mars Descent Imager in 2008, when NASA was planning a 2009 launch for the mission. This camera shares many design features, including identical electronic detectors, with two other science instruments the same company is providing for Curiosity: the Mast Camera and the Mars Hand Lens Imager. The company also provided descent imagers for NASA's Mars Polar Lander, launched in 1999, and Phoenix Mars Lander, launched in 2007. However, the former craft was lost just before landing and the latter did not use its descent imager due to concern about the spacecraft's data-handling capabilities during crucial moments just before landing.
For More information visit http://www.jpl.nasa.gov/news/news.cfm?release=2010-239
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9:34 PM
Gabriella Brianna
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This image shows the famous Pleiades cluster of stars as seen through the eyes of WISE, or NASA's Wide-field Infrared Survey Explorer. The mosaic contains a few hundred image frames -- just a fraction of the more than one million WISE has captured so far as it completes its first survey of the entire sky in infrared light. Image credit: NASA/JPL-Caltech/UCLA - Larger Image
NASA's Wide-field Infrared Survey Explorer, or WISE, will complete its first study of the entire sky on July 17, 2010. The mission has generated more than one million images so far, of everything from asteroids to distant galaxies.
"Like a globe-trotting shutterbug, WISE has completed a world tour with 1.3 million slides casing the whole sky," said Edward Wright, the principal investigator of the mission at the University of California, Los Angeles.
Some of these images have been processed and stitched together into a novel picture being released today. It shows the Pleiades cluster of stars, also known as the Seven Sisters, resting in a tangled bed of wispy dust. The pictured region covers seven square degrees, or an area equal to 35 full moons, highlighting the telescope's ability to take wide shots of vast regions of space.
The new picture was taken in February. It shows infrared light from WISE's four detectors in a range of wavelengths. This infrared vision highlights the region's expansive dust cloud, through which the Seven Sisters and other stars in the cluster are passing. Infrared light also reveals the smaller and cooler stars of the family.
"The WISE all-sky survey is helping us sift through the huge and diverse population of celestial objects," said Hashima Hasan, WISE Program scientist at NASA Headquarters in Washington. "It's a great example of the high impact science that's likely from NASA's Explorer Program."
The first release of WISE data, covering about 80 percent of the sky, will be delivered to the astronomical community in May of next year. The mission scanned strips of the sky as it orbited around the Earth's poles since its launch last December. WISE always stays over the Earth's day-night line. As the Earth moves around the sun, innovative slices of sky come into the telescope's field of view. It has taken six months, or the amount of time for Earth to travel halfway around the sun, for the mission to complete one full scan of the entire sky.
For the next three months, the mission will map half of the sky again. This will improve the telescope's data, revealing more hidden asteroids, stars and galaxies. The mapping will give astronomers a look at what's changed in the sky. The mission will end when the instrument's block of solid hydrogen coolant, desirable to chill its infrared detectors, runs out.
"The eyes of WISE have not blinked since launch," said William Irace, the mission's project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Both our telescope and spacecraft have performed flawlessly and have imaged every corner of our universe, just as we planned."
So far, WISE has observed more than 100,000 asteroids, both known and formerly unseen. Most of these space rocks are in the main belt between Mars and Jupiter. However, some are near-Earth objects, asteroids and comets with orbits that pass relatively close to Earth. WISE has discovered more than 90 of these new near-Earth objects. The infrared telescope is also good at spotting comets that orbit far from Earth and has discovered more than a dozen of these so far.
WISE's infrared vision also gives it a exceptional ability to pick up the glow of cool stars, called brown dwarfs, in addition to distant galaxies bursting with light and energy. These galaxies are called ultra-luminous infrared galaxies. WISE can see the brightest of them.
"WISE is filling in the blanks on the infrared properties of everything in the universe from nearby asteroids to distant quasars," said Peter Eisenhardt of JPL, project scientist for WISE. "But the most thrilling discoveries may well be objects we haven't yet imagined exist."
JPL manages the Wide-field Infrared Survey Explorer for NASA's Science Mission Directorate in Washington. The mission was selected under NASA's Explorers Program managed by the Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah, and the spacecraft was built by Ball Aerospace & Technologies Corp., in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.
For More information visit http://www.jpl.nasa.gov/news/news.cfm?release=2010-238
9:42 PM
Gabriella Brianna
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Astronomers using NASA's Hubble Space Telescope have established the existence of a baked object that could be called a "cometary planet." The gas giant planet, named HD 209458b, is orbiting so close to its star that its heated atmosphere is escaping into space.
Observations taken with Hubble's Cosmic Origins Spectrograph (COS) propose powerful stellar winds are sweeping the cast-off atmospheric material behind the parched planet and shaping it into a comet-like tail.
"Since 2003 scientists have theorized the lost mass is being pushed back into a tail, and they have even intended what it looks like," said astronomer Jeffrey Linsky of the University of Colorado in Boulder, leader of the COS study. "We think we have the best observational proof to support that theory. We have measured gas coming off the planet at specific speeds, some coming toward Earth. The most likely interpretation is that we have measured the velocity of material in a tail."
The planet, located 153 light-years from Earth, weighs slightly less than Jupiter but orbits 100 times closer to its star than the Jovian giant. The roasted planet zips about its star in a short 3.5 days. In contrast, our solar system's best planet, Mercury, orbits the Sun in 88 days. The extrasolar planet is one of the most intensely scrutinized, because it is the first of the few known alien worlds that can be seen transitory in front of, or transiting, its star. Linsky and his team used COS to examine the planet's atmosphere during transiting events. During a transit, astronomers study the structure and chemical makeup of a planet's atmosphere by sampling the starlight that passes through it. The dip in starlight because of the planet's passage, without the atmosphere, is very small, only about 1.5 percent. When the atmosphere is added, the dip jumps to 8 percent, indicating a bloated atmosphere.
COS detected the heavy elements carbon and silicon in the planet's super-hot, 2,000-degree-Fahrenheit atmosphere. This detection exposed the parent star is heating the entire atmosphere, dredging up the heavier elements and allowing them to escape the planet.
The COS data also showed the material leaving the planet was not all traveling at the same speed. "We found gas escaping at high velocities, with a great amount of this gas flowing toward us at 22,000 miles per hour," Linsky said. "This large gas flow is probable gas swept up by the stellar wind to form the comet-like tail trailing the planet."
Hubble's latest spectrograph has the ability to probe a planet's chemistry at ultraviolet wavelengths not accessible to ground-based telescopes. COS is proving to be an important instrument for probing the atmospheres of "hot Jupiters" like HD 209458b.
Another Hubble instrument, the Space Telescope Imaging Spectrograph (STIS), observed the planet in 2003. The STIS data showed an active, evaporating atmosphere, and a comet-tail-like structure was optional as a possibility. But STIS wasn't able to obtain the spectroscopic detail necessary to show a tail, or an Earthward-moving component of the gas, during transits. The tail was detected for the first time because of the unique combination of very high ultraviolet sensitivity and good spectral resolution provided by COS.
Although this extreme planet is being roasted by its star, it won't be destroyed anytime soon. "It will take about a trillion years for the planet to evaporate," Linsky said.
The results appeared in the July 10 issue of The Astrophysical Journal.
The Hubble Space Telescope is a project of global cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI) conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc. in Washington, D.C.
For more information visit http://www.nasa.gov/mission_pages/hubble/science/planet-tail.html
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3:29 AM
Gabriella Brianna
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Most of us take it for granted today that American astronauts and Russian cosmonauts live and work together in Earth orbit. They've been doing it for years, first in the Shuttle-Mir program, and now on the International Space Station.
But before the two Cold War-rivals first met in orbit in 1975, such a partnership seemed unlikely. Since Sputnik bleeped into orbit in 1957, the superpowers were driven by the Space Race, with the U.S. and then-Soviet Union driven more by competition than cooperation. When President Kennedy called for a manned moon landing in 1961, he spoke of "battle that is now going on around the world between freedom and tyranny" and referred to the "head start obtained by the Soviets with their large rocket engines."
Watch the Apollo-Soyuz docking and crew handshake:
But by the mid-70s things had changed. The U.S. had "won" the race to the Moon, with six Apollo landings between 1969 and 1972. Both nations had launched space stations, the Russian Salyut and American Skylab. With the Space Shuttle still a few years off and the diplomatic chill thawing, the time was right for a joint mission.
The Apollo-Soyuz Test Project would send NASA astronauts Tom Stafford, Deke Slayton and Vance Brand in an Apollo Command and Service Module to meet Russian cosmonauts Aleksey Leonov and Valeriy Kubasov in a Soyuz capsule. A jointly designed, U.S.-built docking module fulfilled the main technical goal of the mission, demonstrating that two dissimilar craft could dock in orbit. But the human side of the mission went far beyond that.
The training leading up to the mission exposed the two crews to each other's nations, helping to break down cultural and language barriers. As Brand said in a 2000 interview, amid the Cold War tensions, "we thought they were pretty aggressive people and ... they probably thought we were monsters. So we very quickly broke through that, because when you deal with people that are in the same line of work as you are, and you’re around them for a short time, why, you discover that, well, they're human beings."
In a 1997 interview, Stafford described how they got around the language problem. "Each crew would speak his own language, and the other would have to understand," he said. It just wasn't working, until Stafford and the Russian backup commander had the idea to speak in the other's language. "So we started," he said, "and boy, it worked slick as a whistle."
'Hello, Darlin'
On July 17, 1975, the five explorers and the two craft --launched two days before -- approached each other for docking. As Stafford guided the Apollo forward, Soyuz commander Leonov quipped "Tom, please don't forget about your engine." Just after noon on the East Coast in the U.S., with a live TV audience watching, the two craft finally met. "Soyuz and Apollo are shaking hands now."
A few hours later it was the crew members who were literally shaking hands, exchanging hugs and ceremonial gifts, including U.S., Soviet and United Nations flags, commemorative plaques, medallions, certificates and tree seeds.
The crews received a congratulatory message from Soviet premier Leonid Brezhnev and a phone call from U.S. President Gerald Ford, who joked with astronaut Slayton about being the "world's oldest space rookie."
President Ford calls the crew:
The 51-year old Slayton had been one of the "Original Seven" Mercury astronauts, but was grounded due to a heart condition. Finally cleared to fly on Apollo-Soyuz, Slayton reported, "it's been a great experience. I don't think there's any way anybody can express how beautiful it is up here."
Apollo Commander Stafford had another unique cultural exchange for the cosmonauts. He'd gotten country music star Conway Twitty to record "Privet Radost," a Russian version of his hit "Hello, Darlin'." About an hour before the two craft undocked, the song was played from orbit and heard all over the world. Mission Control quipped that it "sounded like it was from far Western Oklahoma, around Kiev."
The Apollo crew returned to Earth on July 19, their Russian counterparts two days later. It would be two decades until the countries teamed up again with the Shuttle-Mir program, but the seed was planted. As Brand said, "I really believe that we were sort of an example … to the countries. We were a little of a spark or a foot in the door that started better communications."
For more information visit http://www.nasa.gov/topics/history/features/astp_35.html
10:13 PM
Gabriella Brianna
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Trunks of living trees can be seen two years after a powerful 2005 storm toppled many neighboring trees, tearing open the ordinarily closed, green canopy of this stretch of Amazon forest near Manaus, Brazil - Larger image
A single, huge, violent storm that swept across the whole Amazon forest in 2005 killed half a billion trees, according to a original study funded by NASA and Tulane University, New Orleans.
While storms have long been predictable as a cause of Amazon tree loss, this study is the first to really quantify losses from a storm. And the losses are much greater than formerly suspected, say the study's authors, which comprise research scientist Sassan Saatchi of NASA’s Jet Propulsion Laboratory, Pasadena, Calif. The work suggests that storms may play a larger role in the dynamics of Amazon forests than previously recognized, they add.
Previous research had attributed a peak in tree humanity in 2005 solely to a severe drought that affected parts of the forest. The new study says that a single squall line (a long line of severe thunderstorms, the kind associated with lightning and heavy rainfall) had a significant role in the tree demise. Research suggests this type of storm might become more common in the future in the Amazon due to climate change, killing a higher number of trees and releasing more carbon to the atmosphere.
Tropical thunderstorms have long been suspected of wreaking havoc in the Amazon, but this is the first time researchers have intended how many trees a single thunderstorm can kill, says Jeffrey Chambers, a forest ecologist at Tulane University and one of the authors of the paper. The paper has been conventional for publication in Geophysical Research Letters, a journal of the American Geophysical Union.
Previous studies by a coauthor of this new paper, Niro Higuchi of Brazil's National Institute for Amazon Research (INPA), showed the 2005 tree mortality spike was the second largest recorded since 1989 for the Manaus region in the Central Amazon. Also in 2005, large parts of the Amazon forest experienced one of the harshest droughts of the last century. A study published in the journal Science in 2009 piercing to the drought as the single agent for a basin-wide increase in tree mortality. But a very large area with major tree loss (the region near Manaus) was not affected by the drought.
"We can't attribute [the increased] mortality to just drought in certain parts of the basin--we have solid confirmation that there was a strong storm that killed a lot of trees over a large part of the Amazon," Chambers says.
From Jan. 16 to 18, 2005, a squall line 1,000 kilometers (620 miles) long and 200 kilometers (124 miles) wide crossed the whole Amazon basin from southwest to northeast, causing numerous human deaths in the cities of Manaus, Manacaparu, and Santarem. The strong vertical winds connected with the storm, blowing up to 145 kilometers per hour (90 miles per hour), uprooted or snapped in half trees that were in their path. In many cases, the stricken trees took down some of their neighbors when they fell.
The researchers used a combination of Landsat satellite images, field-measured tree mortality, and modeling to decide the number of trees killed by the storm. By linking satellite data to observations on the ground, the researchers were able to take into description smaller tree blowdowns (less than 10 trees) that otherwise cannot be detected through satellite images.
Looking at satellite images for the area of Manaus from before and after the storm, the researchers detected changes in the reflectivity of the forest, which they supposed were indicative of tree losses. Undisturbed forest patches appeared as closed, green canopy in satellite images. When trees die and fall, a clearing opens, exposing wood, dead vegetation, and surface litter. This so-called "woody signal" only lasts for about a year in the Amazon. In a year, vegetation re-grows and covers the exposed wood and soil. This means the signal is a good indicator of recent tree deaths.
After seeing disturbances in the satellite images, the researchers established five field sites in one of the blowdown areas, and counted the number of trees that had been killed by the storm; researchers can typically tell what killed a tree from looking at it.
"If a tree dies from a drought, it generally dies standing. It looks very unlike from trees that die snapped by a storm," Chambers says.
In the most affected plots, near the centers of large blowdowns, up to 80 percent of the trees had been killed by the storm.
By comparing their field data and the satellite observations, the researchers determined that the satellite images were accurately pinpointing areas of tree death, and they intended that the storm had killed between 300,000 and 500,000 trees in the area of Manaus. The number of trees killed by the 2005 storm is equivalent to 30 percent of the annual deforestation in that same year for the Manaus region, which experiences relatively low rates of deforestation.
The team then extrapolated the results to the whole Amazon basin.
"We know that the storm was intense and went across the basin," Chambers says. "To quantify the possible basin-wide impact, we assumed that the whole area impacted by the storm had a similar level of tree mortality as the mortality observed in Manaus."
The researchers estimate that between 441 and 663 million trees were destroyed across the whole basin. This represents a loss equivalent to 23 percent of the expected mean annual carbon accumulation of the Amazon forest.
Squall lines that move from southwest to northeast of the forest, like the one in January 2005, are relatively rare and poorly studied, says Robinson Negron-Juarez, an atmospheric scientist at Tulane University, and lead author of the study. Storms that are similarly destructive but advance in the opposite direction (from the northeast coast of South America to the interior of the continent) occur up to four times per month. They can also generate large forest blowdowns (contiguous patches of wind-toppled trees), although it's infrequent that either of these two types of storms crosses the whole Amazon.
"We need to start measuring the forest perturbation caused by both types of squall lines, not only by the ones impending from the south," Negron-Juarez says. "We need that data to estimate total biomass loss from these natural events, which has never been quantified."
Chambers says that authors of preceding studies on tree mortality in the Amazon have diligently collected dead-tree tolls, but information on exactly what killed the trees is often lacking, or not reported.
"It's very important that when we collect data in the field, we do forensics on tree mortality," says Chambers, who has been studying forest ecology and carbon cycling in the Amazon since 1993. "Under a changing climate, some forecasts say that storms will increase in strength. If we start seeing increases in tree mortality, we need to be able to say what's killing the trees."
For more information visit http://www.jpl.nasa.gov/news/news.cfm?release=2010-232
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10:12 PM
Gabriella Brianna
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The High-Resolution Imaging Science Experiment aboard NASA’s Mars Reconnaissance Orbiter provides this view of Olympus Mons, the tallest known volcano in the solar system. Image credit: NASA/JPL/Microsoft/University of Arizona - Larger Image
Today, Microsoft Research and NASA are given that an entirely new experience to users of the WorldWide Telescope, which will allow visitors to interact with and investigate our solar system like never before. Viewers can now take elite interactive tours of the red planet, hear directly from NASA scientists, and view and explore the most absolute, highest-resolution coverage of Mars available. To experience Mars up close, Microsoft and NASA encourage viewers to download the new WWT|Mars experience at http://www.worldwidetelescope.org.
Dan Fay, director of Microsoft Research’s Earth, Energy and Environment effort, works with scientists around the world to see how technology can help resolve their research challenges. Since early 2009, he’s been working with NASA to bring imagery from the agency’s Mars and Moon missions to life, and to make their precious volumes of information more accessible to the masses.
“We wanted to make it easier for people everywhere, as well as scientists, to entrée these unique and valuable images,” says Fay. “NASA had the images and they were open to new ways to share them. Through the WorldWide Telescope we were able to construct a user interface at WWT|Mars that would permit people to take advantage of the great content they had.”
To create the new Mars experience in the WorldWide Telescope, Fay worked closely with Michael Broxton of the NASA Ames Research Center’s Intelligent Robotics Group (IRG). Broxton leads a team in the IRG easily called the Mapmakers, which applies computer vision and image processing to problems of cartography. Over the years, the Mapmakers have taken satellite images from Mars, the moon and elsewhere, and turned them into useful maps. Broxton says that getting the results of NASA’s work out to the public is an important part of his mission.
“NASA has a history of providing the public with access to our spacecraft imagery,” he says. “With projects like the WorldWide Telescope, we’re working to offer greater access so that future generations of scientists can discover space in their own way.”
It is the mission of Fay’s team at Microsoft to push the boundaries of technology in service of scientific discovery and proceed the state of the art in computer science overall. He explains that the approach to the Mars WorldWide Telescope project was to give information at your fingertips. As such, Fay says the WorldWide Telescope is as much a research project as a Web service — one that has resulted in a truly stellar experience for users.
“We were able to take the imagery from NASA, unite it with their altitude models and lay those onto the surface of the globe of Mars,” Fay says. “Now users of the WorldWide Telescope can zoom down and actually experience the surface-level detail of Mars. They can pan back and see the height of the craters or the depth of the canyons. The new Mars experience allows people to feel as though they’re actually there.”
In particular, there’s a new dataset from the University of Arizona’s High Resolution Imaging Science Experiment (HiRISE), a state-of-the-art, remote-sensing camera on NASA’s Mars Reconnaissance Orbiter. HiRISE collects incredible images of super high resolution — a quarter of a meter per pixel on average. Each HiRISE image is a gigapixel in size, containing 100 times as much information as a 10 megapixel off-the-shelf camera.
“Due to its size, the data set is too bulky for many people to work with,” notes Fay. “But that large data set is necessary to provide the most in-depth experience — the most beautiful images, which are full of information. We needed this immense level of data to even begin to attempt to create this unique Mars experience.”
To get those images out to the public in a new way, the team set an striving goal to take all of the HiRISE images, 13,000 or so, and stitch them onto a single coherent map. While HiRISE has only imaged about 1 percent of Mars, leaving vast regions of Mars still to be explored, all of the HiRISE images have now been geolocated on a single map, and connected with other global Mars data sets. Dotted with HiRISE images acquired so far, this new coherent map is the highest-resolution map of Mars’ surface ever constructed.
“Not only is it going to be amazing for the all-purpose public to see, but it’s actually something that scientists have never been able to see before,” Broxton says. “This particular feat has never been attempted.”
The reason for that, he says, is the technical challenge behind the project. The resolution of the images is so high and the files so large that NASA has been crunching the raw data for three years now. For anyone who’s ever tried to edit a picture from a digital camera and had the computer spin on it for several seconds, multiply that by 100, or more. And then multiply the number of images by 13,000. Multiply the number of tasks by an additional dozen and you can begin to see why the process has never been attempted. Broxton leveraged Nebula, NASA’s high-performance computing cloud, to process the image data. In all, the HiRISE mosaic took 14 days to process on 114 CPUs and constitutes the entire collection that has been taken by the orbiting camera as of May 2010.
“It’s an indispensible archive of information, but it’s not very easy to access unless you have an expertise in processing lots of data,” Broxton says. “Nebula allowed us to take the data, process it into a format appropriate for the WorldWide Telescope, and then make the entire catalog of NASA’s Mars information obtainable on desktops around the world through the WorldWide Telescope.”
The images themselves reside on the Nebula cloud at the NASA Ames Research Center, near San José, California. Fay says hosting the data offsite is not a new come near, but rather one that allows WorldWide Telescope to use imagery from just about anyone. Thanks to the magic of the cloud, other imagery on the site is hosted at Microsoft datacenters around the world. Hubble’s resides in Baltimore. The California Institute of Technology’s is in Pasadena.
“Anyone can really put up their own astronomical images and view them through WorldWide Telescope,” says Fay. “We’ve worked with folks at several other institutions to make their images available.”
Retrieving images from all over the world is as smooth as any experience on the Web today. The secret is a tiling system that uses the visitor’s desktop computer to practice the imagery. With such a huge amount of information contained in one coherent tool, users are able to browse and zoom into attractive locations as they please. Visitors to the WorldWide Telescope can now have the experience of flying though a 3-D rendering of Victoria Crater and Olympus Mons — a low valley and the highest peak in our solar system — and can experience firsthand the tremendous elevation and intricate features on the Martian surface.
“We take advantage of the computing power you have on your desktop to allow a smooth, 3-D experience,” explains Fay. “As you zoom in, it’s a really constant view of these images. You can now get a true sense for what the terrain looks like.”
Broxton says the 3-D effect is derived from information provided by an instrument called MOLA, the Mars Orbiter Laser Altimeter, which measured altitude along the surface of Mars from space from NASA’s Mars Global Surveyor orbiter. The team also shared that information with a stereo image-reconstruction process — taking two images from different angles and using that to build a 3-D model of the terrain.
“These images give you a predominantly visceral impression of, for example, the Mars Exploration Rover landing sites,” Broxton says. “You can see what it’s like in the hills there or zoom into surface craters. It’s really amazing stuff.”
For scientists and hardcore hobbyists, Fay’s team at Microsoft has urbanized another feature that puts the image in the context of the mission from which it was collected. Users can right-click on some of the images and find their original Web pages at NASA with additional details on the HiRISE project.
“So it’s not just the imagery, but bringing it together with the context,” Fay says. “We think that ability will make this an exciting tool for scientists and educators.”
So what is the surface of Mars like? According to Broxton, part of what’s striking about Mars is its resemblance to what we’re used to here on Earth. Mars shares many of the same Aeolian (wind), tectonic, volcanic and even water processes, the effects of which are visible on the planet’s surface.
“I often think of Mars as being a beautiful, barren, sculpted desert much like the American Southwest,” Broxton says. “On earth, most of our craters have been erased because we have a much more active tectonic and volcanic process, but aside from that, there’s a lot of similarity.”
Back on Earth, Fay and his team are already looking at ways to maintain building the WorldWide Telescope as a platform for advancing scientific learning, and a showcase for how technology can help assist understanding. He says that when he recently showed the new features to his son, the importance of that mission hit home.
“It gave my young son a sense of what the space mission is about, and why we as a nation invest in it,” he says. “I think that people who look at this will be amazed by these images and the detail of what these cameras can pick up. Seeing the solar system spinning in time, the details of the Martian planet, you could spend hours getting lost in space.”
For More information visit http://www.nasa.gov/topics/nasalife/features/microsoft_ww_telescope.html
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9:17 PM
Gabriella Brianna
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NASA-funded researchers monitoring Greenland's Jakobshavn Isbrae glacier report that a 7 square kilometer (2.7 square mile) section of the glacier broke up on July 6 and 7, as shown in the picture above. The calving front – where the ice sheet meets the ocean – retreated nearly 1.5 kilometers (a mile) in one day and is now additional inland than at any time formerly observed. The chunk of lost ice is roughly one-eighth the size of Manhattan Island, New York.
Research teams led by Ian Howat of the Byrd Polar Research Center at Ohio State University and Paul Morin, director of the Antarctic Geospatial Information Center at the University of Minnesota have been monitoring satellite images for changes in the Greenland ice sheet and its outlet glaciers. While this week's breakup itself is not curious, Howat noted, detecting it within hours and at such fine detail is a new phenomenon for scientists.
"While there have been ice breakouts of this magnitude from Jakonbshavn and other glaciers in the past, this event is interested because it occurs on the heels of a warm winter that saw no sea ice form in the surrounding bay," said Thomas Wagner, cryospheric program scientist at NASA Headquarters. "While the exact relationship between these events is being determined, it lends credence to the theory that warming of the oceans is accountable for the ice loss observed throughout Greenland and Antarctica."
The researchers relied on imagery from several satellites, including Landsat, Terra, and Aqua, to get a broad view of ice changes at both poles. Then, in the days leading up to the breakup, the team conventional images from DigitalGlobe's WorldView 2 satellite showing large cracks and crevasses forming.
DigitalGlobe Inc. provides the images as part of a public-private partnership with U.S. scientists. Howat and Morin are getting near-daily satellite updates from the Jakobshavn, Kangerlugssuaq, and Helheim glaciers (among the islands largest) and weekly updates on smaller outlet glaciers.
Jakobshavn Isbrae is located on the west coast of Greenland at latitude 69°N and has been retreated more than 45 kilometers (27 miles) over the past 160 years, 10 kilometers (6 miles) in just the past decade. As the glacier has retreated, it has broken into a northern and southern branch. The breakup this week occurred in the north branch.
Scientists estimation that as much as 10 percent of all ice lost from Greenland is coming through Jakobshavn, which is also supposed to be the single largest contributor to sea level rise in the northern hemisphere. Scientists are more anxious about losses from the south branch of the Jakobshavn, as the topography is flatter and lower than in the northern branch.
In addition to the remote sensing work, Howat, Morin, and other researchers have been funded by NASA and the National Science Foundation to plant GPS sensors, cameras, and other scientific equipment on top of the ice sheet to monitor changes and comprehend the fundamental workings of the ice. NASA also has been conducting twice-yearly airborne campaigns to the Arctic and Antarctic through the IceBridge program and measuring ice loss with the ICESat and GRACE satellites.
For more information visit http://www.nasa.gov/topics/earth/features/jakobshavn2010.html
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12:20 AM
Gabriella Brianna
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A dragon-shaped cloud of dust seems to fly out from a bright explosion in this infrared light image (bottom) from NASA's Spitzer Space Telescope, a creature that is entirely cloaked in shadow when viewed in visible part of the spectrum (top). Image credit: NASA/JPL-Caltech/Penn State/DSS - Full Image and captionA dragon-shaped cloud of dust seems to fly with the stars in a novel image from NASA's Spitzer Space Telescope (bottom). In visible light (top), the creature disappears into the clouds -- perhaps it's "frolicking in the autumn mist" like Puff, the Magic Dragon, from the well-known Peter, Paul and Mary song.
The infrared image has exposed that this creature, a dark cloud called M17 SWex, is forming stars at a furious rate but has not yet spawned the most massive type of stars, known as O stars. Such stellar behemoths, however, light up the M17 nebula at the image's center and have also blown a huge "bubble" in the gas and dust that forms M17's shining left edge.
The stars and gas in this region are now passing though the Sagittarius spiral arm of the Milky Way (moving from right to left), touching off a galactic "domino effect." The youngest episode of star formation is playing out inside the grimy dragon as it enters the spiral arm. Over time, this area will flare up like the bright M17 nebula, glowing in the light of young massive stars. An older burst of star formation blew the bubble seen in the region to the far left, called M17 EB.
The visible-light view of the area clearly shows the bright M17 nebula, as well as the lustrous hot gas filling the "bubble" to its left. However the M17 SWex "dragon" is hidden within dust clouds that are opaque to visible light. It takes an infrared view to catch the light from these shrouded regions and expose the earliest stages of star formation.
The bottom image is a three-color composite that shows infrared observations from two Spitzer instruments. Blue represents 3.6-micron light and green shows light of 8 microns, both captured by Spitzer's infrared array camera. Red is 24-micron light detected by Spitzer's multiband imaging photometer. The bottom visible-light image is a composite of visible-light data from the Digitized Sky Survey (DSS) from the UK Schmidt telescope. The image combines two observations that symbolize the blue and red light from the region.
For a more detailed feature story about the science in this image, visit http://www.spitzer.caltech.edu/news/1143.
This image was taken before Spitzer ran out of its liquid coolant in May 2009, beginning its warm mission.
NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA.
For More information visit http://www.jpl.nasa.gov/news/news.cfm?release=2010-225
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