NASA Extends Engineering and Scientific Services Contract

CLEVELAND -- NASA's Glenn Research Center has awarded a one-year contract option to Arctic Slope Regional Corporation (ASRC) of Greenbelt, Md., for engineering and scientific services. The option has a value that will not exceed $50 million.

The contract provides engineering and scientific support services to Glenn's Lewis Field and Plum Brook Station in Sandusky, Ohio. ASRC will provide on-site support services for technical, engineering and scientific tasks in the areas of aeronautics, microgravity science, space exploration, space power and propulsion, and related science and technology activities.

The modification increases the total value of the contract to $200 million. The extension begins Sept. 1, 2009. It is the second of three one-year options provided for in the original contract, awarded in August 2006.

For more information on NASA's Glenn Research Center, visit:

http://www.nasa.gov/glenn

For more information about NASA and agency programs, visit:

http://www.nasa.gov

NASA to Brief Media about Completion of Orion Vehicle Design Review

WASHINGTON -- NASA will host a teleconference Tuesday, Sept. 1, at 3 p.m. EDT to discuss the conclusion of the preliminary design review for the Orion crew exploration vehicle.

The preliminary design review is one of a series of reviews that occurs before hardware manufacturing may begin. As the review process progresses, detailed parts of the vehicle design are assessed to ensure the overall system can meet all NASA requirements for safe and reliable flight. The Orion Project's review process culminates in a board meeting held at NASA's Johnson Space Center in Houston beginning Aug. 31.

The briefing participants are:
-Geoff Yoder, director, Constellation Systems Division, NASA Headquarters, Washington
-Jeff Hanley, manager, Constellation Program, NASA's Johnson Space Center
-Mark Geyer, manager, Orion Project, NASA's Johnson Space Center

Reporters should contact Grey Hautaluoma at 202-358-0668, or Ashley Edwards at 202-358-1756, by noon Sept. 1 for dial-in information.

To listen to live streaming audio of the call, visit:

http://www.nasa.gov/newsaudio

For more information about the Orion crew exploration vehicle, visit:

http://www.nasa.gov/orion

For more information visit nasa.gov

Warped Debris Disks Around Stars Are Blowin’ in the Wind

The dust-filled disks where new planets may be forming around other stars occasionally take on some difficult-to-understand shapes. Now, a team led by John Debes at NASA's Goddard Space Flight Center in Greenbelt, Md., finds that a star's motion through interstellar gas can account for many of them.

"The disks contain small comet- or asteroid-like bodies that may grow to form planets," Debes said. "These small bodies often collide, which produces a lot of fine dust." As the star moves through the galaxy, it encounters thin gas clouds that create a kind of interstellar wind. "The small particles slam into the flow, slow down, and gradually bend from their original trajectories to follow it."

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This movie compares a Hubble image of the debris disk around HD 61005, a young star located 100 light-years away in the constellation Puppis, to a three-dimensional model based on gas drag. Credit: NASA/J. Debes, M. Kuchner (GSFC) and A. Weinberger (CIW)

Far from being empty, the space between stars is filled with patchy clouds of low-density gas. When a star encounters a relatively dense clump of this gas, the resulting flow produces a drag force on any orbiting dust particles. The force only affects the smallest particles - those about one micrometer across, or about the size of particles in smoke.

"This fine dust is usually removed through collisions among the particles, radiation pressure from the star's light and other forces," explained Debes. "The drag from interstellar gas just takes them on a different journey than they otherwise would have had."

The inner, yellow portion of HD 61005's disk spans 5.4 billion miles, or about the width of Neptune's orbit in our own solar system. This false-color Hubble view masks the star's direct light to bring out detail in the disk. Credit: NASA/ESA/D. Hines (Space Science Inst., New Mexico) and G. Schneider (Univ. of Arizona)

Working with Alycia Weinberger at the Carnegie Institution of Washington and Goddard astrophysicist Marc Kuchner, Debes was using the Hubble Space Telescope to investigate the composition of dust around the star HD 32297, which lies 340 light-years away in the constellation Orion. He noticed that the interior of the dusty disk -- a region comparable in size to our own solar system -- was warped in a way that matched a previously known warp at larger distances.

"Other research indicated there were interstellar gas clouds in the vicinity," Debes said. "The pieces came together to make me think that gas drag was a good explanation for what was going on."

"It looks like interstellar gas helps young planetary systems shed dust much as a summer breeze helps dandelions scatter seeds," Kuchner said.

As dust particles respond to the interstellar wind, a debris disk can morph into peculiar shapes determined by the details of its collision with the gas cloud. In a face-on encounter, such as that of the star HD 61005 in the constellation Puppis, the disk's edge bends gently away from the direction of motion. Fine dust trails behind, forming a cylindrical wake. If the disk instead slices edgewise through interstellar gas, the resulting headwind blows away fine dust from the portion inside the cloud, resulting in a lop-sided disk.

"The drag from interstellar gas only affects the outskirts of the disk, where the star's gravity can't really hold onto the material," Weinberger said.

The systems studied are about 100 million years old and resemble our own solar system shortly after the major planets formed. Although astronomers don't know whether planets lurk within the disks of these systems, a better understanding of processes affecting a disk's outer regions will shed light on how "ice giant" planets like Uranus and Neptune -- and the more distant swarm of small, icy bodies known as the Kuiper Belt -- formed within the solar system.

Astronomers have sometimes attributed warps and bends in debris disks to the presence of undiscovered planets or to past encounters with another star. "But we expect interstellar gas to be around -- it's everywhere," Debes said. "It's important to consider the ecology of these debris disks before running to such conclusions, and this model explains a lot of the weirdly shaped disks we see."

A paper describing the model appears in the September 1 issue of The Astrophysical Journal.

Related link:

NASA Supercomputer Shows How Dust Rings Point to Exo-Earths
http://www.nasa.gov/centers/goddard/news/topstory/2008/dust_rings.html

Francis Reddy
NASA's Goddard Space Flight Center

For more information visit nasa.gov

Model Car, Airplane Highlight Discovery Crew

The real space shuttle will carry a model of itself into space during the STS-128 mission. It is just one part of the cargo manifest assembled by the seven astronauts of Discovery to help mark their personal achievements and community ties.

The model shuttle is 7 inches long and represents the Montpelier Elementary School of Montpelier, Ind., the hometown of Discovery Pilot Kevin Ford, who is making his first flight. The shuttle model has plenty of company, including an Indiana flag and a red model car from the Indianapolis Motor Speedway, home of the Indianapolis 500.

There’s also a green ceramic airplane representing Notre Dame's Department of Aerospace and Mechanical Engineering, and a 6 1/2-inch metal airplane piece from the Mission Aviation Fellowship of Nampa, Idaho. .

Discovery’s lockers also will take an assortment of medallions on its flight to the International Space Station. The crew members have included commemoratives from various organizations, including the U.S. Army's 3rd Aviation Regiment and 3rd Infantry Division, the 16th Congressional District and the Houston Astros. A replica of the Nobel Peace Prize also is making the trip into space.

Mission patches are always popular items to fly on a shuttle. This one is particularly valuable because it is part of the flight suit that Jose Hernandez will wear during launch and landing. Credit: NASA/Kim Shiflett

Astronauts are allowed to take small items into space with them to celebrate their achievements and connections. Some of the items remain in personal collections after they return to Earth, while many find public homes around the world as mementos of exploration and inspiration.

Veteran astronaut Patrick Forrester’s class of 1979 from the U.S. Military Academy at West Point is highlighted in the commemoratives by a gold medallion.

First-time flier Jose Hernandez’ hometown of Stockton, Calif., has a small place in Discovery in the form of a lapel pin.

One of the flags aboard Discovery comes from the Hispanic Engineer National Achievement Awards Conference, which named veteran astronaut Danny Olivas its most promising engineer.

Sweden’s Christer Fuglesang has included numerous items from his native country, including a wooden chess piece.

There also are scores of items that NASA and other organizations included in the shuttle lockers. Like the items carried by the astronauts, the agency items will be prized upon their return.

Steven Siceloff
NASA's John F. Kennedy Space Center

For more information visit nasa.gov

From the Moon to Marine Measurements

A discovery about the moon made in the 1960s is helping researchers unlock secrets about Earth's ocean today.

By applying a method of calculating gravity that was first developed for the moon to data from NASA's Gravity Recovery and Climate Experiment, known as Grace, JPL researchers have found a way to measure the pressure at the bottom of the ocean. Just as knowing atmospheric pressure allows meteorologists to predict winds and weather patterns, measurements of ocean bottom pressure provide oceanographers with fundamental information about currents and global ocean circulation. They also hold clues to questions about sea level and climate. "Oceanographers have been measuring ocean bottom pressure for a long time, but the measurements have been limited to a few spots in a huge ocean for short periods of time," says JPL oceanographer Victor Zlotnicki.

Launched in 2002, the twin Grace satellites map Earth's gravity field from orbit 500 kilometers (310 miles) above the surface. They respond to how mass is distributed in the Earth and on Earth's surface -the greater the mass in a given area, the stronger the pull of gravity from that area.

The pressure at the bottom of the ocean is determined by the amount of mass above it. "Ocean bottom pressure is the sum of the weight of the whole atmosphere and the whole ocean," says Zlotnicki. "When winds move water on the surface, ocean bottom pressure changes. When glaciers melt and add water to the ocean, the ocean's mass increases and bottom pressure increases, either at one place or globally."

Launched in 2002, the twin Grace satellites map Earth's gravity field from orbit 500 kilometers (310 miles) above the surface. They respond to how mass is distributed in the Earth and on Earth's surface -the greater the mass in a given area, the stronger the pull of gravity from that area.

"Measuring ocean bottom pressure was one of the things we said we wanted to do from the very beginning of the mission," says Grace project scientist Michael Watkins, "but it has been a challenge. The signal is very small and hard to detect."

Gravity changes over the ocean are miniscule compared to those over land. The ocean is a fluid. It yields to pressure and spreads the effect over a vast area. Nothing in the ocean gives as big a gravity signal as a flooding Amazon River or melting glaciers in Greenland or Alaska, changes that Grace can measure fairly easily, says Watkins. "Those hydrology signals are huge in comparison," he says.

However, as the mission progressed, Watkins explains, the science team has found better ways to process Grace data. And by turning to a technique developed for the lunar world, Grace researchers are getting the precise measurements of ocean bottom pressure they were hoping for.

From the moon to the ocean bottom

In the days leading up to the Apollo missions, JPL scientists discovered that certain areas of the moon had higher concentrations of mass than others. The result of these "mass concentrations" was marked differences in the moon's gravity field. The researchers then devised a new way to calculate the gravity field called a "mascon" (for mass concentration) solution. Mascon solutions break the gravity field into small, individual regions. The more traditional ways of computing gravity, often called harmonic solutions, smooth everything together and calculate gravity for a whole large area or body.

This map shows changes in ocean bottom pressure measured by NASA's Gravity Recovery and Climate Experiment (Grace). Red shows where pressure varies by large amounts, blue where it changes very little.

Recently scientists have begun developing mascon solutions for Grace data for use in a variety of studies, and they are revealing fascinating new details about Earth's gravity field. These mascon solutions are also proving to be a key to Grace's ability to measure ocean bottom pressure.

"Some of the very best harmonic solutions show some bottom pressure signals, but the mascon solutions appear to do a better job and provide much higher resolution," says Watkins. "Using a mascon solution with Grace data is a way of weighing each little piece of the ocean," he says. The result is a new view of the gravity field - one that reveals sharp contrasts in gravity precise enough to calculate variations in ocean bottom pressure.

A large field experiment off the coast of Japan provided an unusual and welcomed opportunity to put Grace mascon estimates of ocean bottom pressure to the test. There are few places in the ocean where there are enough data on ocean bottom pressure to validate the satellite's observations.

Oceanographer Jae-Hun Park and his colleagues at the University of Rhode Island compared the Grace measurements with data collected by a large array of pressure-reading instruments stationed on the ocean bottom as part of the Kuroshio Extension System Study. This two-year observational program to study deep ocean currents and fronts ran from 2004 to 2006.

"Our site covered a very wide area of 600 by 600 kilometers (370 miles) with 43 available bottom pressure sensors," says Park. He and his colleagues found that while some of the individual sensors had very high correlations with Grace measurements, others were very low. "These low correlations were small-scale eddies that Grace cannot catch," explains Park. Grace's resolution is about 200 kilometers (125 miles).

However, when they compared the spatially averaged monthly mean ocean bottom pressure measured by the ocean sensors with the latest JPL Grace mascon solution for the center of the array, "we found a high correlation between the Grace measurements and our in-situ measurements," says Park. "This experiment gave us the opportunity to validate the Grace data." The results of the study appeared last year in Geophysical Research Letters.

Astronaut Edwin E. Aldrin Jr., lunar module pilot of the first lunar landing mission, poses for a photograph beside the deployed United States flag during an Apollo 11 extravehicular activity (EVA) on the lunar surface on July 20, 1969.

Grace's new ability to detect small changes in ocean mass - reflected in ocean bottom pressure - will help scientists answer ongoing questions about sea level and climate change. It will help clarify, for example, just how much of sea level change is due to differences in ocean mass, the result of evaporation, precipitation, melting land ice, or river run-off and how much is due to temperature and salinity.

"Now, for the first time with these new mascon solutions," say Zlotnicki, "Grace will allow us to measure changes in ocean bottom pressure globally for long periods of time. This is a new tool for oceanography."

NASA Global Climate Change NASA/Jet Propulsion Laboratory

For more information visit nasa.gov

'Calypso' Panorama of Spirit's View from 'Troy' (Stereo)

This full-circle, stereo view from the panoramic camera (Pancam) on NASA's Mars Exploration Rover Spirit shows the terrain surrounding the location called "Troy," where Spirit became embedded in soft soil during the spring of 2009. The view combines a stereo pair so that it appears three-dimensional when seen through red-blue glasses, with the red lens on the left.

The Pancam team named this scene the camera's Calypso Panorama. The hundreds of images combined into this view were taken beginning on the 1,906th Martian day (or sol) of Spirit's mission on Mars (May 14, 2009) and ending on Sol 1943 (June 20, 2009).

Spirit has been investigating a region within Mars' Gusev Crater for more than 67 months in what was originally planned as a three-month mission.

Image Credit: NASA/JPL-Caltech/Cornell University
› Full resolution jpeg (28 Mb)

For more information visit nasa.gov

'Calypso' Panorama of Spirit's View from 'Troy'

This full-circle view from the panoramic camera (Pancam) on NASA's Mars Exploration Rover Spirit shows the terrain surrounding the location called "Troy," where Spirit became embedded in soft soil during the spring of 2009. The hundreds of images combined into this view were taken beginning on the 1,906th Martian day (or sol) of Spirit's mission on Mars (May 14, 2009) and ending on Sol 1943 (June 20, 2009).

North is at the center; south at both ends. The western edge of the low plateau called Home Plate dominates the right half of the panorama. At the far right is a bright-topped mound called "Von Braun," a possible future destination for Spirit's exploration. Near the center of the panorama, in the distance, lies Husband Hill, where Spirit recorded views from the summit in 2005. The ridge on the left, near the rover tracks leading to Troy from the north, is called "Tsiolkovsky." For scale, the parallel tracks are about 1 meter (39 inches) apart. The track on the right is more evident because Spirit was driving backwards, dragging its right-front wheel, which no longer rotates.

The bright soil in the center foreground is soft material in which Spirit became embedded after the wheels on that side cut through a darker top layer. The composition of different layers in the soil at the site became the subject of intense investigation by tools on Spirit's robotic arm.

The Pancam team named this scene the camera's Calypso Panorama. This version is an approximate true-color, red-green-blue composite panorama generated from images taken through the Pancam's 750-nanometer, 530-nanometer and 480-nanometer filters. This "natural color" view is the rover team's best estimate of what the scene would look like if we were there and able to see it with our own eyes.

Spirit has been investigating a region within Mars' Gusev Crater for more than 67 months in what was originally planned as a three-month mission.

Image Credit: NASA/JPL-Caltech/Cornell University

› Full resolution jpeg (28 Mb)

For more information visit nasa.gov

Mars Orbiter Puts Itself in Safe Mode Again

Mars Reconnaissance Orbiter Mission Status Report

PASADENA, Calif. - NASA's Mars Reconnaissance Orbiter put itself into a safe mode Wednesday morning, Aug. 26, for the fourth time this year, while maintaining spacecraft health and communications. While in safe mode, the spacecraft has limited activities pending further instructions from ground controllers.

Engineers have begun the process of diagnosing the problem prior to restoring the orbiter to normal science operations, a process expected to take several days. They will watch for engineering data from the spacecraft that might aid in identifying the cause of event and possibly of previous ones. The orbiter spontaneously rebooted its computer Wednesday, as it did in February and June, but did not switch to a redundant computer, as it did in early August.

Artist's concept of the Mars Reconnaissance Orbiter. Image credit: NASA/JPL

To help in investigating a root cause of the three previous anomalies, engineers had programmed the spacecraft to frequently record engineering data onto non-volatile memory. That could give an improved record of spacecraft events leading up to the reboot.

"We hope to gain a better understanding of what is triggering these events and then have the spacecraft safely resume its study of Mars by next week," said Mars Reconnaissance Orbiter Project Manager Jim Erickson of NASA's Jet Propulsion Laboratory, Pasadena, Calif.

The spacecraft has been investigating Mars with six science instruments since it reached that planet in 2006. It has returned more data than all other current and past Mars missions combined.

Media contacts: Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278
guy.webster@jpl.nasa.gov

For more information visit nasa.gov

'Calypso' Panorama of Spirit's View from 'Troy' (False Color)

This full-circle view from the panoramic camera (Pancam) on NASA's Mars Exploration Rover Spirit shows the terrain surrounding the location called "Troy," where Spirit became embedded in soft soil during the spring of 2009. The hundreds of images combined into this view were taken beginning on the 1,906th Martian day (or sol) of Spirit's mission on Mars (May 14, 2009) and ending on Sol 1943 (June 20, 2009).

North is at the center; south at both ends. The western edge of the low plateau called Home Plate dominates the right half of the panorama. At the far right is a bright-topped mound called "Von Braun," a possible future destination for Spirit's exploration. Near the center of the panorama, in the distance, lies Husband Hill, where Spirit recorded views from the summit in 2005. The ridge on the left, near the rover tracks leading to Troy from the north, is called "Tsiolkovsky." For scale, the parallel tracks are about 1 meter (39 inches) apart. The track on the right is more evident because Spirit was driving backwards, dragging its right-front wheel, which no longer rotates.

The bright soil in the center foreground is soft material in which Spirit became embedded after the wheels on that side cut through a darker top layer. The composition of different layers in the soil at the site became the subject of intense investigation by tools on Spirit's robotic arm.

The Pancam team named this scene the camera's Calypso Panorama. This version is a false-color, red-green-blue composite panorama generated from images taken through the Pancam's 750-nanometer, 530-nanometer and 430-nanometer filters. The false color enhances visibility of differences among the types of rock and soil material in the image.

Spirit has been investigating a region within Mars' Gusev Crater for more than 67 months in what was originally planned as a three-month mission.

Image Credit: NASA/JPL-Caltech/Cornell University
› Full resolution jpeg (20 Mb)

For more information visit nasa.gov

Hummocks, Blocks, and Craters

The farside crater Tsiolkovskiy is one of the most spectacular and unique geologic features on the Moon. Identified in the first image of the farside, and named after visionary space pioneer Konstantin Tsiolkovskiy, Tsiolkovskiy (185 km diameter) has a an irregular (non-circular) shape, a central peak, and is incompletely filled with mare basalt. Many geological and geomorphological features can be seen within and around the crater, making this a particularly interesting place on the Moon to work and study!

Two side-by-side LROC images provide an crisp and detailed view (about 0.8 m/pixel) of the crater rim and its ejecta blanket bringing to bear impact cratering as the dominant geologic process in the inner Solar System. Although you are looking at the ejecta blanket of a large lunar crater, this surface is also covered with both smaller and younger impact craters as well as multiple generations of features influenced by impact cratering. Details such as individual boulders, boulder trails, hummocks, and possibly small outcrops can be readily identified. Outcrops are the holy grail of lunar geology - rock that is still in place from the time it was formed. The Apollo astronauts probably only saw outcrop at one landing site, Apollo 15. Watch the movies formed from this mosaic: in places you will see rocky areas that may indicate outcrop. However, these are probably only large coherent blocks of material thrown out during the Tsiolkovskiy event (or some other impact). Such questions can best be investigated by astronauts living and working on the Moon. LROC is showing that everywhere you look on the Moon there are fascinating and enigmatic features awaiting our return!

Credit: NASA/GSFC/Arizona State University

For more information visit nasa.gov

Map Characterizes Active Lakes Below Antarctic Ice

Lakes in Antarctica, concealed under miles of ice, require scientists to come up with creative ways to identify and analyze these hidden features. Now, researchers using space-based lasers on a NASA satellite have created the most comprehensive inventory of lakes that actively drain or fill under Antarctica's ice. They have revealed a continental plumbing system that is more dynamic than scientists thought.

"Even though Antarctica's ice sheet looks static, the more we watch it, the more we see there is activity going on there all the time," said Benjamin Smith of the University of Washington in Seattle, who led the study.

Dots represent the locations where scientists have identified 124 active lakes below the ice sheet in Antarctica. Warmer colors (orange and red) depict lakes with larger water volumes while cooler colors (green and blue) depict lakes with smaller volumes. Purple areas show the locations of previously known inactive lakes. Credit: Ben Smith, University of Washington

Unlike most lakes, Antarctic lakes are under pressure from the ice above. That pressure can push melt water from place to place like water in a squeezed balloon. The water moves under the ice in a broad, thin layer, but also through a linked cavity system. This flow can resupply other lakes near and far.

Understanding this plumbing is important, as it can lubricate glacier flow and send the ice speeding toward the ocean, where it can melt and contribute to sea level change. But figuring out what's happening beneath miles of ice is a challenge.

Researchers led by Smith analyzed 4.5 years of ice elevation data from NASA's Ice, Cloud and land Elevation satellite (ICESat) to create the most complete inventory to date of changes in the Antarctic plumbing system. The team has mapped the location of 124 active lakes, estimated how fast they drain or fill, and described the implications for lake and ice-sheet dynamics in the Journal of Glaciology.

What Lies Beneath

For decades, researchers flew ice-penetrating radar on airplanes to "see" below the ice and infer the presence of lakes. In the 1990s, researchers began to combine airborne- and satellite-based data to observe lake locations on a continent-wide scale.

Scientists have since established the existence of about 280 "subglacial" lakes, most located below the East Antarctic ice sheet. But those measurements were a snapshot in time, and the question remained as to whether lakes are static or dynamic features. Were they simply sitting there collecting water?

In 2006 Helen Fricker, a geophysicist at the Scripps Institution of Oceanography, La Jolla, Calif., used satellite data to first observe subglacial lakes on the move. Working on a project to map the outline of Antarctica's land mass, Fricker needed to differentiate floating ice from grounded ice. This time it was laser technology that was up to the task. Fricker used ICESat's Geoscience Laser Altimeter System and measured how long it took a pulse of laser light to bounce of the ice and return to the satellite, from which she could infer ice elevation. Repeating the measurement over a course of time revealed elevation changes.

Fricker noticed, however, a sudden dramatic elevation change -- over land. It turned out this elevation change was caused by the filling and draining of some of Antarctica's biggest lakes.

"Sub-ice-sheet hydrology is a whole new field that opened up through the discovery of lakes filling and draining on relatively short timescales and involving large volumes of water," said Robert Bindschadler, a glaciologist at NASA's Goddard Space Flight Center in Greenbelt, Md., who has used ICESat data in other studies of Antarctica. "ICESat gets the credit for enabling that discovery."

Networking in the Antarctic

But were active lakes under the ice a common occurrence or a fluke?

To find out, Ben Smith, Fricker and colleagues extended their elevation analysis to cover most of the Antarctic continent and 4.5 years of data from ICESat's Geoscience Laser Altimeter System (GLAS). By observing how ice sheet elevation changed between the two or three times the satellite flew over a section every year, researchers could determine which lakes were active. They also used the elevation changes and the properties of water and ice to estimate the volume change.

Only a few of the more than 200 previously identified lakes were confirmed active, implying that lakes in East Antarctica's high-density "Lakes District" are mostly inactive and do not contribute much to ice sheet changes.

Most of the 124 newly observed active lakes turned up in coastal areas, at the head of large drainage systems, which have the largest potential to contribute to sea level change.

For some Antarctic lakes, pressure exerted by the ice above forces its water to fill an adjacent lake. The movement results in elevation changes at the surface over both lakes, detectable by NASA satellites. Credit: NASA Goddard's Scientific Visualization Studio › View conceptual animation

"The survey identified quite a few more subglacial lakes, but the locations are the intriguing part," Bindschadler said. "The survey shows that most active subglacial lakes are located where the ice is moving fast, which implies a relationship."

Connections between lakes are apparent when one lake drains and another simultaneously fills. Some lakes were found to be connected to nearby lakes, likely through a network of subglacial tunnels. Others appeared to be linked to lakes hundreds of miles away.

The team found that the rate at which lake water drains and fills varies widely. Some lakes drained or filled for periods of three to four years in steady, rather than episodic, changes. But water flow rates beneath the ice sheet can also be as fast as small rivers and can rapidly supply a lubricating film beneath fast-flowing glaciers.

"Most places we looked show something happening on short timescales," Smith said. "It turns out that those are fairly typical examples of things that go on under the ice sheet and are happening all the time all over Antarctica."

Related Links

› An inventory of active subglacial lakes in Antarctica detected by ICESat, 2003-2008 (pdf)
› Something Under the Ice is Moving
› Newly Discovered Antarctic Lakes, Feb. 4, 2006
› Lakes Drain under Antarctic Ice Sheet, April 24, 2007
› Subglacial Lakes, Antarctica, April 27, 2007
› Antarctica's Land and Ice Elevation

Kathryn Hansen
NASA Earth Science News Team

For more information visit nasa.gov

NASA's STS-128 Launch Blog

Join us here as we count down the final hours before space shuttle Discovery and the STS-128 crew lift off from NASA's Kennedy Space Center in Florida on this mission to the International Space Station. Launch is scheduled for 1:36 a.m. EDT on Tuesday.

From our blog console at Kennedy's Launch Control Center, we'll take you inside the countdown as launch time approaches.

NOTE: All times are posted in Eastern.

• Weather Update
  Tue, 25 Aug 2009 09:42:18 AM GMT+0530
  Range Weather has declared conditions are "red" for violations of the lightning rule and field mill rule in addition to the anvil cloud, cumulus cloud and flight-through-precipitation rules cited earlier. Also, in Houston, the Spaceflight Meteorology Group is tracking weather for the return-to-launch-site abort scenario that requires favorable weather at Kennedy. Return-to-launch-site weather currently is "no-go" due to rain within 20 nautical miles. They're also evaluating weather at the overseas emergency landing sites. There is observed precipitation at the Zaragoza landing site, but the Moron and Istres sites remain "go."

• Lightning Warning Issued
  Tue, 25 Aug 2009 09:25:24 AM GMT+0530
  A "Phase 2" lightning warning has been issued for Launch Pad 39A, Vehicle Assembly Building and other areas around the launch site due to a storm cell that appeared a while ago above the pad. The forecast remains 60 percent no-go. Meanwhile, the Closeout Crew continues to prepare for launch. The hatch is closed and sealed for flight and the team members are finishing up their work in the White Room.

• Lightning Strikes Near Launch Pad 39A
  Tue, 25 Aug 2009 09:14:59 AM GMT+0530
  There's been a lightning strike six miles east of Launch Pad 39A, where space shuttle Discovery and a crew of seven astronauts are awaiting launch at 1:36 a.m. tomorrow, less than two hours from now. Due to the lightning, the range now is "red" on three constraints: lightning, cumulus clouds and flight-through-precipitation.

• Hatch Latched for Flight; Leak Checks Begins
  Tue, 25 Aug 2009 09:10:46 AM GMT+0530
  The Closeout Crew closed and latched space shuttle Discovery's crew access hatch and is moving on to cabin leak checks. The technicians also will seal the hatch for flight by installing a carrier panel, a custom-fit sheet of aluminum covered with tiles for thermal protection.

• Hatch Closed; Weather Now 60 Percent "No-Go"
  Tue, 25 Aug 2009 09:07:05 AM GMT+0530
  Inside the White Room at Launch Pad 39A, members of the Closeout Crew have closed Discovery's crew hatch. Meanwhile, the weather situation continues its negative trend, with Shuttle Weather Officer alerting Launch Director Pete Nickolenko that the forecast right now calls for a 60 percent chance of weather preventing launch tonight. There are two hours left until launch time at 1:36:04 a.m., and weather and launch officials will keep monitoring the situation closely.

• Weather Update
  Tue, 25 Aug 2009 08:55:59 AM GMT+0530
  The favorable weather pattern expected this evening is not coming to fruition. Instead of clearing out, storm cells keep popping up, including one right over the launch pad. The weather situation is being closely monitored, and we'll bring you the latest as we hear it.

• Weather Update
  Tue, 25 Aug 2009 08:41:43 AM GMT+0530
  Shuttle Weather Officer Kathy Winters has informed Launch Director Pete Nickolenko that the Eastern Range has gone "red," or "no-go," due to a new system forming over the launch pad. Specifically, the new weather system violates the cumulus-cloud rule and flight-through-precipitation rule. Weather officials with the 45th Weather Squadron and the Spaceflight Meteorology Group in Houston continue to keep a close eye on the weather around the launch and landing sites at NASA's Kennedy Space Center in Florida, as well as emergency landing sites overseas should they be necessary.

• Comm Checks and Cabin Closeout Under Way
  Tue, 25 Aug 2009 08:38:27 AM GMT+0530
  The next step for the crew is to complete a round of communications checks and air-to-ground voice checks between the astronauts, Launch Control Center at Kennedy and Mission Control Center at NASA's Johnson Space Center in Houston. Meanwhile, the Closeout Crew will remove all non-flight items and finish up any additional work inside Discovery's crew module before closing the hatch.

• With Hernandez Seated, Boarding is Complete
  Tue, 25 Aug 2009 08:31:54 AM GMT+0530
  Last to board Discovery is Mission Specialist Jose Hernandez, another first-time shuttle flier. Strapped into Seat 5, he'll sit behind the commander on the left-rear side of the flight deck. Hernandez is the first NASA astronaut to offer a bilingual Twitter account, with "tweets" in both English and Spanish.
  
  Three hours ago, he tweeted in English, "Folks this is my last tweet before I go into space! Will start to suit up in 30 minutes, listen to weather brief and head to the pad!" He followed with the same message in Spanish: "Mi ultimo tweet antes de ir al espacio! En media hora me visto, escucharemos el status del clima y rumbo a la plataforma de lanzamiento!"
  
  To read more of Hernandez's insights and updates, go to twitter.com/Astro_Jose. Now, back to the Launch Blog.
  

• Forrester Straps into Seat 3
  Tue, 25 Aug 2009 08:18:59 AM GMT+0530
  Mission Specialist Patrick Forrester also is seated inside Discovery at this point. Forrester, a retired U.S. Army colonel, will ride into orbit in Seat 3 on the second row of the flight deck. Forrester flew previously on STS-117 along with Sturckow and Olivas.

• Olivas and Fuglesang Take Their Seats
  Tue, 25 Aug 2009 08:16:50 AM GMT+0530
  Down on Discovery's middeck, Mission Specialist Danny Olivas is strapped into Seat 5, on the left side nearest the hatch. Mission Specialist Christer Fuglesang is climbing into the center of the middeck, Seat 6. A member of the European Space Agency's astronaut corps from Sweden, Fuglesang flew aboard Discovery once before on mission STS-116.

• Ford Climbs Aboard

Tue, 25 Aug 2009 07:57:59 AM GMT+0530Pilot Kevin Ford is climbing into Discovery's crew module. The pilot sits beside the commander in Seat 2, on the right side of the flight deck's front row. As a former colonel in the U.S. Air Force, he's racked up 4,300 flying hours in a variety of aircraft, but STS-128 will be his first spaceflight.
• Weather Update: Green on All Constraints
  Tue, 25 Aug 2009 07:56:50 AM GMT+0530
  Shuttle Weather Officer Kathy Winters just advised Launch Director Pete Nickolenko that weather is now "green," or favorable, on all constraints.

• Stott Next to Strap In
  Tue, 25 Aug 2009 07:50:31 AM GMT+0530
  Up next is rookie space flier Nicole Stott, who will serve as a mission specialist before transferring to the space station. Stott, a Florida native, is sitting on the right side of Discovery's middeck in Seat 7.

• Sturckow on Board
  Tue, 25 Aug 2009 07:48:30 AM GMT+0530
  First aboard Discovery is STS-128 Commander Rick Sturckow. He'll sit in Seat 1, the left-front seat of the flight deck. A colonel in the U.S. Marines, Sturckow has been an astronaut since 1994 and has flown in space three times before on shuttle missions STS-88, STS-105 and STS-117. All three were International Space Station missions.

• Astronauts Arrive at Launch Pad 39A
  Tue, 25 Aug 2009 07:36:11 AM GMT+0530
  It's time for the astronauts to start climbing aboard space shuttle Discovery. The White Room is only large enough to accommodate one or two astronauts at a time, in addition to the Closeout Crew. Before climbing through Discovery's side hatch, each astronaut is equipped with a parachute harness and a communications cap with a headset to wear under the helmet. The astronauts plug into cooling units and put on their gloves and helmets after strapping in.


STS-128 Blogger: Anna Heiney, public affairs web writer at NASA's Kennedy Space Center.

• Final Inspection Complete
  Tue, 25 Aug 2009 07:16:24 AM GMT+0530
  The Final Inspection Team has finished its survey of shuttle Discovery and Launch Pad 39A and is on its way back to the Launch Control Center to provide a report to launch management. Other than the previously reported ice formation spotted on the liquid hydrogen T-0 umbilical, the team members have not identified any other concerns. They will continue to monitor Discovery from a console in Firing Room 2.

• Discovery's Astronauts Leave for the Launch Pad
  Tue, 25 Aug 2009 07:16:06 AM GMT+0530
  The STS-128 astronauts are on their way to the launch pad, where their ride to orbit -- space shuttle Discovery -- is poised for liftoff. As they walked to the silver Astrovan, the crew smiled and waved to the enthusiastic crowd that always gathers to offer cheer and support. The drive to the launch pad is scheduled to take about 25 minutes. To avoid overheating in their heavy suits, the astronauts can plug into cooling units at each seat.
  
  The Astrovan, a modified vintage Airstream motor home, will make two stops along the way. First, Flight Crew Operations Director and astronaut Brent Jett will leave the van and climb into a waiting car that will take him to the Shuttle Landing Facility. The van will proceed to the Launch Control Center and drop off Vehicle Integration Test Team Chief Jerry Ross and other support personnel.

• T-3 Hours and Counting
  Tue, 25 Aug 2009 07:11:11 AM GMT+0530
  Countdown clocks are active once more, ticking toward liftoff of space shuttle Discovery at 1:36:05 a.m. Tuesday. The next built-in hold comes at T-20 minutes, when the clock will pause again for 10 minutes.
  Tonight's countdown continues to go very smoothly. Weather looks favorable at NASA's three transoceanic abort landing sites, or TAL sites, located at Zaragoza Air Base and Moron Air Base in Spain and Istres in France. There's a slight chance of showers at the prime landing site, Zaragoza; Moron and Istres both look good. NASA requires at least one of the TAL sites to be available in order to launch.
  We're standing by to see the astronauts leave their crew quarters behind and begin the drive out to the launch pad in the next few minutes.

• Ice Formation Spotted at Launch Pad 39A
  Tue, 25 Aug 2009 06:55:10 AM GMT+0530
  The Final Inspection Team is continuing its survey out at Launch Pad 39A. The inspection lasts about 2.5 hours and begins after the external fuel tank is loaded for flight. The team has reported an ice formation on the liquid hydrogen T-0 umbilical. Measuring about 4.5 inches long, 1.5 inches wide and one quarter of an inch in thickness, the ice is a milky color and bridges across from the umbilical to the orbiter. The team has seen this before during previous launch countdowns and this latest discovery is being assessed by launch managers.

• Weather 'Shaping Up Nicely'
  Tue, 25 Aug 2009 06:48:39 AM GMT+0530
  According to Lt. Colonel Patrick Barrett of the 45th Weather Squadron, the launch weather forecast continues to improve. Earlier, thunderstorms produced rain and lightning in various areas around the space center and just offshore. But the remaining storm cells are slowly dissipating, and the chance of favorable weather for liftoff remains at 80 percent -- good news for the STS-128 astronauts and the Kennedy launch team. "Right now, things are shaping up very nicely," Barrett said.

• Astronauts Suit Up for Liftoff
  Tue, 25 Aug 2009 06:41:46 AM GMT+0530
  Across Kennedy Space Center, in the historic suit-up room at crew quarters, the STS-128 astronauts are all smiles as suit technicians help them climb into their bright-orange, launch-and-entry suits. Officially, this pressurized suit is called the Advanced Crew Escape Suit, or ACES. It's worn during launches and landings because it provides breathing air and an array of survival tools.
  This is the last step for the crew to finish before heading out to Launch Pad 39A at 9:46 p.m.

• Final Inspection in Progress
  Tue, 25 Aug 2009 06:26:56 AM GMT+0530
  The Final Inspection Team is conducting a detailed survey of the space shuttle vehicle and launch pad structure. Also called the "Ice Team," the group's seven specialists began their inspection at the top of the pad's fixed service structure, and are working their way down to the surface of the mobile launcher platform. Using digital cameras, a telescope, an infrared radiometer and their own eyes, the Final Inspection Team looks for ice, frost or cracks forming on or near the shuttle's external tank.
  Darkness has settled across Kennedy Space Center. There are no technical issues being discussed by the launch control team, and the weather trend continues to improve. There are about 45 minutes left in the T-3-hour built-in hold.

• Closeout Crew Prepares for Astronauts' Arrival
  Tue, 25 Aug 2009 06:17:33 AM GMT+0530
  Inside the environmentally controlled White Room at the end of the orbiter access arm on Launch Pad 39A, the seven-person Closeout Crew is preparing for the astronauts' arrival and boarding later tonight. Astronaut Shane Kimbrough is providing his support, and as part of the Closeout Crew, he will help the flight crew strap into their seats inside Discovery's crew module.

• Meet the STS-128 Crew
  Tue, 25 Aug 2009 06:06:50 AM GMT+0530
  Of the seven astronauts on the STS-128 flight crew, four -- Commander Rick Sturckow and Mission Specialists Patrick Forrester, Danny Olivas and Christer Fuglesang -- have flown on the shuttle before. Pilot Kevin Ford and Mission Specialists Jose Hernandez and Nicole Stott are making their first spaceflights. Stott will join Expedition 20 as a flight engineer aboard the International Space Station, relieving astronaut Tim Kopra, who will return to Earth aboard Discovery.
  The astronauts woke up at 3 p.m. today and have had medical checks and a snack in the astronaut crew quarters, located several miles from the launch complex in Kennedy's Operations and Checkout Building. They'll receive a weather briefing shortly, then begin suiting up for launch.

• Discovery, STS-128 Crew Await Early-Morning Liftoff
  Tue, 25 Aug 2009 05:57:31 AM GMT+0530
  Good evening, and thanks for joining us for the countdown to launch of space shuttle Discovery on the STS-128 mission, the 30th flight to the International Space Station. Liftoff is set for 1:36 a.m. Tuesday from Launch Pad 39A at NASA's Kennedy Space Center in Florida. The Launch Blog comes to you from a console in Firing Room 3 at Kennedy's Launch Control Center, about three miles away from the launch pad.
  At T-3 hours and holding, all is well in the Launch Control Center, where members of the launch team are monitoring the countdown. Florida's dynamic summer weather is legendary, and although storms rolled through during the afternoon and early evening, the weather trend is improving according to Shuttle Weather Officer Kathy Winters. The launch forecast is holding with an 80 percent chance of favorable conditions at liftoff.
  Discovery's large external fuel tank was loaded earlier this evening with about 500,000 gallons of chilled liquid oxygen and liquid hydrogen. These propellants will feed the shuttle's three main engines as the vehicle speeds toward orbit. The tanking process began at 4:11 p.m. and finished at 7:14 p.m. Now in stable replenish, the tank will continue to be topped off until the final minutes of the countdown.
  It's going to be an exciting evening, so stay with us.

• Join us for Launch
  Sat, 22 Aug 2009 02:23:32 AM GMT+0530
  Our live coverage of the STS-128 countdown and launch begins Monday, Aug. 24 at 8:30 p.m. EDT. Please join us!

Live Coverage Team

Blog Updates: Anna Heiney
Site Updates: Steve Siceloff
Quality Control: Rebecca Sprague
Videos/Facebook: Cheryl Mansfield
Photo Gallery: Elaine Marconi
Video Production: Aly Lee
Video Capture/Editing: Chris Chamberland,
Michael Chambers and Gianni Woods

For more information visit nasa.gov

L-2 Update

NASA's mission management team has given the "go" to continue the launch countdown. They determined there are no issues that would prevent an on-time launch of space shuttle Discovery's STS-128 mission to the International Space Station on Tuesday, Aug. 25 at 1:36 a.m. EDT.

NASA's Management Team Chair, Mike Moses gave an update of the maintenance and repair projects performed preparing the shuttle for launch and said the only concern at this point was the possible inclement weather just before the external tank is fueled.

"I'm really pleased to report that launch countdown activities are proceeding nominally and we working no issues," said Launch Director Pete Nickolenko.

Nickolenko reported that there are four launch attempts available within five days from Aug. 25 through Aug. 30 and he was "96 percent certain" of being able to launch in this time frame.

The forecast for launch has improved to 80 percent for favorable weather at time of liftoff according to Shuttle Weather Officer Kathy Winters. There is a possibility that storms could form within 5 miles of Launch Pad 39A just before fueling of the external tank violating constraints but the sea breezes could move them out of the area in time.

Rollback of the rotating service structure that protects the shuttle before launch is planned for 5 a.m. Monday and fueling of the external tank is scheduled to begin at 4:11 p.m.

For more information visit nasa.gov

NASA Releases GOES-14 Satellite Video of Hurricane Bill

NASA has released a video of Hurricane Bill today from the GOES-14 satellite. The video was put together from a series of still frames taken by the satellite using both infrared and visible imagery and provides different views of Hurricane Bill on August 20.

Earlier this summer, NASA launched the latest Geostationary Operational Environmental Satellite, GOES-O. Recently operations have been turned over to the National Oceanic and Atmospheric Administration (NOAA) and the satellite was renamed GOES-14. The satellite is still being tested in orbit, and it captured video of Hurricane Bill on August 20, while it was on its way to Bermuda.

NASA and NOAA's newest weather satellite, GOES-14, has captured some fascinating views of Hurricane Bill. This is a collection of a few quick movies put together by the GOES-14 team. Credit: NASAOES Project

The spectacular video is a collection of a few quick movies put together by the GOES-14 team from the NASA GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md.

The video includes an impressive zoom-out, showing how big the hurricane is, relative to the hemisphere. Bill is a large hurricane, more than 1,200 kilometers (746 miles) across, and the storm’s partially cloud-filled eye is nearly 50 kilometers (31 miles) wide.

On August 20, the date of the movie, Hurricane Bill had sustained winds of 135 mph, making it a powerful Category 4 storm. At that time hurricane-force winds extended outward up to 80 miles from the center. On August 21, Bill's sustained winds were near 110 mph and hurricane force winds extended up to 115 miles.

For daily updates and new NASA satellite images on Hurricane Bill, visit NASA's Hurricane Web Page at http://www.nasa.gov/hurricane. For forecasts and advisories on Hurricane Bill, visit NOAA's National Hurricane Center page: http://www.nhc.noaa.gov/.

Text credit: Rob Gutro/NASA's Goddard Space Flight Center

For more information visit nasa.gov

STS-128's Official Countdown Under Way

The countdown for the launch of space shuttle Discovery’s STS-128 mission officially is under way. The count began on-time at 11 p.m. EDT at the T-43 hour mark.

Launch teams are not working any issues that would prevent Discovery’s scheduled launch Tuesday, Aug. 25 at 1:36 a.m. on its 13-day mission to the International Space Station.

Discovery’s seven astronauts have additional mission study time in their overnight schedule before they head into their sleep period at 7 a.m. Saturday. The crew is scheduled to wake up at 3 p.m.

Tune in for the next countdown status briefing on NASA TV on Saturday at 10 a.m.

For more information visit nasa.gov

NASA Researcher Nets First Measure of Africa's Coastal Forests

Impoverished fishermen along the coast of tropical African countries like Mozambique and Madagascar may have only a few more years to eke out a profit from one of their nations’ biggest agricultural exports. Within a few decades, they may no longer have a livelihood at all.

That's because swampy mangrove forests – essential breeding grounds for fish and shellfish in these countries – are being destroyed by worsening pollution, encroaching real estate development, and deforestation necessary to sustain large-scale commercial shrimp farming.

NASA researcher Lola Fatoyinbo (left), seen here in June 2005 on the site where she conducted some of her field measurements, stands among the large branches of a Rhizophora mucronata tree in a mangrove forest on Inhaca Island, Mozambique with one of her research assistants, a student from the University Eduardo Mondlane in Maputo, Mozambique. Credit: NASA/Temilola Fatoyinbo

The decline of these forests threatens much of Africa’s coastal food supply and economy. The destruction of mangroves - one of Earth’s richest natural resources – also has implications for everything from climate change to biodiversity to the quality of life on Earth. Growing up in Cotonou, Benin, environmental scientist Lola Fatoyinbo of NASA’s Jet Propulsion Laboratory (JPL) passed polluted mangroves daily. Inspired to help save the forests, she began a mission as a graduate student in the United States to gain more insight about African mangroves.

Her studies have brought her back to Africa, where she has journeyed along the coastlines to test a new satellite technique for measuring the area, height, and biomass of mangrove forests. She developed and employed a method that can be used across the continent, overcoming expensive, ad hoc, and inconsistent modes of ground-based measurement. Fatoyinbo’s approach recently produced what she believes is the first full assessment of the continent’s mangrove forests.

“We’ve lost more than 50 percent of the world’s mangrove forests in a little over half a century; a third of them have disappeared in the last 20 years alone," said Fatoyinbo, whose earlier study of Mozambique’s coastal forests laid the groundwork for the continent-wide study. "Hopefully this technique will offer scientists and officials a method of estimating change in this special type of forest.”

An Ecosystem Apart

Mangroves are the most common ecosystem in coastal areas of the tropics and sub-tropics. The swampy forests are essential - especially in densely-populated developing countries - for rice farming, fishing and aquaculture (freshwater and saltwater farming), timber, and firewood. Some governments also increasingly depend on them for eco-tourism.

The large, dense root systems are a natural obstacle that helps protect shorelines against debris and erosion. Mangroves are often the first line of defense against severe storms, tempering the impact of strong winds and floods.

Fatoyinbo used a remote sensing software-based classification method that separates the different types of land cover like forest, urban area, and soil, differentiating by colors or reflectance. Here, mangrove forest cover is shown in green along the coast of northern Cameroon on a Landsat-derived map (with ocean shown in blue and other land cover types in black). Credit: NASA/Temilola Fatoyinbo

These coastal woodlands also have a direct link to climate, sequestering carbon from the atmosphere at a rate of about 100 pounds per acre per day – comparable to the per acre intake by tropical rainforests (though rainforests cover more of Earth’s surface).

“To my knowledge, this study is the first complete mapping of Africa’s mangroves, a comprehensive, historic baseline enabling us to truly begin monitoring the welfare of these forests,” said Assaf Anyamba, a University of Maryland-Baltimore County expert on vegetation mapping, based at NASA’s Goddard Space Flight Center in Greenbelt, Md.

Climbing the Right Tree

Fatoyinbo’s research combines multiple satellite observations of tree height and land cover, mathematical formulas, and “ground-truthing” data from the field to measure the full expanse and makeup of the coastal forests.

Her measurements yielded three new kinds of maps of mangroves: continental maps of how much land the mangroves cover; a three-dimensional map of the height of forest canopies across the continent; and biomass maps that allow researchers to assess how much carbon the forests store.

“Beyond density or geographical size of the forests, the measurements get to the heart of the structure, or type, of mangroves," explained Fatoyinbo. "It’s that trait – forest type – that drives which forests land managers target for agriculture, conservation, and habitat suitability for animals and people.”

Fatoyinbo and colleague Marc Simard of JPL used satellite images from the NASA-built Landsat and a complex software-based color classification system to distinguish areas of coastal forests from other types of forests, urban areas or agricultural fields. They also integrated data from NASA’s Shuttle Radar Topography Mission (SRTM) to create relief maps of the height of the forest canopy. Finally, they merged the broad radar maps with high-accuracy observations from a light detection and ranging (commonly called lidar) instrument aboard NASA’s Ice, Cloud, and land Elevation Satellite (ICESat) to obtain accurate height estimates.

Fatoyinbo double-checked the accuracy of her satellite measurements at the ground level in the only way possible: She went to Africa to measure tree heights and trunk diameters in person. Using a hand-held instrument called a clinometer and a simple trigonometry formula, Fatoyinbo visited Mozambique, measured the trees, and found she indeed had very accurate measurements of the forests.

Preserving the Forest for the Trees

Mangroves are hardy and adaptable forests that can thrive under extreme heat, very high salt levels, and swampy soil. Rampant clearing for agriculture and construction, soil toxicity, and long-term oil and sewage pollution, however, are increasingly threatening their survival and more than 1,300 animal species in ways that nature cannot.

Fatoyinbo’s height map of Gabon’s mangrove forest canopy (left image) indicates heights ranging from 0 to 40 meters. In the right image, Fatoyinbo used Google Earth software to overlay the same three-dimensional height map of Gabon’s mangroves. Credit: NASA/Temilola Fatoyinbo

“The United States’ largest mangrove forests, Florida’s Everglades, are largely protected now and recognized as an endangered natural resource,” explained Fatoyinbo. “But in many other places, resource managers lack solid monitoring capabilities to counter mangrove exploitation. Better mangrove monitoring will, I hope, mean better management and preservation.”

Free satellite data can help ease the problems of money, logistics, and political instability that can prevent mangrove preservation. For that reason, Anyamba and Fatoyinbo are working to convince the United Nations Environment Program and the UN Educational, Scientific and Cultural Organization to include the study’s data in their environmental assessments.

The new technique also distinguishes itself, added Anyamba, “as an excellent example of how we can use different remote sensing technologies together to address science questions and global social issues.”

Related Links:

> Fatoyinbo’s original study on mangrove measurements in Mozambique, Journal of Geophysical Research
> More about NASA’s Lola Fatoyinbo
> Scientists Find Climate Change to Have Paradoxical Effects on Coastal Wetlands
> Rice Farming in Mangroves, Guinea-Bissau
> Mangroves Along Bombetoka Bay, Madagascar
> NASA’s Shuttle Radar Topography Mission
> NASA’s ICESat Mission

Gretchen Cook-Anderson
NASA Earth Science News Team

For more information visit nasa.gov

NASA And ISRO Satellites Perform In Tandem To Search For Ice On The Moon

WASHINGTON – On Aug. 20, 2009 NASA and the Indian Space Research Organization (ISRO) will attempt a novel joint experiment that could yield more information on whether ice exists in a permanently shadowed crater near the north pole of the moon. Currently the ISRO’s Chandrayaan-1 and NASA’s Lunar Reconnaissance Orbiter (LRO) spacecraft are orbiting the moon. While LRO is in its commissioning phase the two spacecraft pass close enough to each other when they are over the lunar north pole to attempt a unique experiment. Both spacecraft are equipped with a NASA Miniature Radio Frequency (RF) instrument that functions as a Synthetic Aperture Radar (SAR), known as Mini-SAR on Chandrayaan-1 and Mini-RF on LRO. The experiment uses both radars to point at Erlanger Crater at the same time.

Normally the Mini-RF Instrument sends radio pulses to the moon and precisely records the radio echoes that bounce straight back from the surface, along with their timing and frequency. From these data scientists can build images of the moon that not only show areas they otherwise couldn’t see, such as the permanently-shadowed areas near the lunar poles, but also contain information on the physical nature of the surface.

NASA/GSFC/Arizona State University - Image of the crater Erlanger (87 N, 28.6 E; 10 km diameter), the target crater for our Bi-Static observations. Mini-SAR images suggest unusual scattering properties of the crater interior compared with its exterior. LROC Narrow Angle Camera image.

For the Bi-Static experiment the Mini-SAR on Chandrayaan-1 performs its normal SAR imaging (transmitting and receiving) while the Mini-RF is set to receive only. The two instruments look at the same location from different angles. Comparing the signal that bounces straight back to Chandrayaan with the signal that bounces at a slight angle to LRO provides unique information about the surface.

Stewart Nozette, Mini-RF principal investigator from the Universities Space Research Association’s Lunar and Planetary Institute, said, “An extraordinary effort was made by the whole NASA team working with ISRO to make this happen”

While this coordination sounds easy, this experiment is extremely challenging because both spacecraft are traveling at about 1.6 km per second and will be looking at an area on the ground about 18 km across. Due to the extreme speeds and the small point of interest, NASA and ISRO need to obtain and share information about the location and pointing of both spacecraft. The Bi-Static experiment requires extensive tracking by ground stations of NASA’s Deep Space Network, the Applied Physics Laboratory, and ISRO.

Arecibo Radiotelescope Puerto Rico - Low resolution Earth-based radar image of the North Pole of the Moon, showing the position of the crater Erlanger (arrow). Radar image (70 cm wavelength).

Even with the considerable planning and coordination between the U.S. and India the two instrument beams may not overlap, or may miss the desired location. Even without hitting the exact location Scientists may still be able to use the Bi-Static information to further knowledge already received from both instruments.

“The international coordination and cooperation between the two agencies for this experiment is an excellent opportunity to demonstrate future cooperation between NASA and ISRO, “says Jason Crusan, program executive for the Mini-RF program, from NASA’s Space Operations Mission Directorate, Washington, D.C.

“In the last few years we have seen a renaissance in international interest and cooperation in the study of the moon” says Gordon Johnson, program executive for the LRO, from NASA’s Exploration Systems Mission Directorate, Washington, D.C. “As LRO completes its commissioning phase, we look forward to LRO’s contribution to this international effort.”

LRO was launched June 18, 2009. Its objectives are to scout for safe landing sites, locate potential resources, characterize the radiation environment, and demonstrate new technology. NASA’s Goddard Space Flight Center in Greenbelt, Md. built and manages the mission for NASA’S Exploration Systems Mission Directorate in Washington. LRO is a NASA mission with international participation from the Institute for Space Research in Moscow. Russia provides the neutron detector aboard the spacecraft.

ISRO/NASA/JHUAPL/LPI - Mosaic of Mini-SAR image strips of the north polar area, showing the crater Erlanger, just south of the crater Peary. North Pole is in the direction of left top, out of frame. Mini-SAR radar image, Chandrayaan-1 mission.

Instrument principal investigators Stewart Nozette (LRO) and Paul Spudis (Chandrayaan-1) are from the Universities Space Research Association’s Lunar and Planetary Institute. NASA’s Space Operations Mission Directorate, NASA Headquarters, manages the Mini-RF program. NASA’s Exploration Systems Mission Directorate, NASA Headquarters, manages the LRO.

In addition to Mini-SAR the Chandryaan-1 spacecraft, which was launched in October 2008 from India’s Satish Dhawan Space Centre, also carries NASA’s Moon Mineralogy Mapper for assessing the moon’s mineral resources.

For more information on the Lunar Reconnaissance Orbiter mission, visit: http://www.nasa.gov/lro and nasa.gov

Chandra's Top 10 Scientific Contributions

NASA's Chandra X-ray Observatory is celebrating 10 years of exploring the invisible universe. On Aug. 19, 1999, Chandra captured its first image as an astronomical observatory. This first light image opened a new era for science as Chandra began its mission to open a mysterious universe.

Chandra enables scientists from around the world to obtain unprecedented X-ray images of exotic environments to help understand the evolution of the cosmos. The observatory not only helps to probe these mysteries, but also serves as a unique tool to study detailed physics in a laboratory that cannot be replicated on Earth.

"Chandra has changed the whole understanding of dark matter and increased our knowledge of dark energy, as well as gathered new information on black holes," said Dr. Martin Weisskopf, Chandra project scientist at the Marshall Space Flight Center.

"Chandra has produced 10,000 observations in its 10-year life and the demand for observation time, by scientists, is five- to six-times what is available," said Chandra Program Manager Keith Hefner of the Marshall Center. "It continues to be an engineering marvel that has more than doubled its original five-year mission."

A Chandra "Top 10" reveals some of the most noteworthy discoveries:

1. Chandra finds a ring around the Crab Nebula. After only two months in space, the observatory reveals a brilliant ring around the heart of the Crab Pulsar in the Crab Nebula -- the remains of a stellar explosion -- providing clues about how the nebula is energized by a pulsing neutron, or collapsed star. (Sept. 28, 1999)

The Crab Nebula, seen by Chandra on September 28, 1999. Image credit: NASA/CXC/SAO

2. Chandra finds the most distant X-ray cluster. Using the Chandra Observatory, astronomers find the most distant X-ray cluster of galaxies yet. Approximately 10 billion light years from Earth, the cluster 3C294 is 40 percent farther than the next most distant X-ray galaxy cluster. (Feb. 15, 2001)
3. Chandra makes deepest X-ray exposure. A Chandra image, Deep Field North, captures for 23 days an area of the sky one-fifth the size of the full moon. Even though the faintest sources detected produced only one X-ray photon every four days, Chandra finds more than 600 X-ray sources, most of them super massive black holes in galaxy centers. (June 19, 2003)

Distant galaxy 3C294, observed by Chandra on February 15, 2001. Image credit: NASA/IoA/A.Fabian et al.

4. Chandra hears a black hole. Using the Chandra observatory, astronomers for the first time detected sound waves from a super massive black hole. Coming from a black hole 250 million light years from Earth, the "note" is the deepest ever detected from an object in the universe. (Sept. 9, 2003)
5. Chandra opens a new line of investigation on dark energy. Using galaxy-cluster images from Chandra, astronomers apply a powerful, new method for detecting and probing dark energy. The results offer intriguing clues about the nature of dark energy and the fate of the universe. (May 18, 2004).

Composite of galaxy cluster 1E 0657-56, a Chandra image from on August 21, 2006. Image credit: X-ray: NASA/CXC/CfA/M.Markevitch et al.; Optical: NASA/STScI; Magellan/U.Arizona/D.Clowe et al.; Lensing Map: NASA/STScI; ESO WFI; Magellan/U.Arizona/D.Clowe et al.

6.Chandra finds that Saturn reflects X-rays from the sun. The findings stem from the first observation of an X-ray flare reflected from Saturn's low-latitudes - the region that correlates to Earth's equator and tropics. (May 25, 2005)
7. Chandra finds proof of dark matter. In galaxy clusters, the normal matter, like the atoms that make up the stars, planets, and everything on Earth, is primarily in the form of hot gas and stars. The mass of the hot gas between the galaxies is far greater than the mass of the stars in all of the galaxies. This normal matter is bound in the cluster by the gravity of an even greater mass of dark matter. Without dark matter, which is invisible and can only be detected through its gravity, the fast-moving galaxies and the hot gas would quickly fly apart. (Aug. 21, 2006)
8. Chandra sees brightest supernova ever. The brightest stellar explosion ever recorded may be a long-sought new type of supernova, according to observations by NASA's Chandra X-ray Observatory and ground-based optical telescopes. This discovery indicates that violent explosions of extremely massive stars were relatively common in the early universe, and that a similar explosion may be ready to go off in our own galaxy. (May 7, 2007)

Artist concept of supernova SN 2006gy, viewed by Chandra on May 7, 2007. Illustration: NASA/CXC/M.Weiss

9. Chandra finds a new way to weigh black holes. By measuring a peak in the temperature of hot gas in the center of the giant elliptical galaxy NGC 4649, scientists have determined the mass of the galaxy's super massive black hole. The method, applied for the first time, gives results that are consistent with a traditional technique. (July 16, 2008)
10. Long observation from Chandra identified the source of this energy for blobs. The X-ray data show that a significant source of power within these colossal structures is from growing super massive black holes partially obscured by dense layers of dust and gas. The fireworks of star formation in galaxies are also seen to play an important role, thanks to Spitzer Space Telescope and ground-based observations. (June 24, 2009)

The Marshall Center manages the Chandra program for the Science and Mission Directorate, NASA Headquarters, Washington. Northrop Grumman of Redondo Beach, Calif., formerly TRW Inc., was the prime development contractor for the observatory. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass.

Janet Anderson, 256-544-6162
Marshall Space Flight Center, Huntsville, Ala.
Janet.L.Anderson@nasa.gov
For more information visit:

http://www.nasa.gov/chandra and nasa.gov