Digital Elevation Models of the Moon

Robotic exploration missions provide NASA vast amounts of data to prepare for future human exploration missions and learn more about the universe.

Objective: The U.S. Geological Survey (USGS) is working with NASA to make lunar maps. Digital elevation models (DEMs) will be used to map terrain, locate lunar resources and assess prospective landing sites.

Description: The USGS constructed this DEM of a 50x80 km area of the Aristarchus Plateau, including the “Cobra Head.” Using Apollo Panoramic Camera images, the elevation of each lunar feature is calculated to an accuracy of 0.75 to 1.2 m.

Timeframe: The new Lunar Mapping and Modeling Project (LMMP) Web site, available in late fall 2010, will build integrated data sets from the Lunar Reconnaissance Orbiter (LRO), and other lunar missions over the next two years. The USGS generated maps will be available on that Web site.

Application: An integrated, easy-to-use Web site allows easy access to current lunar data and can be used by any scientist, student or lunar explorer.

For more information visit http://www.nasa.gov/exploration/multimedia/highlights/2010-09B.html

The Lunar Far Side as Seen by the Lunar Orbiter Laser Altimeter

Topography data from the Lunar Orbiter Laser Altimeter (LOLA) aboard the Lunar Reconnaissance Orbiter reveal a violent impact history on the far side of the Moon. Scientists are using LOLA data to identify and map the distribution of impact craters and basins on the lunar surface, which in turn reveals information about the age of the lunar crust and early bombardment of the Solar System.

Credit: NASA/Goddard Space Flight Center

For more information visit http://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/lola-20100312-farside.html

LCROSS Impact Data Indicates Water on Moon

The argument that the moon is a dry, desolate place no longer holds water.

Secrets the moon has been holding, for perhaps billions of years, are now being revealed to the delight of scientists and space enthusiasts alike.

NASA today opened a new chapter in our understanding of the moon. Preliminary data from the Lunar CRater Observation and Sensing Satellite, or LCROSS, indicates that the mission successfully uncovered water during the Oct. 9, 2009 impacts into the permanently shadowed region of Cabeus cater near the moon’s south pole.

The impact created by the LCROSS Centaur upper stage rocket created a two-part plume of material from the bottom of the crater. The first part was a high angle plume of vapor and fine dust and the second a lower angle ejecta curtain of heavier material. This material has not seen sunlight in billions of years.

The visible camera image showing the ejecta plume at about 20 seconds after impact. Credit: NASA

"We're unlocking the mysteries of our nearest neighbor and by extension the solar system. It turns out the moon harbors many secrets, and LCROSS has added a new layer to our understanding," said Michael Wargo, chief lunar scientist at NASA Headquarters in Washington.

Scientists have long speculated about the source of vast quantities of hydrogen that have been observed at the lunar poles. The LCROSS findings are shedding new light on the question of water, which could be more widespread and in greater quantity than previously suspected.

Permanently shadowed regions could hold a key to the history and evolution of the solar system, much as an ice core sample taken on Earth reveals ancient data. In addition, water, and other compounds represent potential resources that could sustain future lunar exploration.

Since the impacts, the LCROSS science team has been working almost nonstop analyzing the huge amount of data the spacecraft collected. The team concentrated on data from the satellite's spectrometers, which provide the most definitive information about the presence of water. A spectrometer examines light emitted or absorbed by materials that helps identify their composition.

Data from the down-looking near-infrared spectrometer. The red curve shows how the spectra would look for a "grey" or "colorless" warm (230 C) dust cloud. The yellow areas indicate the water absorption bands. Credit: NASA

"We are ecstatic," said Anthony Colaprete, LCROSS project scientist and principal investigator at NASA's Ames Research Center in Moffett Field, Calif. "Multiple lines of evidence show water was present in both the high angle vapor plume and the ejecta curtain created by the LCROSS Centaur impact. The concentration and distribution of water and other substances requires further analysis, but it is safe to say Cabeus holds water."

The team took the known near infrared spectral signatures of water and other materials and compared them to the spectra collected by the LCROSS near infrared spectrometer of the impact.

"We were only able to match the spectra from LCROSS data when we inserted the spectra for water," said Colaprete. "No other reasonable combination of other compounds that we tried matched the observations. The possibility of contamination from the Centaur also was ruled out."

Additional confirmation came from an emission in the ultraviolet spectrum that was attributed to hydroxyl, one product from the break-up of water by sunlight. When atoms and molecules are excited, they release energy at specific wavelengths that are detected by the spectrometers. A similar process is used in neon signs. When electrified, a specific gas will produce a distinct color. The ultraviolet visible spectrometer detected hydroxyl signatures just after impact that are consistent with a water vapor cloud in sunlight.

The visible camera image showing the ejecta plume at about 20 seconds after impact.Credit: NASA

Data from the other LCROSS instruments are being analyzed for additional clues about the state and distribution of the material at the impact site. The LCROSS science team along with colleagues are poring over the data to understand the entire impact event, from flash to crater, with the final goal being the understanding of the distribution of materials, and in particular volatiles, within the soil at the impact site.

"The full understanding of the LCROSS data may take some time. The data is that rich," said Colaprete. "Along with the water in Cabeus, there are hints of other intriguing substances. The permanently shadowed regions of the moon are truly cold traps, collecting and preserving material over billions of years."

LCROSS was launched June 18, 2009 as a companion mission to the Lunar Reconnaissance Orbiter, or LRO, from NASA's Kennedy Space Center in Florida. After separating from LRO, the LCROSS spacecraft held onto the spent Centaur upper stage rocket of the launch vehicle, executed a lunar swingby and entered into a series of long looping orbits around the Earth.

After traveling approximately 113 days and nearly 5.6 million miles (9 million km), the Centaur and LCROSS separated on final approach to the moon. Traveling as fast as a speeding bullet, the Centaur impacted the lunar surface shortly after 4:31 a.m. PDT Oct. 9 with LCROSS watching with its onboard instruments. Approximately four minutes of data was collected before the LCROSS itself impacted the lunar surface.

Working closely with scientists from LRO and other observatories that viewed the impact, the LCROSS team is working to understand the full scope of the LCROSS data. LRO continues to make passes over the impact site to give the LCROSS team additional insight into the mechanics of the impact and its resulting craters.

What other secrets will the moon reveal? The analysis continues!

Jonas Dino
NASA Ames Research Center

For more information visit http://www.nasa.gov/mission_pages/station/science/hico_raids.html

NASA Moon Mission Wins Second-Best of 'What's New' Award by Popular Science

The Lunar Reconnaissance Orbiter (LRO) is cited as one of the best innovations in aviation in the December issue of Popular Science.

"It is an honor to be selected by Popular Science for Best of What’s New in aviation," said Craig Tooley, LRO project manager from NASA’s Goddard Space Flight Center in Greenbelt, Md. "There was tremendous excitement about the United States returning to the moon after many years. I believe our selection is a result of that excitement."

Each year, the editors of Popular Science review thousands of products in search of the top 100 tech innovations of the year; breakthrough products and technologies that represent a significant leap in their categories. The winners -- the Best of What's New -- are awarded inclusion in the much-anticipated December issue of Popular Science, the most widely read issue of the year since the debut of Best of What's New in 1987. Best of What's New awards are presented to 100 new products and technologies in 11 categories: Automotive, Aviation and Space, Computing, Engineering, Gadgets, Green Technology, Home Entertainment, Security, Home Technology, Personal Health and Recreation.

"For 22 years, Popular Science has honored the innovations that surprise and amaze us -- those that make a positive impact on our world today and challenge our views of what’s possible in the future." said Mark Jannot, editor-in-chief of Popular Science. "The Best of What’s New Award is the magazine’s top honor, and the 100 winners -- chosen from among thousands of entrants -- represent the highest level of achievement in their fields."

Artist concept of the Lunar Reconnaissance Orbiter. Credit: NASA

LRO launched from Kennedy Space Center, Fla. on June 18, 2009. Since that time the spacecraft has completed calibration and commissioning. LRO has already begun its detailed survey of the moon. First results from the mission included -- new looks at the Apollo landing sites; indications that permanently shadowed and nearby regions may harbor water and hydrogen; observations that large areas in the permanently shadowed regions are colder than Pluto; and detailed information on terrain roughness.

LRO is scheduled for a one year exploration mission in a polar orbit about 31 miles above the lunar surface. During the next year, LRO will produce a complete map of the lunar surface in unprecedented detail, search for resources and potential safe landing sites for human explorers and measure lunar temperatures and radiation levels.

NASA’s Goddard Space Flight Center built and manages the mission for the Exploration Systems Mission Directorate at NASA Headquarters in Washington. The Institute for Space Research, Moscow, provided the neutron detector aboard the spacecraft.

Nancy N. Jones
NASA's Goddard Space Flight Center

For more information visit http://www.nasa.gov/mission_pages/LRO/news/popular_science.html

LRO Gets Additional View of Apollo 11 Landing Site

As the Apollo 11 Lunar Module (LM) neared the surface, Neil Armstrong could see the designated landing area would have been in a rocky area near West Crater. He had to change the flight plan and fly the LM westward to find a safe landing spot. This image is 742 meters wide (about 0.46 miles). North is towards the top of the image. Credit: NASA/GSFC/Arizona State University

With those eight words, astronaut Neil Armstrong let the world know that Apollo 11 had landed safely on the moon, beginning humankind's first exploration of another world. The landing certainly kept the mission operations crew in suspense as Armstrong maneuvered around the bouldery ejecta on the northeast flank of West Crater, finally settling down almost a kilometer to the west with only tens of seconds of fuel remaining.

Enlargement of area surrounding Apollo 11 landing site. Credit: NASA/GSFC/Arizona State University

"Houston, Tranquility Base here. The Eagle has landed."

The Lunar Reconnaissance Orbiter Camera team earlier released two pictures of the Apollo 11 landing site, each taken under different lighting conditions and at lower resolution than this image. This is LROC's first picture of Apollo 11 after LRO dropped into its 50 km mapping orbit. At this altitude, very small details of Tranquility Base can be discerned. The footpads of the LM are clearly discernible. Components of the Early Apollo Science Experiments Package (EASEP) are easily seen, as well. Boulders from West Crater lying on the surface to the east stand out, and the many small craters that cover the moon are visible to the southeast.

For more information visit http://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/lroc_200911109_apollo11.html

NASA Spacecraft Impacts Lunar Crater in Search for Water Ice

MOFFETT FIELD, Calif. -- NASA's Lunar Crater Observation and Sensing Satellite, or LCROSS, created twin impacts on the moon's surface early Friday in a search for water ice. Scientists will analyze data from the spacecraft's instruments to assess whether water ice is present.

The satellite traveled 5.6 million miles during an historic 113-day mission that ended in the Cabeus crater, a permanently shadowed region near the moon's south pole. The spacecraft was launched June 18 as a companion mission to the Lunar Reconnaissance Orbiter from NASA's Kennedy Space Center in Florida.

"The LCROSS science instruments worked exceedingly well and returned a wealth of data that will greatly improve our understanding of our closest celestial neighbor," said Anthony Colaprete, LCROSS principal investigator and project scientist at NASA's Ames Research Center in Moffett Field, Calif. "The team is excited to dive into data."

In preparation for impact, LCROSS and its spent Centaur upper stage rocket separated about 54,000 miles above the surface of the moon on Thursday at approximately 6:50 p.m. PDT.

Moving at a speed of more than 1.5 miles per second, the Centaur hit the lunar surface shortly after 4:31 a.m. Oct. 9, creating an impact that instruments aboard LCROSS observed for approximately four minutes. LCROSS then impacted the surface at approximately 4:36 a.m.

"This is a great day for science and exploration," said Doug Cooke, associate administrator for the Exploration Systems Mission Directorate at NASA Headquarters in Washington. "The LCROSS data should prove to be an impressive addition to the tremendous leaps in knowledge about the moon that have been achieved in recent weeks. I want to congratulate the LCROSS team for their tremendous achievement in development of this low cost spacecraft and for their perseverance through a number of difficult technical and operational challenges."‪

Other observatories reported capturing both impacts. The data will be shared with the LCROSS science team for analysis. The LCROSS team expects it to take several weeks of analysis before it can make a definitive assessment of the presence or absence of water ice.

"I am very proud of the success of this LCROSS mission team," said Daniel Andrews, LCROSS project manager at Ames. "Whenever this team would hit a roadblock, it conceived a clever work-around allowing us to push forward with a successful mission."

The images and video collected by the amateur astronomer community and the public also will be used to enhance our knowledge about the moon.

"One of the early goals of the mission was to get as many people to look at the LCROSS impacts in as many ways possible, and we succeeded," said Jennifer Heldmann, Ames' coordinator of the LCROSS observation campaign. "The amount of corroborated information that can be pulled out of this one event is fascinating."

"It has been an incredible journey since LCROSS was selected in April 2006," said Andrews. "The LCROSS Project faced a very ambitious schedule and an uncommonly small budget for a mission of this size. LCROSS could be a model for how small robotic missions are executed. This is truly big science on a small budget."

For more information about the LCROSS mission, including images and video, visit:

http://www.nasa.gov/lcross

LCROSS Viewer's Guide

Just imagine. A spaceship plunges out of the night sky, hits the ground and explodes. A plume of debris billows back into the heavens, leading your eye to a second ship in hot pursuit. Four minutes later, that one hits the ground, too. It's raining spaceships!

Put on your hard hat and get ready for action, because on Friday, Oct. 9, what you just imagined is really going to happen--and you can have a front row seat.

The impact site is crater Cabeus near the moon's south pole. NASA is guiding the Lunar Crater Observation and Sensing Satellite (LCROSS for short) and its Centaur booster rocket into the crater's floor for a spectacular double-impact designed to unearth signs of lunar water.

A computer visualization of LCROSS hitting the Moon on Oct. 9th. Credit: NASA

There are two ways to watch the show.

First, turn on NASA TV. The space agency will broadcast the action live from the Moon, with coverage beginning Friday morning at 3:15 am PDT (10:15 UT). The first hour or so, pre-impact, will offer expert commentary, status reports from mission control, camera views from the spacecraft, and telemetry-based animations.

The actual impacts commence at 7:30 am EDT (11:30 UT). The Centaur rocket will strike first, transforming 2200 kg of mass and 10 billion joules of kinetic energy into a blinding flash of heat and light. Researchers expect the impact to throw up a plume of debris as high as 10 km.

Close behind, the LCROSS mothership will photograph the collision for NASA TV and then fly right through the debris plume. Onboard spectrometers will analyze the sunlit plume for signs of water (H2O), water fragments (OH), salts, clays, hydrated minerals and assorted organic molecules.

"If there's water there, or anything else interesting, we'll find it," says Tony Colaprete, the mission's principal investigator.

Next comes the mothership's own plunge. Four minutes after the Centaur "lands," the 700 kg LCROSS satellite will strike nearby, sending another, smaller debris plume over the rim of Cabeus.

The Hubble Space Telescope, the Lunar Reconnaissance Orbiter (LRO) and hundreds of telescopes great and small on Earth will scrutinize the two plumes, looking for signs of water and the unexpected.

And that brings us to the second way to see the show: Grab your telescope.

"We expect the debris plumes to be visible through mid-sized backyard telescopes--10 inches and larger," says Brian Day of NASA/Ames. Day is an amateur astronomer and the Education and Public Outreach Lead for LCROSS. "The initial explosions will probably be hidden behind crater walls, but the plumes will rise high enough above the crater's rim to be seen from Earth."

The Pacific Ocean and western parts of North America are favored with darkness and a good view of the moon at the time of impact. Hawaii is the best place to be, with Pacific coast states of the USA a close second. Any place west of the Mississippi River, however, is a potential observing site.

When the plumes emerge from Cabeus, they will be illuminated by sunshine streaming over the polar terrain. The crater itself will be in the dark, however, permanently shadowed by its own walls. "That's good," says Day. "The crater's shadows will provide a dark backdrop for viewing the sunlit plumes."

In an earlier stage of mission planning, scientists hoped to strike a crater closer to the Moon's limb so that the plumes would billow out against the dark night sky, providing maximum contrast for observers on Earth. However, recent data from NASA's Lunar Reconnaissance Orbiter, Japan's Kaguya spacecraft and India's Chandrayaan-1 probe altered those plans.

"We've just learned that Cabeus may contain relatively-rich deposits of hydrogen and/or frozen water," says Colaprete. "Cabeus is not as close to the lunar limb as we would have liked, but it seems to offer us the best chance of hitting H2O."

The LCROSS team hopes many people—amateurs and professionals alike—will observe and photograph the plumes. "The more eyes the better," says Day. "Remember, we've never done this before. We're not 100% sure what will happen, and big surprises are possible."

Veteran amateur astronomer Kurt Fisher has prepared a 13 MB slideshow to help fellow amateurs locate and witness the plumes: download it . There is also an online LCROSS observer's group where novices can read introductory articles and chat with other observers.

"This is a wonderful opportunity for citizen scientists to join NASA in the process of discovery," says Day, who urges observers to submit their images to the LCROSS Citizen Science Site. "It's a great adventure, and anyone can participate."

Imagine that.

Dr. Tony Phillips
Science@NASA

For more information visit http://www.nasa.gov/mission_pages/LCROSS/main/LCROSS_Viewers_Guide.html

NASA Goddard Shoots the Moon to Track LRO

On certain nights, an arresting green line pierces the sky above NASA's Goddard Space Flight Center in Greenbelt, Md. It's a laser directed at the moon, visible when the air is humid. No, we're not repelling an invasion. Instead, we're tracking our own spacecraft.

28 times per second, engineers at NASA Goddard fire a laser that travels about 250,000 miles to hit the minivan-sized Lunar Reconnaissance Orbiter (LRO) spacecraft moving at nearly 3,600 miles per hour as it orbits the moon.

Goddard's Laser Ranging Facility directing a laser (green beam) toward the LRO spacecraft in orbit around the moon (white disk). The moon has been deliberately over-exposed to show the laser. Credit: Tom Zagwodzki/Goddard Space Flight Center

The first laser ranging effort to track a spacecraft beyond low-Earth orbit on a daily basis produces distance measurements accurate to about four inches (10 centimeters). For comparison, the microwave stations tracking LRO measure its range to a precision of about 65 feet (20 meters).

"Current lunar maps are not as accurate as we’ll need to return people safely to the moon," said Ronald Zellar of NASA Goddard, team lead for the LRO laser ranging system. "In order to make an accurate map, first you need to know where you are. Knowing the precise range to LRO is necessary for its instruments to produce much more accurate maps, with errors reduced to the size of humans or rovers."

"A further benefit of laser ranging to LRO is that it can improve knowledge of the moon's orientation and gravity, which are central to understanding its interior structure and to precision navigation," said Gregory Neumann, a Geophysicist at NASA Goddard.

Engineers use a telescope at the ground station on the Goddard campus to direct laser pulses toward LRO. The range to LRO is calculated by measuring how long it took the laser to reach the spacecraft.

The laser ranging to LRO is one way, meaning that the laser is directed at LRO, which records the time of arrival and sends the data back to ground stations on Earth by its radio telemetry link. This is the first time repeated, one-way tracking has been used for spacecraft ranging. Typical satellite laser ranging, used for spacecraft in low-Earth orbit, is two way, meaning the laser is simply reflected off the spacecraft and the time of flight recorded when it returns to the ground.

The advantage of LRO's one-way system is that a less expensive, lower-power laser system can be used -- especially important since the distance to LRO is hundreds of times greater than that to most Earth-orbiting spacecraft. Also, only a small receiver is needed on the spacecraft instead of a large retro-reflector array.

Goddard's Laser Ranging Facility from another side. Credit: Tom Zagwodzki/Goddard Space Flight Center

LRO's laser tracking presents unique challenges, however. First, there's the issue of avoiding interference. The laser pulses from Earth are received by a small telescope on LRO and transferred to the spacecraft’s laser altimeter instrument. The detector on this instrument performs double-duty, detecting both the laser ranging pulses as well as the pulses from its own laser reflected off the lunar surface. The instrument’s laser is used to build three-dimensional (topographic) maps of the lunar landscape and those pulses could hit the detector at the same time as the laser ranging pulses from Earth, confusing the data. So the pulses from Earth have to be carefully timed to avoid interfering with the instrument’s operation. Since the instrument sends laser pulses 28 times per second to the lunar surface, the laser ranging pulses are sent at the same rate but shifted in time to avoid interference. "It's like shooting at a spinning coin from a mile away and being able to hit it on the edge as it spins," said Neumann.

Another challenge is precise time measurement. Since the range to LRO is calculated by measuring how long it took the laser to reach the spacecraft, any variations in the time measurements will produce variations in the range estimates. LRO has a timing system that uses a crystal oscillator -- the heart of which is a vibrating crystal -- to measure time precisely. The oscillator is accurate to one part in a trillion over an hour. However, the rate at which the crystal vibrates changes with temperature, so the crystal is housed in a small oven which must be carefully controlled to maintain a stable temperature.

Then there's the difficulty of hitting a moving target. Since LRO is constantly moving in its orbit, the ground station must fire the laser pulses at a point in front of the spacecraft to compensate for the spacecraft's motion while the pulse is in-flight toward the moon. This is one of the reasons why LRO still relies on the traditional microwave tracking systems. They need the position of the spacecraft to know where to point the laser. The laser spot is 12 miles wide when it gets to the moon. Although this seems large on a human scale, it’s small in space and it would be easy to miss a tiny spacecraft moving 3,600 miles per hour. Even though the precision isn’t as great, without the microwave tracking system, the laser ranging system won’t work. This requires the LRO Mission Operations Center to track, predict, and communicate the position of the spacecraft to the laser ranging ground station.

Finally, there's the problem of bad weather; specifically, clouds. The laser can't penetrate thick cloud cover, so laser ranging is not available in those situations. Fortunately, there's plenty of opportunity to collect data over the course of LRO's one-year mission. "We're ranging to LRO whenever the moon is visible, 24 hours a day, 7 days a week," said Jan McGarry of NASA Goddard, ground system lead for laser ranging.

"Two-way satellite laser ranging (SLR) was developed at NASA Goddard in the 1960s," adds McGarry. "Since then, SLR has become a global effort, with about 30 countries participating and about 40 satellites carrying laser reflectors. NASA has eight SLR stations around the world, and Goddard is responsible for them. NASA is part of the global International Laser Ranging Service, an organization that provides a coordinated administration for all participating SLR stations and analysis centers." LRO's laser ranging effort is funded by the LRO project.

For more about Goddard's laser ranging facility, refer to:

http://lrolr.gsfc.nasa.gov/

Bill Steigerwald
NASA Goddard Space Flight Center

For more information visit http://www.nasa.gov/mission_pages/LRO/news/LRO_lr.html

Centaur is No Longer the Bridesmaid

Centaur was the unnamed companion to the Atlas V rocket when it launched from Cape Canaveral, Fla., on June 18, 2009. Their mission: lift NASA's Lunar Reconnaissance Orbiter (LRO) into its lunar orbit. Piggybacking a ride on the Centaur was also the Lunar Crater Observation and Sensing Satellite (LCROSS) that will impact the moon in October. But something is different about this mission for Centaur: instead of quietly parking itself in a long-duration orbit of the earth, Centaur accompanied the two spacecraft on their journey toward the moon. What is more, Centaur will be the center of attention for a few glorious minutes this October.

On Cape Canaveral Air Force Station's skid strip in Florida, the crane is being removed from the Centaur stage of the Atlas V rocket after placing the Centaur on the flatbed truck. The Centaur will be transported to the Astrotech facility in Titusville, Fla. Photo credit: NASA/Cory Huston

The main LCROSS mission objective is to confirm the presence or absence of water ice in a permanently shadowed crater near a lunar polar region. Mission scientists have determined that the best way to do this is to send one or more objects into the surface of the moon to generate a large plume that can be studied to determine the presence of water ice. LCROSS is a small spacecraft, and besides not being able to make a major impact, its primary role is to observe a larger impact. That creates the opportunity for Centaur to take center stage.

LCROSS, still attached to its Centaur upper stage rocket, executed a fly-by of the moon on June 23, 2009 and entered into an elongated Earth orbit to position LCROSS for impact on a lunar pole. On final approach, the shepherding spacecraft and Centaur will separate. The Centaur will act as a heavy impactor to create a debris plume that will rise above the lunar surface. Projected impact at the lunar South Pole is currently: Oct 9, 2009 at 7:30 a.m. EDT. The Centaur will excavate a crater approximately 20 meters wide and almost 3 meters deep. More than 250 metric tons of lunar dust will be lofted above the surface of the moon.

Following four minutes behind, the shepherding spacecraft will fly through the debris plume, collecting and relaying data back to Earth before impacting the lunar surface and creating a second debris plume.

On Cape Canaveral Air Force Station's Launch Complex 41, the crane lifts the Centaur upper stage into the Vertical Integration Facility for installation onto the Atlas V first stage, already in the tower. Photo credit: NASA/Jack Pfaller.

For almost 30 years, the NASA Glenn Research Center in Cleveland, Ohio, was responsible for the technical and cost and schedule management of the Centaur rocket. This program had an extraordinary operational success record. It was developed as an upper stage launch vehicle to be used with a first stage booster rocket, the Atlas rocket. Centaur's first mission objective was to send the unmanned Surveyor spacecraft to the Moon. Centaur has been used to boost satellites into orbit and propel probes into space. Mariner, Pioneer, Viking and Voyager spacecraft all got a boost from Centaur and provided invaluable data on these planets. Centaur also helped to revolutionize communication and expand the frontiers of space. In all, Glenn used Centaur for more than 100 unmanned launches. Centaur has quietly continued as the upper stage of the Atlas family of rockets from United Launch Alliance and the retired Titan IV from Lockheed Martin.

For each of its previous missions, Centaur quietly did its job and retreated out of the limelight. This time, Centaur is going out in style!

Go Centaur!

David DeFelice NASA Glenn Research Center

Note: NASA’s Ames Research Center, Moffett Field, Calif., is overseeing the development of the LCROSS mission with its spacecraft and integration partner, Northrop Grumman, Redondo Beach, Calif.

Read more about Centaur's history.

For more information visit http://www.nasa.gov/mission_pages/LCROSS/main/centaur_full_story.html

Lunar South Pole -- Out of the Shadows

During the LRO Commissioning Phase, the high-resolution Lunar Reconnaissance Orbiter Camera (LROC) captured this 1-m pixel scale (angular resolution) two-image mosaic of the lunar south pole, which is located on the rim of the 19-km diameter Shackleton crater. At meter scales features such as boulders and ridges can be mapped, paving the way for future explorers. Right now we know little of the poles and much is to be learned from the data now being returned from LRO. The rim of Shackleton crater is a prime candidate for future human exploration due to its proximity to permanently shadowed regions and nearby peaks that are illuminated for much of the year. The permanent shadow may harbor cold-trapped volatiles deposited as comets and asteroids impacted the Moon over the past billion years or more. Highly illuminated peaks provide opportunities for solar power during most of the year for future human habitation.

Over the past year the Japanese Kaguya and Indian Chandrayaan spacecraft gave us our first high-resolution look at the lunar south pole and Shackleton crater and revealed an exceptionally deep and rugged interior for its size. Usually craters fill in with time as their walls slump and material from afar is thrown in by distant impacts. Since Shackleton crater is so deep and rough inside scientists might infer it is relatively young. However, much of the rim of Shackleton appears rounded and is peppered with smaller craters – indications of a relatively ancient age. Right now it is not clear if Shackleton crater is old or young. Many more LROC Narrow Angle Camera (NAC) images of this area will be obtained over the coming months as the south pole emerges from the shadows of winter and a more complete picture will appear.

The full NAC mosaic reveals a shelf on the southeast flank of the crater that is more than two kilometers across and perfectly suitable for a future landing. The extreme Sun angle gives the surface an exaggerated rough appearance, but if you look closely at this scale any area that is between the small craters might make a good landing site. The NAC can see details with ten times greater resolution than previous datasets allowing lunar geologists to map features at a human scale. Where should explorers land, and where should they visit once on the surface? Where can they find resources, and where can they sample a diversity of geologic materials? Over the coming months the whole area will be characterized in detail by all of the LRO instruments, and scientists will have the data to investigate these questions and more.

The Lunar Reconnaissance Orbiter Camera was built by Malin Space Science Systems in San Diego, California, and is operated from the LROC Science Operations Center, part of the School of Earth and Space Exploration at Arizona State University in Tempe, Arizona.

Related Link:

› For more images and information

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

The Ultimate Long Distance Communication

Anyone who's vacationed in the mountains or lived on a farm knows that it's hard to get good internet access or a strong cell phone signal in a remote area. Communicating across great distances has always been a challenge. So when NASA engineers designed the Lunar Reconnaissance Orbiter (LRO), they knew it would need an extraordinary communications system.

Over the next year, the LRO, NASA's diligent robotic scout, will collect more information about the moon's surface and environment than any previous mission. It takes a powerful system to send all of this information more than 238,800 miles back to Earth.

A 13-inch-long tube, called a Traveling Wave Tube Amplifier, is making it possible for scientists to receive massive amounts of images and data from the orbiter at an unusually fast rate. It is the first high data rate K-band transmitter to fly on a NASA spacecraft.

With this new amplifier, LRO can transmit 461 gigabytes of data per day. That's more information than you can find in a four-story library. And it transmits this information at a rate of up to 100 megabytes per second. By comparison, typical high-speed internet service provides about 1 to 3 megabytes per second.

L-3 Communications Electron Technologies built the amplifier under the supervision of NASA's Glenn Research Center in Cleveland. The device uses electrodes in a vacuum tube to amplify microwave signals to high power. It's ideal for sending large amounts of data over a long distance because it provides more power and more efficiency than its alternative, the transistor amplifier.

This image shows cratered regions near the moon's Mare Nubium region, as photographed by the Lunar Reconnaissance Orbiter. Credit: NASA

As the orbiter collects information about the moon's geography, climate and environment, the communication system transmits this information to a receiver at a Ka band antenna network at White Sands Test Facility in New Mexico. Scientists are using the data to compile high-resolution, 3D maps of the lunar surface.

"We're sending back more data than ever, faster and it's nearly real time," said Glenn project manager Todd Peterson.

Traveling Wave Tube Amplifiers have been used for other planetary missions, such as Kepler and Cassini, but previous designs were less powerful. According to Rainee Simons, chief of Glenn's Electron and Optoelectronic Device Branch, engineers had to redesign the internal circuitry of the amplifier.

"In order to provide the power and frequency needed to send communications from the vicinity of the moon, it had to be custom designed and handmade," he said.

The orbiter's Traveling Wave Tube Amplifier is also more efficient than previous amplifiers. When it comes to launching satellites, weight means money. The heavier the spacecraft, the more fuel it needs to reach orbit. Because the new amplifier packs more power into a lighter design than previous microwave amplifiers, it's cheaper to fly.

The amplifier underwent vigorous spaceflight testing -- including vibration, thermal vacuum, radiation and electromagnetic interference tests -- to ensure that it could withstand the intense conditions of launch and lunar orbit.

Simons, Peterson and other members of the Glenn team were on standby when LRO entered its final orbit and began transmitting data. They were thrilled to hear that it's working properly, not only because LRO is a vital step toward returning humans to the moon, but also because they believe the new amplifier can improve life on Earth in countless ways.

This image shows cratered regions near the moon's Mare Nubium region, as photographed by the Lunar Reconnaissance Orbiter. Credit: NASA

If used on communication satellites, it could allow for much better tracking, monitoring and control of transoceanic flights and ships traveling beyond the reach of radar.

It also could enable real-time data transfer from future Earth-orbiting satellites. Such satellites are used to track migratory animals, endangered species, icebergs, volcanic eruptions and forest fires, and to aid in search and rescue operations. They're used to study climate change and meteorology as well.

According to Simons, by collecting more timely data about the interaction of our atmosphere, ocean and land, we could save lives and property during severe weather.

"This technology has the potential to create a better world," he said.

Jan Wittry (SGT, Inc.)
NASA's Glenn Research Center

For more information visit nasa.gov