Cosmic rays threaten future deep-space astronaut missions

Artist's rendition of the Lunar Reconnaissance Orbiter (LRO) at the moon. 

The CRaTER telescope is seen pointing out at the bottom right center of the LRO spacecraft.

Credit: Illustration by Chris Meaney/NASA

Crewed missions to Mars remain an essential goal for NASA, but scientists are only now beginning to understand and characterise the radiation hazards that could make such ventures risky, concludes a new paper by University of New Hampshire (UNH) scientists.

In a paper published online in the journal Space Weather, associate professor Nathan Schwadron of the UNH Institute for the Study of Earth, Oceans, and Space (EOS) and the department of physics says that due to a highly abnormal and extended lack of solar activity, the solar wind is exhibiting extremely low densities and magnetic field strengths, which causes dangerous levels of hazardous radiation to pervade the space environment.

"The behaviour of the sun has recently changed and is now in a state not observed for almost 100 years," says Schwadron, lead author of the paper and principal investigator for the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on NASA's Lunar Reconnaissance Orbiter (LRO).

He notes that throughout most of the space age, the sun's activity has shown a clockwork 11-year cycle, with approximately six- to eight-year lulls in activity (solar minimum) followed by two- to three-year periods when the sun is more active.

"However, starting in about 2006, we observed the longest solar minimum and weakest solar activity observed in the space age."

These conditions brought about the highest intensities of galactic cosmic rays seen since the beginning of the space age, which have created worsening radiation hazards that potentially threaten future deep-space astronaut missions.

"While these conditions are not necessarily a showstopper for long-duration missions to the moon, an asteroid, or even Mars, galactic cosmic ray radiation in particular remains a significant and worsening factor that limits mission durations," says Schwadron.

The study is the capstone article in the Space Weather CRaTER Special Issue, which provides comprehensive findings on space-based radiation as measured by the UNH-led detector.

The data provide critical information on the radiation hazards that will be faced by astronauts on extended missions to deep space such as those to Mars.

"These data are a fundamental reference for the radiation hazards in near Earth 'geospace' out to Mars and other regions of our sun's vast heliosphere," says Schwadron.

At the heart of CRaTER is material called "tissue equivalent plastic," a stand-in for human muscle capable of gauging radiation dosage. Ionizing radiation from galactic cosmic rays and solar energetic particles remains a significant challenge to long-duration crewed missions to deep space.

Human beings face a variety of consequences ranging from acute effects (radiation sickness) to long-term effects including cancer induction and damage to organs including the heart and brain.

The high radiation levels seen during the sun's last minimum cycle limits the allowable days for typical astronauts behind spacecraft shielding.

Given the trend of reducing solar output, the allowable days in space for astronauts is dropping and estimated to be 20 percent lower in the coming solar minimum cycle as compared to the last minimum cycle.

Journal Reference:
N. A. Schwadron, J. B. Blake, A. W. Case, C. J. Joyce, J. Kasper, J. Mazur, N. Petro, M. Quinn, J. A. Porter, C. W. Smith, S. Smith, H. E. Spence, L. W. Townsend, R. Turner, J. K. Wilson, C. Zeitlin. Does the worsening galactic cosmic radiation environment observed by CRaTER preclude future manned deep-space exploration? Space Weather, 2014; DOI: 10.1002/2014SW001084

NASA LRO Images: Lunar Pits Could Shelter Astronauts

This video shows images from NASA's LRO spacecraft of various lunar pits. Since 2009, NASA's Lunar Reconnaissance Orbiter (LRO) has spotted hundreds of conspicuous holes on the Moon. 

These steep-walled "pits" might lead to underground environments sheltered from radiation, meteorite impacts, and extreme temperatures, making them valuable sites for future exploration.

This is a spectacular high-Sun view of the Mare Tranquillitatis pit crater revealing boulders on an otherwise smooth floor. 

This image from LRO's NAC is 400 meters (1,312 feet) wide, north is up. 

Image Credit: NASA /GSFC /Arizona State University.

While the moon's surface is battered by millions of craters, it also has over 200 holes; steep-walled pits that in some cases might lead to caves that future astronauts could explore and use for shelter, according to new observations from NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft.

The pits range in size from about 5 meters (~5 yards) across to more than 900 meters (~984 yards) in diameter, and three of them were first identified using images from the Japanese Kaguya spacecraft.

Hundreds more were found using a new computer algorithm that automatically scanned thousands of high-resolution images of the lunar surface from LRO's Narrow Angle Camera (NAC).

"Pits would be useful in a support role for human activity on the lunar surface," said Robert Wagner of Arizona State University, Tempe, Arizona.

"A habitat placed in a pit, ideally several dozen meters back under an overhang, would provide a very safe location for astronauts: no radiation, no micrometeorites, possibly very little dust, and no wild day-night temperature swings."

Wagner developed the computer algorithm, and is lead author of a paper on this research now available online in the journal Icarus.

Most pits were found either in large craters with impact melt ponds, areas of lava that formed from the heat of the impact and later solidified, or in the lunar maria, dark areas on the moon that are extensive solidified lava flows hundreds of miles across. In ancient times, the maria were thought to be oceans; "maria" is the Latin word for "seas."

Various cultures have interpreted the patterns formed by the maria features in different ways; for example, some saw the face of a man, while others saw a rabbit or a boy carrying a bundle of sticks on his back.

These images from NASA's LRO spacecraft show all of the known mare pits and highland pits. Each image is 222 meters (about 728 feet) wide.

Image Credit: NASA /GSFC /Arizona State University

The pits could form when the roof of a void or cave collapses, perhaps from the vibrations generated by a nearby meteorite impact, according to Wagner.

However, he noted that from their appearance in the LRO photos alone, there is little evidence to point to any particular cause.

The voids could be created when molten rock flowed under the lunar surface; on Earth, lava tubes form when magma flows beneath a solidified crust and later drains away.

The same process could happen on the moon, especially in a large impact crater, the interior of which can take hundreds of thousands of years to cool, according to Wagner.

After an impact crater forms, the sides slump under lunar gravity, pushing up the crater's floor and perhaps causing magma to flow under the surface, forming voids in places where it drains away.

Exploring impact melt pits would pin down the nature of the voids in which they form. "They are likely due to melt flow within the pond from uplift after the surface has solidified, but before the interior has cooled," said Wagner.

"Exploring impact melt pits would help determine the magnitude of this uplift, and the amount of melt flow after the pond is in place."

Exploring the pits could also reveal how oceans of lava formed the lunar maria.

"The mare pits in particular would be very useful for understanding how the lunar maria formed. We've taken images from orbit looking at the walls of these pits, which show that they cut through dozens of layers, confirming that the maria formed from lots of thin flows, rather than a few big ones."

"Ground-level exploration could determine the ages of these layers, and might even find solar wind particles that were trapped in the lunar surface billions of years ago," said Wagner.

To date, the team has found over 200 pits spread across the melt ponds of 29 craters, which are considered geologically young "Copernican" craters at less than a billion years old; eight pits in the lunar maria, three of which were previously known from images from the Japanese Kaguya orbiter; and two pits in highlands terrain.

The general age sequence matches well with the pit distributions, according to Wagner.

"Impact melt ponds of Copernican craters are some of the younger terrains on the moon, and while the maria are much older at around three billion years old, they are still younger and less battered than the highlands."

"It's possible that there's a 'sweet spot' age for pits, where enough impacts have occurred to create a lot of pits, but not enough to destroy them," said Wagner.

NASA LRO Mission and North America to Experience Total Lunar Eclipse

On April 15th, 2014 there will be a total lunar eclipse visible from North America. Noah Petro, LRO Deputy Project Scientist, discusses this unique event and what effect it will have on the Lunar Reconnaissance Orbiter (LRO).

When people in North America look up at the sky in the early morning hours of April 15, they can expect the moon to look a little different.

A total lunar eclipse is expected at this time, a phenomenon that occurs when the Earth, moon and sun are in perfect alignment, blanketing the moon in the Earth's shadow.

Although lunar eclipses happen multiple times in a year during a full moon, this eclipse will be a particularly unusual viewing opportunity for North America.

Since the Earth's Western Hemisphere will be facing the moon during the eclipse, the continent will be in prime position to view it from start to finish.

In addition, the eclipse will coincide with nighttime in North America. The entire continent won't be able to witness a full lunar eclipse in its entirety again until 2019.

"Sometimes they'll happen and you'll have to be somewhere else on Earth to see them," said Noah Petro, Lunar Reconnaissance Orbiter deputy project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "Most [residents] of the continental United States will be able to see the whole thing."

For those who are awake to watch the eclipse, which is scheduled to begin around 2:00 a.m. EDT and last over three hours, Petro said there would be several changes people can witness.

When the moon first enters the Earth's partial shadow, know as the penumbra, a dark shadow will begin creeping across the moon.

This will give the illusion that the moon is changing phases in a matter of minutes instead of weeks.

"Eventually there will be a chunk of darkness eating the moon," Petro said.

NASA LRO: Wet or Dry Moon

The Moon's status as a "dry" rock in space has long been questioned. Competing theories abound as to the source of the H20 in the lunar soil, including delivery of water to the Moon by comets.

This week, Tartèse et al announced in Geology that new analyses of lunar soil samples demonstrates that basalts from the Moon's mantle contain hydrogen from water indigenous to Earth.

According to the authors, their work is "challenging the paradigm of a "dry" Moon, and arguing that some portions of the lunar interior are as wet as some regions of the Earth's mantle."


This video from NASA Goddard shows how NASA’s Lunar Reconnaissance Orbiter (LRO) is helping scientists understand where water is likely to exist on the south pole of the Moon. 

Credit: NASA Goddard on YouTube

Since the 1960's, scientists have suspected that frozen water could survive in cold, dark craters at the Moon's poles.

While previous lunar missions have detected hints of water on the Moon, new data from the Lunar Reconnaissance Orbiter (LRO) pinpoints areas near the south pole where water is likely to exist.

The key to this discovery is hydrogen, the main ingredient in water: LRO uses its Lunar Exploration Neutron Detector (LEND), to measure how much hydrogen is trapped within the lunar soil.

By combining years of LEND data, scientists see mounting evidence of hydrogen-rich areas near the Moon's south pole, strongly suggesting the presence of frozen water.

More information: Romain Tartèse, Mahesh Anand, Francis M. McCubbin, Stephen M. Elardo, Charles K. Shearer, and Ian A. Franchi. "Apatites in lunar KREEP basalts: The missing link to understanding the H isotope systematics of the Moon." Geology, G35288.1, first published on February 25, 2014, DOI: 10.1130/G35288.1

NASA LRO: Interactive mosaic of the Moon's North Pole

A new interactive mosaic from NASA's Lunar Reconnaissance Orbiter (LRO) covers the north pole of the moon from 60 to 90 degrees north latitude at a resolution of 6-1/2 feet (2 meters) per pixel. 

Close-ups of Thales crater (right side) zoom in to reveal increasing levels of detail. 

Credit: NASA /GSFC /Arizona State University

Scientists, using cameras aboard NASA's Lunar Reconnaissance Orbiter (LRO), have created the largest high resolution mosaic of our moon's north polar region.

The six-and-a-half feet (two-meters)-per-pixel images cover an area equal to more than one-quarter of the United States.

Web viewers can zoom in and out, and pan around an area.

Constructed from 10,581 pictures, the mosaic provides enough detail to see textures and subtle shading of the lunar terrain.

Consistent lighting throughout the images makes it easy to compare different regions.

"This unique image is a tremendous resource for scientists and the public alike," said John Keller, LRO project scientist at NASA's Goddard Space Flight Center, Greenbelt, Md.

"It's the latest example of the exciting insights and data products LRO has been providing for nearly five years."

The images making up the mosaic were taken by the two LRO Narrow Angle Cameras, which are part of the instrument suite known as the Lunar Reconnaissance Orbiter Camera (LROC).

The cameras can record a tremendous dynamic range of lit and shadowed areas.

"Creation of this giant mosaic took four years and a huge team effort across the LRO project," said Mark Robinson, principal investigator for the LROC at Arizona State University in Tempe.

"We now have a nearly uniform map to unravel key science questions and find the best landing spots for future exploration."

The entire image measures 931,070 pixels square – nearly 867 billion pixels total.

A complete printout at 300 dots per inch – considered crisp resolution for printed publications, would require a square sheet of paper wider than a professional U.S. football field and almost as long.

If the complete mosaic were processed as a single file, it would require approximately 3.3 terabytes of storage space.

Instead, the processed mosaic was divided into millions of small, compressed files, making it manageable for users to view and navigate around the image using a web browser.

LRO entered lunar orbit in June 2009 equipped with seven instrument suites to map the surface, probe the radiation environment, investigate water and key mineral resources, and gather geological clues about the moon's evolution.

Researchers used additional information about the moon's topography from LRO's Lunar Orbiter Laser Altimeter, as well as gravity information from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission, to assemble the mosaic.

NASA's LRO mission: Musical space-weather reports

The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on NASA's Lunar Reconnaissance Orbiter has six detectors to monitor the energetic charged particles from galactic cosmic rays and solar events. 

Credit: NASA/GSFC

The latest tool for checking space weather is an internet radio station fed by data from NASA's Lunar Reconnaissance Orbiter (LRO).

The radio station essentially operates in real time, receiving measurements of how much radiation the spacecraft is experiencing and converting those into a constant stream of music.

The radiation levels determine which instrument is featured, the musical key being used and the pitches played.

"Our minds love music, so this offers a pleasurable way to interface with the data," said the leader of the music project, Marty Quinn of the University of New Hampshire, Durham.

"It also provides accessibility for people with visual impairments." The radiation levels are determined by LRO's Cosmic Ray Telescope for the Effects of Radiation (CRaTER).

Equipped with six detectors, CRaTER monitors the energetic charged particles from galactic cosmic rays and solar events. The instrument makes two kinds of crucial measurements.

One type studies the interaction of radiation in space with a material that is like human tissue; this is helping scientists assess the effects that exposure would have on people and organisms.

The other type looks at radiation hitting the moon and the products generated by that interaction, which provides a way to explore the composition of the regolith on the moon.

"CRaTER has discovered wide-ranging and fundamental aspects of such radiation," said Nathan Schwadron, the principal investigator for CRaTER.

"For example, we have discovered that tissue-equivalent plastics and other lightweight materials can provide even more effective protection than standard shielding, such as aluminum."

Each detector on CRaTER reports the number of particles registered every second.

These counts are relayed to CRaTER Live Radio, where software converts the numbers into pitches in a four-octave scale. Six pitches are played every second, one for each detector.

Higher, tinkly pitches indicate less activity, whereas lower, somber-sounding pitches indicate more activity.

The software selects the primary instrument and a musical key based on recent activity. At the lowest radiation levels, the main instrument will be a piano, playing pitches from one of the major scales.

But as the peak radiation level climbs, one of the minor scales will be selected instead, and the piano will be replaced by one of seven other instruments.

NASA LRO: Metamorphosis of moon's water ice explained

Panoramic lunar view taken by the Lunar Reconnaissance Orbiter Camera of the north rim of Cabeus crater. 

The distance from left to right is about 75 kilometers (46 miles). 

Image courtesy of NASA/GSFC/Arizona State Univ.

Using data gathered by NASA's Lunar Reconnaissance Orbiter (LRO) mission, scientists believe they have solved a mystery from one of the solar system's coldest regions—a permanently shadowed crater on the moon.

They have explained how energetic particles penetrating lunar soil can create molecular hydrogen from water ice.

The finding provides insight into how radiation can change the chemistry of water ice throughout the solar system.

Space scientists from the University of New Hampshire and NASA's Goddard Space Flight Center have published their results online in the Journal of Geophysical Research (JGR): Planets.

Lead author of the paper is research scientist Andrew Jordan of the University of New Hampshire's Institute for the Study of Earth, Oceans, and Space (EOS).

Discovering molecular hydrogen on the moon was a surprise result from NASA's Lunar Crater Observation Sensing Satellite (LCROSS) mission, which crash-landed the LCROSS satellite's spent Centaur rocket at 5,600 miles per hour into the Cabeus crater in the permanently shadowed region of the moon. 

These regions have never been exposed to sunlight and have remained at temperatures near absolute zero for billions of years, thus preserving the pristine nature of the lunar soil, or regolith.

Instruments on board LCROSS trained on the resulting immense debris plume detected water vapor and water ice, the mission's hoped-for quarry, while LRO, already in orbit around the moon, saw molecular hydrogen—a surprise.

"LRO's Lyman Alpha Mapping Project (LAMP), detected the signature of molecular hydrogen, which was unexpected and unexplained," says Jordan.

Jordan's JGR paper, "The formation of molecular hydrogen from water ice in the lunar regolith by energetic charged particles," quantifies an explanation of how molecular hydrogen, which is comprised of two hydrogen atoms and denoted chemically as H2, may be created below the moon's surface.

"After the finding, there were a couple of ideas for how molecular hydrogen could be formed but none of them seemed to work for the conditions in the crater or with the rocket impact." Jordan says.

"Our analysis shows that the galactic cosmic rays, which are charged particles energetic enough to penetrate below the lunar surface, can dissociate the water, H2O, into H2 through various potential pathways."

That analysis was based on data gathered by the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument aboard the LRO spacecraft.

Jordan is a member of the CRaTER scientific team, which is headed up by principal investigator Nathan Schwadron of EOS.

Schwadron, a co-author on the JGR paper, was the first to suggest energetic particles as the possible mechanism for creating molecular hydrogen.

CRaTER characterises the global lunar radiation environment by measuring radiation dose rates from galactic cosmic rays and solar energetic particles.

Says Jordan, "We used the CRaTER measurements to get a handle on how much molecular hydrogen has been formed from the water ice via charged particles."

Jordan's computer model incorporated the CRaTER data and showed that these energetic particles can form between 10 and 100 percent of the H2 measured by LAMP.

The study notes that narrowing down that percent range requires particle accelerator experiments on water ice to more accurately gauge the number of chemical reactions that result per unit of energy deposited by cosmic rays and solar energetic particles.

NASA Grail Twin Probes Final Flight Path

The NASA GRAIL twin probes' final flight path into their crash site, imaged with data from NASA's Lunar Reconnaissance Orbiter (LRO). 

Credit: NASA/JPL-Caltech/GSFC/ASU

Two space probes that successfully mapped variations in the Moon's gravity field have been deliberately crashed into the lunar surface in a dramatic end to their mission.

They are just the latest in a string of probes to leave their shattered remains on the Moon. The impacts of the GRAIL probes, Ebb and Flow, into a 2.4 km high (1.5 miles) mountain near the lunar north pole, was deliberate and planned in great detail.

NASA decided to destroy the craft in a controlled manoeuvre rather than take the risk, however tiny, that they might later hit one of the historic landing sites of Apollo and unmanned probes.

The two spacecraft, each the size of a washing machine, fired their thrusters one last time to burn up the last of their fuel. They dropped into a lower orbit and hit the peak's southern face, near a crater called Goldschmidt, at 6,050 kph (3,760 mph).

NASA LRO Finds Further Evidence of Water On The Moon

Scientists from NASA and Boston University have found small patches of ice in the Shackleton Crater, at the south pole of the Moon.

Five to 10 percent of the crater wall is made of ice, they said, after analyzing data obtained from the Mini-RF radar on Nasa's Lunar Reconnaissance Orbiter.

"These terrific results from the Mini-RF team contribute to the evolving story of water on the moon. Several of the instruments on LRO have made unique contributions to this story, but only the radar penetrates beneath the surface to look for signatures of blocky ice deposits," said John Keller, a scientist at NASA's Goddard Space Flight Center.

Scientists believe that because the interior of the Shackleton crater lies in permanent shadow it is cold enough for ice to accumulate.

"Inside the crater, we don't see evidence for glaciers like on earth. Glacial ice has a whopping radar signal, and these measurements reveal a much weaker signal consistent with rugged terrain and limited ice," said Bradley Thomson, researcher at Boston University.

Lunar Reconnaissance Orbiter spectrometer detects helium in Moon's atmosphere

The Lyman Alpha Mapping Project (LAMP) aboard LRO (shown here in a pre-flight photo) uses a novel method to peer into the perpetual darkness of the moon's so-called permanently shadowed regions.

LAMP "sees" the lunar surface using the ultraviolet light from nearby space and stars, which bathes all bodies in space in a soft glow of ultraviolet light. (Credit: NASA Goddard/Debbie McCallum)

Geophysical Research Letters, Vol. 39, doi:10.1029/2012GL051797 , 2012.

Scientists using the Lyman Alpha Mapping Project (LAMP) aboard NASA's Lunar Reconnaissance Orbiter have made the first spectroscopic observations of the noble gas helium in the tenuous atmosphere surrounding the Moon.

These remote-sensing observations complement in-situ measurements taken in 1972 by the Lunar Atmosphere Composition Experiment (LACE) deployed by Apollo 17.

Although LAMP was designed to map the lunar surface, the team expanded its science investigation to examine the far ultraviolet emissions visible in the tenuous atmosphere above the lunar surface, detecting helium over a campaign spanning more than 50 orbits.

Because helium also resides in the interplanetary background, several techniques were applied to remove signal contributions from the background helium and determine the amount of helium native to the Moon.

Geophysical Research Letters published a paper on this research in 2012. "The question now becomes, does the helium originate from inside the Moon, for example, due to radioactive decay in rocks, or from an exterior source, such as the solar wind?" says Dr. Alan Stern, LAMP principal investigator and associate vice president of the Space Science and Engineering Division at Southwest Research Institute.

With support from LRO's suite of instruments, LAMP has previously determined that hydrogen, mercury and other volatile substances are present in the permanently shaded regions (PSRs) of the moon.

It has also observed PSRs are darker at far-ultraviolet wavelengths and redder than nearby surfaces that receive sunlight.

These darker regions indicate "fluffy" soils, while the reddening is consistent with the presence of water frost.

In a related study led by Dr. Paul Feldman of Johns Hopkins University and published in Icarus, observations showed day-to-day variations in helium abundances, possibly varying with the solar wind, and also significantly decreasing when the Moon passed behind Earth out of sight from the solar wind.

"If we find the solar wind is responsible, that will teach us a lot about how the same process works in other airless bodies," says Stern.

 If spacecraft observations show no such correlation, radioactive decay or other internal lunar processes could be producing helium that diffuses from the interior or that releases during lunar quakes.

NASA Researchers Estimate Ice Content of Crater at Moon's South Pole

Elevation (left) and shaded relief (right) image of Shackleton, a 21-km-diameter (12.5-mile-diameter) permanently shadowed crater adjacent to the lunar south pole. 

The structure of the crater's interior was revealed by a digital elevation model constructed from over 5 million elevation measurements from the Lunar Orbiter Laser Altimeter. 

Credit: NASA/Zuber, M.T. et al., Nature, 2012

NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft has returned data that indicate ice may make up as much as 22 percent of the surface material in a crater located on the moon's south pole.

The team of NASA and university scientists using laser light from LRO's laser altimeter examined the floor of Shackleton crater.

They found the crater's floor is brighter than those of other nearby craters, which is consistent with the presence of small amounts of ice.

This information will help researchers understand crater formation and study other uncharted areas of the moon. The findings are published in Thursday's edition of the journal Nature.

"The brightness measurements have been puzzling us since two summers ago," said Gregory Neumann of NASA's Goddard Space Flight Center in Greenbelt, Md., a co-author on the paper.

"While the distribution of brightness was not exactly what we had expected, practically every measurement related to ice and other volatile compounds on the moon is surprising, given the cosmically cold temperatures inside its polar craters."

The spacecraft mapped Shackleton crater with unprecedented detail, using a laser to illuminate the crater's interior and measure its albedo or natural reflectance. The laser light measures to a depth comparable to its wavelength, or about a micron.

That represents a millionth of a meter, or less than one ten-thousandth of an inch. The team also used the instrument to map the relief of the crater's terrain based on the time it took for laser light to bounce back from the moon's surface. The longer it took, the lower the terrain's elevation.

NASA Lunar Recon Orbiter: Reveals Recent Geological Activity on the Moon

This shows the largest of the newly detected graben found in highlands of the lunar farside.

The broadest graben is about 500 meters (1,640 feet) wide and topography derived from Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) stereo images indicates they are almost 20 meters (almost 66 feet) deep. 

(Credit: NASA/Goddard/Arizona State University/Smithsonian Institution)

New images from NASA's Lunar Reconnaissance Orbiter (LRO) spacecraft show the moon's crust is being stretched, forming minute valleys in a few small areas on the lunar surface.

Scientists propose this geologic activity occurred less than 50 million years ago, which is considered recent compared to the moon's age of more than 4.5 billion years.

A team of researchers analyzing high-resolution images obtained by the Lunar Reconnaissance Orbiter Camera (LROC) show small, narrow trenches typically much longer than they are wide.

This indicates the lunar crust is being pulled apart at these locations.

These linear valleys, known as graben, form when the moon's crust stretches, breaks and drops down along two bounding faults. A handful of these graben systems have been found across the lunar surface.

Read more and watch the NASA Video here

NASA Lunar Rec Orbiter: LAMP sees water frost on dark side of Moon

New maps produced by the Lyman Alpha Mapping Project aboard NASA’s Lunar Reconnaissance Orbiter reveal features at the Moon’s northern and southern poles in regions that lie in perpetual darkness.

LAMP, developed by Southwest Research Institute, uses a novel method to peer into these so-called permanently shadowed regions (PSRs), making visible the invisible.

LAMP’s principal investigator is Dr. Alan Stern, associate vice president of the SwRI Space Science and Engineering Division

The LAMP maps show that many PSRs are darker at far-ultraviolet wavelengths and redder than nearby surface areas that receive sunlight.

The darker regions are consistent with large surface porosities — indicating “fluffy” soils — while the reddening is consistent with the presence of water frost on the surface.

“Our results suggest there could be as much as 1 to 2 percent water frost in some permanently shadowed soils,” says author Dr. Randy Gladstone, an Institute scientist in the SwRI Space Science and Engineering Division.

“This is unexpected because naturally occurring interplanetary Lyman-alpha was thought to destroy any water frost before it could accumulate.”

The LAMP team estimates that the loss of water frost is about 16 times slower than previously believed.

In addition, the accumulation of water frost is also likely to be highly dependent on local conditions, such as temperature, thermal cycling and even geologically recent “impact gardening” in which micrometeoroid impacts redistribute the location and depth of volatile compounds.

Finding water frost at these new locations adds to a rapidly improving understanding of the Moon’s water and related species, as discovered by three other space missions through near-infrared emissions observations and found buried within the Cabeus crater by the LCROSS impactor roughly two years ago.

During LRO’s nominal exploration mission, LAMP added to the LCROSS results by measuring hydrogen, mercury and other volatile gases ejected along with the water from the permanently shaded soils of the Moon’s Cabeus crater.

“An even more unexpected finding is that LAMP’s technique for measuring the lunar Lyman-alpha albedo indicates higher surface porosities within PSRs, and supports the long-postulated presence of tenuous ‘fairy-castle’ like arrangements of surface grains in the PSR soils,” says co-author Dr. Kurt Retherford, a senior research scientist also in SwRI’s Space Science and Engineering Division.

Comparisons with future LAMP maps created using data gathered from the Moon’s day side will prove helpful for revealing more about the presence of water frost, as well as the surface porosities of the darker surface features observed.

The LAMP team is also eager to apply the Lyman-alpha technique elsewhere on the Moon and on other solar system objects such as Mercury.

LRO’s findings are expected to be valuable to the future consideration of a permanent Moon base. The permanently shadowed regions of the Moon are revealing themselves to be some of the most exotic places in the solar system, well worthy of future exploration, says Retherford.

Any discovery of water frost and other resources in the area also could reduce the need to transport resources from Earth to a base at the pole.

The paper, “Far-Ultraviolet Reflectance Properties of the Moon’s Permanently Shadowed Regions,” by G.R. Gladstone, K.D. Retherford, A.F. Egan, D.E. Kaufmann, P.F. Miles, et al., was published in the Jan. 7 issue of the Journal of Geophysical Research.

NASA Goddard Space Flight Center in Greenbelt, Md., developed and manages the LRO mission.

NASA Lunar Recon (LRO): Sharpest Ever Moon Map

NASA's Lunar Reconnaissance Orbiter (LRO) science team has released the highest resolution near-global topographic map of the Moon ever created.

Though the Moon is the Earth's closest neighbour, yet knowledge of its morphology is still limited.

"Due to the limitations of previous missions, a global map of the Moon's topography at high resolution has not existed until now," said NASA while releasing the map.

LRO's Wide Angle Camera and the Lunar Orbiter Laser Altimeter instrument will help scientists portray the shape of the entire Moon at high resolution accurately.

Check out below the new topographic map that shows the Moon's surface shape and features with a pixel scale close to 328 feet.

Short Sharp Science: Lunar rainbow recreates Dark Side of the Moon

Cian O'Luanaigh, reporter

This image of the moon's surface was snapped by the Lunar Reconnaissance Orbiter's Wide Angle Camera with the sun directly overhead. Under these conditions, surface features show no shadows, causing an increase in brightness in the image called an "opposition surge".

The camera uses different filters to observe different pieces of the ground at different times. Here, the 689, 643, and 604 nanometre filters are displayed in red, green, and blue, respectively.

Because the opposition surge is seen by different filters at different times, when the observations from separate filters are combined to a single colour image, the shifting bright spot is seen as a rainbow, inadvertently recreating Pink Floyd's Dark Side of the Moon.

(Image: NASA/GSFC/Arizona State University)

Lunar Reconnaissance Orbiter (LRO) - Goddard Flckr

Click on the picture to connect you to a spectacular presentation of LRO images from the Goddard photo and video blog.