Goddard awarded LRO science

Greenbelt - NASA selected twoproposals from researchers at NASA's Goddard Space Flight Center in Greenbelt, Md., to assist with measurements the agency's LunarReconnaissance Orbiter will make. LRO, is being built and managed by Goddard and is scheduled for launch later this year.

LRO represents NASA's first step in its plans to return humans to the moonby 2020. The orbiter will conduct a one-year primary mission exploring the moon,taking measurements to identify future robotic and human landing sites. In addition, it will study lunar resources and how the moon's environment will affect humans.

The launch of LRO also will involve a second spacecraft called the Lunar Crater Observation and Sensing Satellite, or LCROSS, which will impact a permanently shadowed crater near a lunar pole to search forevidence of polar water ice. One of the Goddard proposals will investigate whether electrically charged dust is propelled across the moon by electric fields on the lunarsurface ahead of Terminator Sweep.

The other proposal will aid in the search for hydrogen andwater ice deposits in the permanently-shadowed craters of the lunar poles. The dust investigation, "Mapping Lunar Surface Electric Fields andCharacterizing the Exospheric Dust Environment," is led by Dr. Timothy Stubbs, a researcher with the University of Maryland, Baltimore County, who is contracted to Goddard.

The water ice investigation, "Enhancement of Lunar Exploration Neutron Detector Mission Operations and Science Return,"is led by Dr. Timothy McClanahan of NASA Goddard.

"From the experiences of the astronauts during the Apollo program, lunar dust is recognized to be a significant nuisance, and potential hazard, to robotic and human exploration," said Stubbs.

"These dust problems were likely exacerbated by electrostatic processes, so it isimportant to understand lunar surface and dust charging to developeffective mitigation strategies." The dust investigation will determine how much lunar dust is electrostatically transported above the moon's surface and create maps of electric fields on the lunar surface to help predict when and where this dust transport is likely to be most active.

The investigation will characterize the high altitude lunar dust"atmosphere" using dust strikes detected by LRO's Cosmic Ray Telescope for the Effects of Radiation instrument. The investigation also will evaluate the amount of lunar dust above the surface of the moon by using the Lunar Reconnaissance Orbiter Camera, known as LROC, and Lyman-Alpha Mapping Project imagers to view a glow on the lunar horizon that is thought to becaused by sunlight scattered by dust particles. It will map the lunarsurface electric fields using surface charging models together with topographic and shadowing data from LROC and the spacecraft's Lunar Orbiter Laser Altimeter instrument.

Inputs to the computer models that estimate electric charging on the lunar surface will come from spacecraft that are measuring the plasma and energetic particles upstream of the moon and from observations of the incoming solar ultraviolet and soft X-ray radiation. The hydrogen and water ice investigation is similar to a treasure hunt."It costs tens of thousands of dollars per pound to put materials into space," said McClanahan. "That makes ordinary water on the moon more precious than gold. To make lunar exploration affordable, we need to use the resources of the moon as much as possible, so we can avoid the cost of bringing them up from Earth."

With little to no atmosphere, most of the moon is drier than the driest terrestrial desert. However, there may be concentrations of hydrogen, a component of water, and even some water ice at the bottom of craters in the lunar poles. The depths of some craters in the polar regions are inpermanent shadow. Very cold, small swipes of terrain are never exposed to direct sunlight. In these conditions, hydrogen and possibly water ice is thought to have accumulated over billions of years. Some scientists believe water vapor from past comet impacts has migrated across the lunar surface to the poles to become embedded in the soil at the bottom of these dark craters.

Others believe hydrogen, a primary component of the solar wind, has become embedded in the lunar soil in these polar cold traps over time. If water ice exists in the eternal shadows of the lunar poles, and itis practical to extract it from the soil, the water could be broken down into hydrogen and oxygen for use as rocket fuel and breathable air. Even sufficient concentrations of hydrogen by itself would be valuable because hydrogen could be used as fuel or combined explosively with oxygen from the soil to make water.

The investigation will use the presence of hydrogen as a sign of potential ice deposits. The moon is constantly being hit by cosmic rays, particles moving at almost the speed of light that come from explosions on the sun and in space. These particles hit the lunar soil and, like the break at the start of a pool game, create a shower of other particles. Neutrons, a component of the nucleus of atoms, are among these particles, and some fly back out into space. These neutrons can be detected by LRO's Lunar Exploration Neutron Detector, also known as LEND.

The neutrons have a wide range of speeds. If the neutrons hit hydrogen atoms in the lunar soil before being ejected intospace, the impact will slow them down. As LRO scans the lunar surface, LEND counts the neutrons moving at speeds in the middle of the range. If LEND detects a decrease in the amount of neutrons moving at mid-range speeds, it means the neutrons are being slowed by impacts with hydrogen, so there is probably a concentration of hydrogen or even water ice in that particular area.

"The Lunar Prospector mission created rough maps of hydrogen concentrations based on this decrease in neutron speed," said McClanahan."LRO will create maps with much greater detail, which is needed to make the search for hydrogen deposits practical." McClanahan's investigation will help LRO scientists interpret what they are seeing from the LEND instrument by creating computer models of how the data will appear based on different temperatures, soil compositions, and levels of cosmic radiation.

NASA received a total of 55 proposals in response to a NASA Research Announcement released in 2007. A peer review panel and NASA Planetary Science Division Research and Analysis Program scientists evaluated the proposals, from which 24 investigations were selected.

Selection criteriaincluded intrinsic merit, relevance, responsiveness to planetary science goals and objectives, as well as cost. Scientists will be fully or partially funded depending on their research work and scope of activities. Both Goddard proposals are fully funded by NASA.

For a complete list of the selected scientists and their investigations, visit: http://www.nasa.gov/pdf/216482main_LRO_Participating_Scientists.pdf

For images, visit: http://www.nasa.gov/centers/goddard/news/topstory/2008/lro_awards_release.html

Prof looks for water in unlikely place

Nick Bakshi
The Brown Daily Herald

Thirty-seven years ago, Apollo 15 brought back 170 pounds of surface material from its lunar mission. But recently a Brown professor found something unexpected in the samples - water.

In a presentation to the 38th Lunar and Planetary Science Conference earlier this month, Assistant Professor of Geological Sciences Alberto Saal announced his discovery of trace amounts of water - about 30 parts per million - in a sample of basalt recovered by the 1971 Apollo 15 mission.

To date, no one had found any conclusive evidence of water in the samples.

"They thought it was stupid," Saal said of his proposal to reexamine the basalt. "It took me three years to get it funded."

Saal said the advantage he had over previous examiners was a technique created by Erik Hauri, a researcher at the Carnegie Institution for Science's Department of Terrestrial Magnetism. The new technique allowed Saal to achieve a level of precision that was not possible for previous researchers.

Saal said that with the older technology, it had been difficult to differentiate the planetary component of the sample from terrestrial contamination. But with Hauri's new method, Saal was able to examine the basalt with as much as two orders of magnitude more precision.

The basalt isn't exactly dripping with water, but the discovery provides support for one theory on how the moon came to exist.

"In some sense, it's expected," said Ian Dell'Antonio, associate professor of physics. He explained that the water, based on beads of glass brought from the moon's core to its surface by volcanic eruptions, helps to explain the creation of the moon by providing evidence on the composition of its core. He said the discovery verifies the common theory that the moon was created more than 4 billion years ago when an object the size of Mars impacted the Earth.

Dell'Antonio added that, while this verifies one theory about the existence of water on the moon, it does very little for another, more controversial theory that postulates impacting meteroids posited water in the form of ice on the surface of the moon after its creation.

According to NASA's National Space Science Data Center, it is in this second type of water - surface ice embedded in craters situated at the moon's north and south poles - that future exploration would look for.

"Deposits of ice on the Moon would have many practical aspects for future manned lunar exploration," the Web site states, citing the ice as a possible source of water and oxygen for future explorers.

After attempts by the Clementine probe in 1994 and the Lunar Prospector in 1998 to discover such surface ice on the moon, NASA plan to launch another craft, the Lunar Reconnaissance Orbiter, equipped with new technology, to continue the search in October.

This Reborn Passion for the Moon

Some preliminary thoughts have come to mind, admittedly from quite a distance from the 3rd Space Exploration Conference in Denver, about Goldstone's radar survey and what NASA has revealed today about the region inside 5 degrees of the Lunar South Pole, particularly what we now appear to know with increased certainty about the elevations and general topography of that historic region.

It may be a little difficult to think of a previously obscure and unvisited spot in the Earth-Moon system as historic. Perhaps we should think of the Prospector impact point as essential to "Future-History," and no longer the realm of Science Fiction masters like Robert Heinlein.

Long ago, back in 1999 when Prospector and its neutron spectrometer showed a definitive signature of Hydrogen around the lunar poles no one was more tickled than I. Some of us have been literally anxious for a reawakening of interest in our Moon since December 1972 and the bittersweet success of Apollo 17. A possible presence of water slurry somewhere on the Moon might be just the thing, and indeed it has been, cinching the deal and making our return inevitable whether those, perhaps not so ancient, cometary remnants prove to amount to much or not, and quite possibly with or without the leave of governments and taxpayers.

Since then, it's been shown water can be refined from the lunar surface and perhaps just about anywhere on the Moon. The obvious positioning of our relatively large natural satellite as a kind of pier, a site for rail guns and materials and astronomy, with no ecological worries, no EIS responsibilities and all the rest some of us deducted and lobbied for over the past 35 years is more generally known then ever before or since.

It's a relief, really, no longer having to have to explain these things, over and over. And if you can give credit to such simple probes as Clementine and Prospector, catalysed by the horror of Columbia tearing the cover off the rudderless administrative inertia of NASA, so much the better.

In 1999 the presence of water on the moon, I believed. would be the Discovery of the Year, and I still do. The object at rest has been set into motion, harder now to stop than it was to start.

One way to tell how very much interest in space exploration has grown in the short time since is how the news of that "discovery" was received in 1999 and then to speculate on how such news would be received today. I suppose it's a chicken and the egg thing, possibly, whether the "Vision" following Columbia or the possible detection of water or something else entirely has stimulated this passion for the Moon, we've been waiting for these radar studies and the passion for the challenge of a return to the Moon, for plain and practical reasons and by all sorts of people for a long, long time.

In 1999, no one was discussing traffic control problems in lunar orbit or how to set that first flag back up at Tranquillity Base, according to Edwin Aldrin blown over by the Apollo 11 Lunar Module ascent stage - without disturbing those first foot prints. In 2008, were already counting the months until the next probe, the first private probe, the next nation's manned return and where and when the United States will return to this new world, this time to stay.

Once again, "the clock has started."

Nevertheless, with these new radar studies showing us 100 fold clearer detail of a part of the Earth - Moon system never before seen, the Lunar South Pole is better known by the space community than ever before.