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Water MAY be found with Bigger Shovels!

Lunar CRater Observation and Sensing Satellite (LCROSS)

Is there water on the Moon? Enough to borrow for a drink?

Are we going to have to get some hydrogen and some oxygen and burn them to make a drink?

Where we build a Moon Base on our way to Mars may be dependent on what we can find to use "off the land" on the Moon. One thing we need to find is water. So what do we know about water on the Moon?

http://history.nasa.gov/SP-350/ch-15-2.html

This site is excellent. We do not easily give up hope of finding native materials for a drink.

We already "know" there is so little water on the Moon it makes any water we can find there, where ever we can find it -- a great place to consider building a Moon Base.

In fact, if you want any water to be found on the Moon, it is a virtual point of desperation. The missions to "find out" if we can get a drink on the moon are indeed finely focused and nearly single minded, with that goal of either finding or not finding water the determinant of where a permanent lunar abode might be built.

The only marginally realistic hope for water, or for easy hydrogen in quantities to use for making water, is looking in the dark shadow shaded areas near the lunar poles.

(And it is, in my opinion, a pretty slim hope. Of course, I hope there are cubic kilometers of water ice, or hope even for a few hundred acre feet. . or a few acre feet!) But, this water search-thing is something that absolutely must be done.

Now, we know that the Clementine radar observations and Lunar Prospector neutron spectroscopy results suggest water ice, a potential resource, is to be found in shadowed craters near the lunar poles. Since these observations are by no means conclusive, we have to take a look.

Yup! We need to determine whether or not ice exists in significant quantities at the lunar poles to decide if that is the place to build our hotel! (Or motel.)

We do this with a kind of shovel. And we do this on the cheap (relatively), not that anything to do with NASA is cheap. As they say, This IS Rocket Science.So it does have some theory support, which I mention at the bottom of this posting: The Lunar Theory of Water in Dusty Shadows.

To "probe" the lunar regolith (surface rocks and dust) in the permanent shadow two massive hammers acting like "shovels" will 'smack' the Moon hard enough to kick up some real amount of material -- ten schoolbus loads -- and pitch it into a cloud above the lunar surface.

The purpose of the impactors, is like shovels. That is, to excavate craters to raise dust and release any "volatiles" contained in the dust into a "plume" observable primarily by the Shepherding Spacecraft (S-S/C)following right behind the first impactor, as well as a bevy of sophisticated Earth-based, aerial and orbitals telescope assets.

The Shepherding Spacecraft "becomes" the follow-on impactor after it transmits its data about the first impact! Then it 'bites" the dust in a glory moment!, observed by the Lunar Reconnaissance Orbiter and maybe even amateurs here on Earth, and for amateurs it is within reach!

(Folks, if we find water in quantitiy on the Moon, the effort in going to the Moon and building a base is simplified!)

It would be like not having to fly in all the energy fuel at the South Pole[Amundsen-Scott Station] Earth Pole Station, The Amundsen Scott station on Antarctica! Not that we can't. It just makes it expensive.

With the LCROSS mission, the idea is to loft tons of the lunar materials, from the Moon's sub-surface to be observed with ground-based, aerial, and orbital telescopes. Models of the impactors intimate that the some of the "plume" materials should be lofted as much 50 km (30 miles) into space. It will form a cloud. It will rise and expand, propelled at 250 meters per second initially.

The surface brightness of the dust-with ice cloud will increases as the cloud ejecta expands, and in 40 seconds, this ejecta cloud should fill a 1-arc-second observing area as seen from Earth-based telescopes.

The water molecules, if any, will be dissociated by solar UV radiation and the OH molecule will be observable in emission at 308nm. Moderate-sized (6 to 8-inch, and larger) amateur telescopes can see the 40-second plume growing to 1-arc-second size.

Images NASA

Observe the LCROSS impacts!

Date & Time:
Projected lunar impact is on October 9, 2009 at 11:30 UT (7:30 a.m. EDT, 4:30 a.m. PDT), +/- 30 minutes.

The impact time will be refined as the mission progresses. Two weeks prior to impact, the impact time will be known to within a second.
Check back on this webpage for the most up-to-date timing information.

Location:
LCROSS will impact at the south pole of the Moon. The final site selection will be made 30 days prior to impact.

Check back on this webpage for the most up-to-date impact location information: lcross.arc.nasa.gov/observation.htm

These are graphic suggesting the anticipated impact.
(ALL IMAGES NASA)

Continuously monitoring the impact events at a variety of spatial and temporal scales will allow us to understand lunar impact processes and to assess the likelihood that water ice exists, and how much exists within the permanently shadowed target crater.

The predicted ejected mass following the LCROSS Centaur impact is approximately 230 times larger than that predicted for Lunar Prospector (LP).

Water ice in the ejected dust cloud will sublime (convert to a gaseous state) under the influence of solar irradiation. The rate of this sublimation depends primarily on the water to ice ratio and particle size, with ~0.1 mm dust rich (1% water ice) particles subliming their water in several minutes. (Observations will time this sublimation (if any.))

The launch and impact schedule is not set yet. Launch is sometime in 2008! Hammer down in 2009. (Amateurs, take your telescope to the southern latitudes of the US for warmth.) Though both lunar poles have shadowed areas the bigger shadow areas are on the south pole, so that is probably  where it is coming down.

Moon's North Pole composite ---------------------- Moon's South Pole composite

Images: NASA

Images Above: The dark blue and purple areas at the moons poles indicate neutron emissions that are consistent with hydrogen-rich deposits covered by dessicated regolith. These hydrogen signatures are possible indications of water in the form of ice or hydrated minerals. Feldman et al., Science, 281, 1496, 1998.  Credit: NASA

Just like on Earth, water will be a crucial resource on the moon. Transporting water and other goods from Earth to the moon’s surface is expensive. Finding natural resources, such as water ice, on the moon, could help expedite lunar exploration. The LCROSS mission will search for water, using information learned from the Clementine and Lunar Prospector missions.

The LCROSS mission also provides us ready technologies and modular, reconfigurable subsystems that can be used to support future missions and architectures, possibly another hammer approach -- if success at detection of water is made. IF we find water, you might want to check the Moon's north polar areas too, and you just have to load the package aboard another launch vehicle and send it again, targeting the shadows on the other pole.

Ames Research Center (ARC) is overseeing the development of the LCROSS mission with its spacecraft and integration partner Northrop-Grumman. This is a fast-paced, low-cost, mission that will leverage some existing NASA systems, Northrop-Grumman spacecraft expertise, and Ames’ Lunar Prospector experience. Ames is managing the mission, performing mission operations, and is developing the payload instruments, while Northrop Grumman is designing and building the spacecraft for this innovative mission.

Scheduled for launch in 2008, LCROSS will travel to the Moon as a co-manifested payload aboard the launch vehicle for the Lunar Reconnaissance Orbiter (LRO). LRO is designed to map the lunar surface and characterize landing sites for future missions, but only is funded for about a year.

Even negative results are informative! That is how Science is done! Yes, there is a yellow part, see my comments at the end of this post.

The Lunar Theory of Water in Dusty Shadows:

One of the whispers of "hope" for some quantity of water on the Moon comes from theory. And the greatness of theoretical approaches is in figuring out how things are and then getting the ground truth to validate the supposition!

"Image above: At the moon's poles, the Sun rises no more than 1.6 degrees above the horizon because that is how much the moon is tilted on its axis, therefore relatively shallow craters can have permanently shadowed floors where water ice can exist. The moon has practically no atmosphere. Any light elements or compounds deposited on the lunar surface by possible out-gassing or comet fragments and meteorites are subject to direct exposure to the vacuum of space. Over the course of a lunar day, about 29 Earth days, all exposed surfaces of the moon are bathed in sunlight with daylight temperatures reaching up to 250° Fahrenheit (121° C.) Any ice exposed to sunlight for any length of time would turn into water vapor, break apart and be lost to space.

Water could only exist in areas of permanent shadow and those areas exist at the lunar poles. Some of these crater floors have not seen sunlight for possibly billions of years. Temperatures within these crates do not go above –280° F (-173° C) so they act as ‘cold traps’ where even light elements or compounds don’t have enough energy to evaporate" -- NASA

"Dana Hurley Crider & Richard R. Vondrak in a detailed study published in the Journal of Geophysical Research, "Space weathering effects on lunar cold trap deposits", JGR 108, 3845-3862, 2003 simulate the evolution of a H2O column in a lunar cold trap over time as a function of depth with H2O arriving from both the solar wind and from comets.

Crider and Vondrak conclude that the regolith would reach an equilibrium
concentration of H2O at 4100 ppm (0.41% per unit mass). This
equilibrium value would be reached from solar sources alone and
comets essentially are superfluous. Time merely increases the
thickness of the layer in which ice will be harbored. In 1 billion years
the layer would be 1.6 m thick. The ice would be diffuse.
- Their results are consistent with Arecibo observations and within a
factor-of-2 Lunar Prospector neutron spectrometer values".--NASA

This is not a highspeed vaporization causing impact, since the velocities are only a little more thant the projectile of an M1-A1 battle tank, projectiles of which travel a little over a mile a second. These shovels will go a little faster, than the tank projectiles, but less than 6000 feet a second, according to the orbital physics published.

With the impacts of the Centaur and Shepherding Spacecraft occurring within a permanently-shadowed crater near one of the lunar poles, the impacts themselves will be obscured by the crater rim as seen from Earth and Earth orbit. However, ground-based and orbital observatories will observe the dust and water vapor plume caused by the two impacts into the lunar surface. The impact ejecta cloud should be in view of Earth assets just several seconds after impact and will peak in brightness around 30-100 seconds after impact.

The timing of the two impacts will allow simultaneous observations from Hawaii (NASA-IRTF, NASA-Keck, Gemini-N, Subaru, CFHT), the Continental US (Kitt Peak), and from South America (Gemini-S, VLT-ESO in Chile). Compared to the Deep Impact (DI) Mission encounter with comet 9P/Tempel, LCROSS’s Centaur impact plume will have 100 times less mass at 360 times closer range, so the surface brightness will be higher. However, the dust-to-ice ratio for targeted regolith is expected to be 100 in comparison to ~0.5 for Deep Impact. Therefore, ground-based telescopes will observe the thermal evolution of and the properties of the dust in the ejecta plume, and 8-10 m class telescopes, e.g., NASA-Keck+NIRSPEC, will be required to search for water vapor using the non-resonant fluorescent lines at ~3 µm. The longer time scale evolution of the OH exosphere can be followed by telescopes in Spain (Calar Alto), the Canary Islands (Mount Teide), and Australia (Siding Springs, Mt. Stromlo). Orbital assets such as SWAS, HST, NASA’s Galaxy Exploration Explorer, and the Far Ultraviolet Spectroscopic Explorer (FUSE) may also be used to observe the impact plume. The idea is to capitalize on the experience gained during the DI observation campaign by members of the science team and other DI participating scientists who are advising the project. The Observation Campaign Manager is responsible for the coordination of the ground-based observing campaign. The more observations, the better the answers.

UPDATE!

Image: NASA from the Lunar Prospector.  The percentage means a better chance for finding water.

Zoomed in image of south pole Potential Water Concentrations based on data from Lunar Prospector. The blues and purples indicate the highest potential of water ice.

WHAT WILL IT LOOK LIKE?

Composite image of the South Pole taken by New Mexico State University/ Marshall Space Flight Center, using the Tortugas 24” telescope.
Credit: NMSU/MSFC

IT is going to take some study to find this in your back yard telescope!

Labeled composite image of the South Pole taken by New Mexico State University/ Marshall Space Flight Center, using the Tortugas 24” telescope.
Credit: NMSU/MSFC

Amateur Observations and Notes form the Nasa LCROSS website.

http://lcross.arc.nasa.gov

The Centaur impact plume should be visible through amateur-class telescopes. As the mission progresses, this site will provide the general public, classrooms, and the amateur astronomy community details on how to observe the impact. The LCROSS mission will actively solicit images of the impact from the public. These images will provide a valuable addition to the archive of data chronicling the impact and its aftermath. This site will include a gallery of images received from both the public and professional communities.

My  "Hopes" for the Mission!

I hope the impacts are sufficient to jar the heck out of enough dust, and that it is "thick and deep enough" to have accumulated the hydrogen or H2O ice to be lofted into the space above the impacts to show us something, either way.  I do not think we will find enough water to write home about -- but any quantity above practically zero will be encouraging.  Hope.

The nightmare scenario for me (and probably our sensible NASA scientists) is this: What if both the impacts in shadow strike (impact) hard, consolidated rock faces with no significant amounts of subsurface dust or regolith to shovel into the space where all the instruments will be looking? That is, what if we do not get deep enough into the surface where all this ice, or hydrogen is supposed to be locked in the shadows? Likely a negative negative, which does not make a positive.

Hope for favorable ground truth! Water. Cold. Clear. Sweet. .

=========news Change of Target:

http://www.nasa.gov/mission_pages/LCROSS/main/index.html

NASA's Lunar Crater Observation and Sensing Satellite mission (LCROSS) based on new analysis of available lunar data, has shifted the target crater from Cabeus A to Cabeus (proper).

www.nasa.gov/centers/ames/news/features/2009/LCROSS_new_crater.html

On the image -- that is SP_C

Good luck!