Target Audience: NASA's Friday Moon Crash Offers Plenty of Opportunities for Amateur Viewing

The LCROSS probe and a spent rocket stage will each impact a lunar crater to look for frozen water there

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The astronomy community, amateurs and professionals alike, will turn its attention to the moon early tomorrow morning in the hopes of confirming the long-suspected presence of water ice trapped in permanently shadowed areas near the lunar poles (not to mention the drama of seeing two man-made objects crash into the moon). A research collaboration showed last month that water exists at very low levels across the lunar surface, but concentrated ice deposits would likely be a more accessible and abundant resource.

At 7:31 A.M. (Eastern Daylight Time), if all goes according to plan, a spent Centaur rocket stage will separate from NASA's Lunar Crater Observation and Sensing Satellite (LCROSS) and strike Cabeus, a crater near the moon's south pole. The LCROSS spacecraft itself will follow closely, flying through the Centaur's debris plume for an up-close analysis before impacting into Cabeus itself at 7:35.

But the LCROSS probe won't be the only observer tracking the impacts to see what they kick up. The Lunar Reconnaissance Orbiter (LRO), launched in June along with LCROSS, will pass overhead and take measurements of the debris plume, and the Hubble Space Telescope will be trained on the targeted region, as well. According to NASA, the larger initial plume should peak in brightness 30 to 100 seconds after the rocket stage's impact.

And across the country, numerous observatories will open their doors to allow the public access to high-power telescopes for viewing the event. The impact plumes may even be visible through amateur telescopes with apertures of around 10 inches or more, according to NASA.

Live feeds from two amateur-size scopes will be streamed over the Internet by SLOOH, a company that sells virtual access to a suite of high-powered telescopes at different sites around the globe. (For this event, the company will offer free access to two smaller telescopes in the U.S.) The larger of the two SLOOH instruments, according to a public relations representative for the company, is an 11-inch model in Arizona. That telescope will likely have a better chance to capture the plumes rising from the moon than the company's other outpost in New Hampshire, as the sun will have risen on the east coast by the time of the event.

NASA, for its part, will feature coverage of the impacts on NASA TV, including live footage obtained by the LCROSS probe before its planned demise. The space agency may also have access to views obtained by the University of Hawaii's 88-inch telescope, which is perched atop Mauna Kea, one of the best astronomical viewing locations in the world.

If the LCROSS mission indeed excavates water ice from Cabeus, it would confirm a number of indirect detections, such as that obtained by the Lunar Reconnaissance Orbiter. The LRO, like its predecessor, the Lunar Prospector, has seen abundances of hydrogen on the moon that may be indicative of vast stores of water. But Lunar Prospector, in its own well-observed 1999 impact into a shadowy south polar crater, did not turn up signs of water ice.

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