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Posted by The Real Chris on July 28, 2006, 6:02 pm
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Hello,
Will anyone earth be alive in 2008? Temperature might be over 50 C? Not much
hope of survivors.
Chris.
> http://science.nasa.gov/headlines/y2006/28jul_crashlanding.htm
>
> Crash Landing on the Moon
> NASA Science News
> July 28, 2006
>
> July 28, 2006: In 1959, a spaceship fell out of the lunar sky and hit
> the ground near the Sea of Serenity. The ship itself was shattered, but
> its mission was a success. Luna 2 from the Soviet Union had became the
> first manmade object to "land" on the Moon.
>
> This may seem hard to believe, but Luna 2 started a trend:
> Crash landing on the Moon, on purpose. Dozens of spaceships have done
> it.
>
> NASA's first kamikazes were the Rangers, built and launched in the
> early
> 1960s. Five times, these car-sized spaceships plunged into the Moon,
> cameras clicking all the way down. They captured the first detailed
> images of lunar craters, then rocks and soil, then oblivion. Data
> beamed
> back to Earth about the Moon's surface were crucial to the success of
> later Apollo missions.
>
> Even after NASA mastered soft landings, however, the crashing
> continued.
> In the late 1960s and early 70s, mission controllers routinely guided
> massive Saturn rocket boosters into the Moon to make the ground shake
> for Apollo seismometers. Crashing was much easier than orbiting, they
> discovered. The Moon's uneven gravity field tugs on satellites in
> strange ways, and without frequent course corrections, orbiters tend to
> veer into the ground. Thus the Moon became a convenient graveyard for
> old spaceships: All five of NASA's Lunar Orbiters (1966-1972), four
> Soviet Luna probes (1959-1965), two Apollo sub-satellites (1970-1971),
> Japan's Hiten spacecraft (1993) and NASA's Lunar Prospector (1999)
> ended
> up in craters of their own making.
>
> Back to the Future
>
> All this experience is about to come in handy. NASA researchers have a
> daring plan to find water on the Moon and they're going to do it
> by--you
> guessed it--crash landing. The mission's name is LCROSS, short for
> Lunar
> CRater Observation and Sensing Satellite. Team leader Tony Colaprete of
> NASA Ames explains how it's going to work:
>
> "We think there's frozen water hiding inside some of the Moon's
> permanently-shadowed craters. So we're going to hit one of those
> craters, kick up some debris, and analyze the impact plumes for signs
> of
> water."
>
> The experiment couldn't be more important. NASA is returning to the
> Moon, and when explorers get there, they'll need water. Water can be
> split into hydrogen for rocket fuel and oxygen for breathing. It can be
> mixed with moondust to make concrete, a building material. Water makes
> an excellent radiation shield, and when you get thirsty you can drink
> it. One option is to ship water directly from Earth, but that's
> expensive. A better idea would be to mine water directly from the lunar
> soil.
>
> But is it there? That's what LCROSS aims to find out.
>
> The quest begins in late 2008 when LCROSS leaves Earth tucked inside
> the
> same rocket as Lunar Reconnaissance Orbiter (LRO), a larger spacecraft
> on a scouting mission of its own. After launch, the two ships will
> split
> up and head for the Moon, LRO to orbit, LCROSS to crash.
>
> Actually, says Colaprete, "we're going to crash twice." LCROSS is a
> double spacecraft: a small, smart mothership and a big, not-so-smart
> rocket booster. The mothership is called the "Shepherding Spacecraft"
> because it shepherds the booster to the Moon. They'll travel to the
> Moon
> together, but hit separately.
>
> The booster strikes first, a savage blow transforming 2-tons of mass
> and
> 10 billion joules of kinetic energy into a blinding flash of heat and
> light. Researchers expect the impact to gouge a crater ~20 meters wide
> and throw up a plume of debris as high as 40 km.
>
> Close behind, the Shepherding Spacecraft will photograph the impact and
> then fly right through the debris plume. Onboard spectrometers can
> 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
> Colaprete.
>
> The Shepherd then begins its own death plunge. Like the old Rangers, it
> will dive toward the lunar surface, cameras clicking. Back on Earth,
> mission controllers will see the booster's glowing crater swell to fill
> the field of view--an exhilarating rush.
>
> Until the very end, the Shepherd's spectrometers will keep sniffing for
> water. "We'll be able to monitor the data stream down to 10 seconds
> before impact," says Colaprete. "And we should have enough control to
> land within 100 meters of the booster's crash site."
>
> The Shepherd is 1/3rd lighter than the booster, so its
> impact will be proportionally smaller. Nevertheless, the Shepherd will
> make its own crater and plume, adding to those of the booster.
> Astronomers hope the combined plumes will be visible from Earth,
> allowing observations to continue even after the Shepherd is destroyed.
>
> Many readers will remember the crash of Lunar Prospector in 1999.
> Mission controllers guided the ship into Shoemaker crater near the
> Moon's south pole in hopes of kicking up water - just like LCROSS. But
> no
> water was found.
>
> "LCROSS has a better chance of success," says Colaprete. For one thing,
> LCROSS delivers more than 200 times the impact energy of Lunar
> Prospector, excavating a deeper crater and throwing debris higher where
> it can be plainly seen. While Lunar Prospector's plume was observed
> only
> by telescopes on Earth a quarter-million miles away, LCROSS's plume
> will
> be analyzed by the Shepherding Spacecraft at point blank range, using
> instruments specifically designed for the purpose.
>
> Only one question remains: Where will LCROSS strike?
>
> "We haven't decided," he says. The best places are probably polar
> craters with shadowy bottoms where water deposited by comets long ago
> may have frozen and survived to the present-day. Less orthodox choices
> include canyons, rilles and lava tubes. "There are many candidates.
> We're convening a meeting of researchers to debate the merits of
> various
> sites and, finally, to pick one."
>
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