Lunar CRater Observation and Sensing Satellite (LCROSS) PART1
Lunar CRater Observation and Sensing Satellite (LCROSS) PART2
Lunar CRater Observation and Sensing Satellite (LCROSS) PART3
Alexis Madrigal writes: "Scientists in the post-Apollo era have been quietly revealing the secrets of our satellite and laying the groundwork for a new wave of moon missions. Their efforts have turned up tantalizing evidence that water ice exists on the moon, which would make the long-held dream of sending manned missions to other planets just a little bit easier.
"The NASA mission is only the third American trip to the moon since those famed Apollo missions of the late '60s and early '70s.
"The Lunar Crater Observation and Sensing Satellite will be live-streaming a flyby as it swings into position in orbit, where it will await instructions to plunge into a dark crater on the moon’s surface. That will throw up a plume of debris that LCROSS’ counterpart, the Lunar Reconnaissance Orbiter, will fly through, allowing it to determine whether water ice exists below the surface of the moon.
Northrop Grumman video about a NASA moon mission.
"If water ice is indeed confirmed," a NASA official explained, "it would be a major victory for post-Apollo lunar science, which has suffered from a lack of public interest since the end of manned missions.
"In general, the exploration of the moon has been driven by the manned program," said Steven Dick, NASA chief historian. "Before the Apollo program, you had the Ranger, the Surveyor and Lunar Orbiter missions, the unmanned missions. Those were all driven so that people could land there."
Now, as NASA builds the capability to go back to the moon," Madrigal writes, "unmanned missions like LCROSS are again making their way to our satellite. As they generate a new wave of interest, the importance of the missions between Apollo and the new wave could increase.
Immediately in the wake of the Apollo 11 lunar landing, the other shoe dropped on the program's funding. With the United States mired in Vietnam and burdened by a list of other expenditures, Dick said that the will to put money into lunar exploration fell away. Americans set their sights on domestic issues close to home as well as on farther-flung targets in space.
"The general consensus was 'We beat the Russians, and that's what we set out to do,'" he said.
The U.S. spent an estimated $25 billion in 1969 money on the Apollo program. That would be at least $115 billion in 2008 money and as much as $362 billion, depending on the method of calculation. (NASA's 2009 budget came in at $18.1 billion.)
The last three Apollo missions were canceled and for 22 years, no spacecraft visited the moon. Why bother? It was lifeless. It seemed impossible that water could survive. We could do a lot of lunar observations from Earth. Really, it became one of the least interesting objects in the solar system, despite its proximity.
Then, in 1994, a Department of Defense funded projected nicknamed Clementine
launched for the moon.
A low-budget affair planned as a technology demonstration, “it did not have science as a primary objective,” a National Research Council report noted. Nonetheless, the mission raised an intriguing possibility: ice on the moon.
This wasn't entirely shocking, but it was exciting. It had been suggested as far back as 1961 that water ice might exist on the moon in areas that are never exposed to sunlight. Water left over from the moon's infancy or deposited there by meteorites or comets could have just stuck around in the craters at temperatures that never rise above minus-280 degrees Fahrenheit. Now, there was some experimental evidence to suggest that there was water ice on the moon.
Though more recent observations called the original finding into question, the little mission sparked renewed interest in the moon. NASA worked up its first lunar mission in a quarter century, the Lunar Prospector, to investigate the possibility of ice, among other lunar mysteries.
The Prospector's neutron flux data returned evidence of large amounts of hydrogen, "probably" in the form "abundant water ice" To confirm the observation, at the end of the Prospector's useful life, the team attempted to crash the craft into a crater and send up a plume of debris with some water ice in it.
Unfortunately, no water ice was detected in the plume, but there were a variety of reasons that could have happened. The high-risk experiment didn’t rule out the presence of ice on the moon.
And there the science sat until President Bush started to ramp up manned solar system exploration through the Constellation Program, Madrigal writes. As with the Apollo program, robotic missions are preceding the possible return of humans to the moon in the Constellation program.
"The idea now is to go back with the unmanned missions as reconnaissance to go back to the moon with manned missions," Dick said.
Humans would need water to explore the solar system," Madrigal continues, "so the possible ice on the moon suddenly became a whole lot more interesting.
"LCROSS will release its Centaur rocket on October 9, 2009," Hadley Leggett writes, "sending the projectile hurtling at the south pole of the moon at 1.55 miles per second, about twice the speed of a bullet.
Scientists hope the impact will send up a huge plume of moon debris, possibly containing ice, vapor or traces of hydrated materials that prove the existence of water on the moon.
"Four minutes later, the rest of the spacecraft will follow the rocket's path through the cloud of lunar dust, analyzing its contents and transmitting data back to Earth before the entire spacecraft crashes into the moon's surface. NASA says the impact will generate a cloud of dust so big that we may be able to see it from Earth using an amateur telescope.
"This isn't the first time we've crashed rockets into extraterrestrial bodies to find out what's inside. In 2005, NASA's Deep Impact spacecraft sent a probe crashing into Comet Tempel 1 to study the contents of the comet's interior. A European probe called SMART-1 crashed into the moon in 2006, and Japanese scientists crashed their Kayuga probe into the moon this June. So far, none of the missions have discovered the water LCROSS is looking for."
"This mission is the culmination of a dedicated team that had a great idea," said Daniel Andrews, LCROSS project manager at Ames Research Center in a release. "And now we'll engage people around the world in looking at the moon and thinking about our next steps there."
LCROSS Mission Summary
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