Despite the disappointing lack of a visible debris plume, NASA scientists say they have the data they need to figure out if there's water on the moon after their space probe crashed into a lunar crater.
Tthe first half of the Lunar Crater Observation and Sensing Satellite, known as LCROSS, slammed into a deep and permanently dark crater on the south pole of the moon. Soon after that initial crash, the second half of the spacecraft, which had separated into two pieces last night, hurtled through the kicked up debris, grabbing data about the matter, and then it too crashed into the crater.
It's a double whammy that NASA hopes can help it determine whether there is water on the moon. NASA is still hopeful to one day create a viable human outpost on the moon, a goal that would benefit greatly from a discovery of water on the moon. It would be far cheaper and easier to drill water on the moon than have to haul it up from Earth.
"We have the data we needed to address the question of water," said Anthony Colaprete, the LCROSS principal investigator for NASA. "The science team will analyse the data. We just have to sit back and be careful. We don't want to make a false negative or a false positive claim. We saw something and that's heartening. We're going to take our time and build up a case for water."
While NASA "saw something," fans of space exploration didn't see what they had expected this morning. NASA had been promising live images of the impact and resulting debris plume but images on NASA TV were live only until moments before impact when it turned to black.
Some have questioned whether the crashes even caused a debris plume and whether any helpful data will result from the experiment.
Colaprete noted that the images streamed out for video were not what the second half of the spacecraft would have detected as it flew its own path into the crater.
"I knew we were going someplace where you expect the unexpected," he said, adding that scientists did record a spectra, or light waves, after the crash. "I'm not convinced we haven't seen ejecta. Stay tuned. I certainly hope we can dig something out of there that will be telling."
Faith Vilas, director of the MMT Observatory in Arizona, said the observatory's telescope was focused on the lunar crater during the crash and did not detect a debris plume. She added, though, that the plume could have occurred nonetheless.
"We didn't see a thing. We didn't see any obvious sign of an impact," said Vilas. "In choosing this crater for impact, the spacecraft went 2 kilometers deep so a lot of the plume would have been shielded from view by crater walls."
S. Pete Worden, center director at NASA's Ames Research Center, said it had been an exciting morning. "LCROSS showed that low cost, innovative missions can excite the public and do good science," he added. "It expands and continues our exploration into the solar system."
The LCROSS spacecraft, which blasted off from Cape Canaveral Air Force Station in Florida on 18 June, went aloft with its companion satellite, the Lunar Reconnaissance Orbiter. As the Atlas V rocket that carried them lifted off, a NASA spokesman called it "NASA's first step in a lasting return to the moon."
The Lunar Reconnaissance Orbiter, which has been in orbit around the moon since late June, was 50 kilometers above the moon's surface during this morning's impact. The orbiter is expected to send its own analysis of the debris plume back.
The LCROSS spacecraft, aside from being a projectile, was a vehicle heavily loaded with scientific gear. According to NASA, its payload consisted of two near infrared spectrometers, a visible light spectrometer, two mid infrared cameras, two near infrared cameras, a visible camera and a visible radiometer. The instruments were selected to provide mission scientists with multiple views of the debris created by the hull's initial impact.