Moon CrashA planned one-two punch into the moon to search for hidden reserves of frozen water seemed to have gone off like clockwork. But if the crash kicked up plumes of lunar soil into the sunlight, the plumes weren’t as visible as researchers had hoped.At 7:31 a.m. EDT on October 9, an empty rocket booster was deliberately crashed into Caebus, a shadowed crater near the moon’s south pole where ice is suspected to reside. Astronomers watched through telescopes and the visible-light camera aboard the rocket’s mother ship, NASA’s LCROSS, or Lunar Crater Observation and Sensing Satellite, spacecraft. Amateur astronomers using medium-sized backyard telescopes have not reported seeing a plume, which had been predicted to rise above the crater rim and be visible from Earth. “It’s hard to tell what we saw there,” commented Michael Bicay as he watched the crash from the NASA Ames Research Center in Mountain View, Calif., where he is science director. About four minutes later, just before taking its own death plunge into the same crater, LCROSS did confirm that the crater had brightened at both infrared and visible wavelengths.
The brightening indicated the booster's crash had kicked up material, although no actual plume was recorded by the LCROSS visible-light camera. “It’s a little disappointing,” said planetary scientist Bill Hartmann of the Planetary Science Institute in Tucson, one of about 200 astronomers in Fajardo, Puerto Rico, attending the annual meeting of the American Astronomical Society’s Division for Planetary Sciences and who gathered together to view the LCROSS images on a big screen. “It would have been nice to see something,” he added.
But even without a visible plume to ooh and aah over, the data recorded by LCROSS as it homed in on Caebus and flew through the debris from the first impact will still be invaluable for searching for frozen water, said Barbara Cohen of the lunar precursor robotics program at NASA’s Marshall Space Flight Center in Huntsville, Ala.Astronomers are scrutinizing the data as well as that taken from a slew of other telescopes, including the Keck Observatory atop Hawaii’s Mauna Kea, to look for the fingerprints of water vapor or for one of its fragments, the hydroxyl radical, which contains one oxygen and one hydrogen.
But even without a visible plume to ooh and aah over, the data recorded by LCROSS as it homed in on Caebus and flew through the debris from the first impact will still be invaluable for searching for frozen water, said Barbara Cohen of the lunar precursor robotics program at NASA’s Marshall Space Flight Center in Huntsville, Ala.Astronomers are scrutinizing the data as well as that taken from a slew of other telescopes, including the Keck Observatory atop Hawaii’s Mauna Kea, to look for the fingerprints of water vapor or for one of its fragments, the hydroxyl radical, which contains one oxygen and one hydrogen.
The presence of either fingerprints or fragments would indicate that the part of the crater floor impacted indeed contained ice.
Keck astronomers did see a brightening in the spectroscopic readings, indicating that Keck recorded the plume. The astronomers will not know about water vapor, as that data will take a little longer to analyze.
More details are expected after a 10 a.m. EDT press briefing from NASA Ames, the control site for the LCROSS mission.
Astronomers using the 5-meter Hale Telescope at Palomar Observatory near San Diego also saw no plume. By comparison, when the Japan Space Agency’s lunar-orbiting Kaguya spacecraft deliberately crashed into the unlit side of the moon last June, a 4-meter ground-based-telescope could see it. LCROSS’s rocket booster weighed about two tons and might have made a smaller impact than the three-ton Kaguya did.
Keck astronomers did see a brightening in the spectroscopic readings, indicating that Keck recorded the plume. The astronomers will not know about water vapor, as that data will take a little longer to analyze.
More details are expected after a 10 a.m. EDT press briefing from NASA Ames, the control site for the LCROSS mission.
Astronomers using the 5-meter Hale Telescope at Palomar Observatory near San Diego also saw no plume. By comparison, when the Japan Space Agency’s lunar-orbiting Kaguya spacecraft deliberately crashed into the unlit side of the moon last June, a 4-meter ground-based-telescope could see it. LCROSS’s rocket booster weighed about two tons and might have made a smaller impact than the three-ton Kaguya did.
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