London, October 16 (ANI): Reports indicate that the NASA's LCROSS moon-smashing mission might have been doomed from the beginning, as some scientists involved with the mission were predicting very little, if anything, would be seen from the impact, despite a well publicized observing campaign.
According to a report in New Scientist, LCROSS ended today morning when a two-tonne Centaur rocket hit the floor of a perpetually shadowed crater near the lunar south pole, in an attempt to extract water.
Scientists hoped that dust and vapour kicked up by the impact would climb high enough to catch sunlight, allowing a satellite that trailed behind the rocket to hunt for traces of lunar water in the ejected debris.
The Hubble Space Telescope and many Earth-based observers were recruited to watch for a plume of debris rising from the impact site.
But while scientists voiced disappointment when no obvious plume was spotted from any vantage point, some were not surprised.
"We had a meeting in August where we reported what we thought would be the scenario," said LCROSS team member Peter Schultz of Brown University.
He said that the new estimate for the mass that would be lofted to a visible elevation was 100 to 1000 times lower than estimates that had originally informed the mission.
Schultz and his team derived their numbers from projectile experiments using a high-speed vertical gun at NASA.
Their results differed strikingly from models that assumed debris would fly outward from the impact site a 45 degrees angle.
Instead, the team found that the fastest debris, ejected at the initial stages of crater formation, tended to depart at an angle closer to 30 degrees more of a sideways spray than an upward trajectory.
Another potential problem is that the 10 metre-long rocket was expected to produce a crater only 20 to 30 m in diameter.
That crater size is small enough for the shape and orientation of the rocket to have played a role in how the debris was ejected, confounding expectations.
"Under those circumstances, the usual scaling relations may not have applied as well as we thought, even though we tried to take that into account," said LCROSS team member Don Korycansky of the University of California, Santa Cruz.
According to Paul Spudis of the Lunar and Planetary Institute in Houston, Texas, a positive detection of water would not provide any information about the extent and distribution of ice on the moon's surface, which is the point of looking in the first place.
"That tells me the fundamental rationale behind the mission was flawed," he said. (ANI)