- :: Atom & Cosmos
- :: Body & Brain
- :: Earth
- :: Environment
- :: Genes & Cells
- :: Humans
- :: Life
- :: Matter & Energy
- :: Molecules
- :: Science & Society
- :: Other Topics
- :: Science News For Kids
Text Size
The one-two punch of crashing a booster rocket and its mother craft near the moon's south pole didn’t kick up dramatic and visible plumes as hoped, but scientists reported October 9 that the mission had gathered enough data to tell whether the crater contains frozen water.
At 7:31 a.m. EDT on October 9, an empty rocket booster was deliberately crashed into Cabeus, 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. No plumes were visible. 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.
About four minutes after the first crash, LCROSS took its own death plunge into the crater. Even without a visible plume to ooh and aah over, the data recorded by LCROSS as it homed in on Cabeus 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. Cohen was 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.
LCROSS detected a small rise in the amount of infrared light coming from the crater, a sign that it had seen the thermal flash from its spent rocket boost. LCROSS also confirmed that the crater had brightened at both infrared and visible wavelengths. The brightening indicates the booster's crash had kicked up material.
The spacecraft also recorded variations in the intensity of visible and ultraviolet light, said Anthony Colaprete, LCROSS principal investigator and project scientist at NASA Ames, during a 10 am press conferences from the NASA Ames Research Center in Mountain View, Calif. “I’m excited that we saw variations in the spectra,” he said.” The information is there, we just have to get to it.”
“We have a tremendous amount of data” to analyze and piece together, added Jennifer Heldmann, also of NASA Ames and coordinator for the LCROSS observation campaign, also during the press conference.
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.
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 was deliberately crashed into the unlit side of the moon in June, a 4-meter ground-based-telescope could see it. The LCROSS rocket booster weighed about two tons and might have made a smaller impact than the three-ton Kaguya did.
A newly installed camera and a revived spectrograph on the Hubble Space Telescope observed the moon just before LCROSS and its rocket struck. Looking at the southern limb of the moon, Hubble’s Wide Field Camera 3 saw no sign of lunar material kicked up into view by the crashes, NASA announced late on October 9. A preliminary analysis of ultraviolet spectra taken by the Space Telescope Imaging Spectrograph showed no obvious sign of hydroxyl (OH), a fragment of water that might be expected to be produced if frozen water were vaporized by the impacts, said Alex Storrs of Towson University in Baltimore.
“I think if we see anything [in the images] it will be awfully subtle,” says Ray Villard, public affairs manager at the Space Telescope Science Institute in Baltimore.
During the impact event, Michael Kelley of the University of Maryland in College Park and David Harker of the University of California San Diego observed the moon with NASA’s Infrared Telescope Facility atop Hawaii’s Mauna Kea.
“The data we took is great, but we can't yet say if we saw any plume,” says Kelley. “It isn't so much disappointing as it is puzzling” why the lunar soil that must have been kicked up by the crashes wasn’t immediately obvious, he adds. “We have a lot of work ahead of us to see what happened.”
Found in: Atom & Cosmos
 |
|
 |
The technology of the Saturn program and its successor, Nova, has, seemingly, been lost. That is unfortunate, as Nova was the only reasonable way that man could have reached and returned from Mars.
The throw weight of Nova was enough for the mission and had not President Nixon killed the project, we would have already been there and returned safely.
There will not be Moon bases or more fanciful Mars bases until man is once again capable of using massive rocketry with huge throw weights. Just imagine the weight of a simple water recovery machine or of a rocket fuel production unit.
Astronomers, both professional and amateur, who were charged up to keep an eye out for it know perfectly well that a null result of a visible plume is also important.
But if NASA keeps playing that obnoxious hype card in their feverish attempts to be "hip" in their "public outreach" efforts, they'll inevitably see as many "bombs" as Hollywood routinely does. Hollywood marketing practices are NOT a good model for informing the public about science. Come to think of it, Hollywood-type marketing practices aren't very good at energizing (let alone informing) the public in a way that boosts ticket-counter sales either.
Unfortunately, while Hollywood can easily absorb the impact of its "bombs", NASA has no similar shield to protect it from the relentlessly cynical gabbing of media pundits who enjoy nothing more than to tear down what is good for the country and the whole world - in this case one government agency dedicated to scientific discovery that has enlarged our perspective of the universe we live in more than any other.
As a nation, methinks we pay WAY too much attention to tv. And movies. And talk radio. Where do we get any sense of what we are actually discovering, what we actually know? If that information isn't supplied by science and any semblance of journalistic integrity, where is it going to come from? From "Jesus"?
Consider: The pre-mission visualization video circulated by NASA shows a brilliant white ejecta cone rising from the impact.
It also shows us the Centaur rocket, a good marker of scale ...if you happen to be a rocket scientist.
But it proved no clue at all to the general public, who never found out that a Centaur is roughly 40 feet tall and 10 feet in diameter; that the plume as shown is thus perhaps 400 feet high and wide; and that the subtended angle of a plume 400 feet across from 248,000 miles away is a scant 0.0000175 degrees, about 1/28,000th the width of the lunar disc.
Neither was the public briefed to expect that the total explosive yield of the 6,000-pound impact would be less than that of a large car bomb. They weren't told that the Sun angle from Earth would hinder the side-lighting needed to see a dust plume, or that the rocket's large (150 square-foot minimum) impact point and beercan-like construction would muffle the impact itself.
The public weren't told any of this because Public Relations people today regard numbers and quantities as blemishes on press releases, as do most journalists; any hard specifics beyond a time, a date and a few names detract from "the story". A modern press release aims to convey an emotional, not rational message: rocket hitting the moon equals kegger-slash-telescope-party opportunity, end of story.
Occasionally this softened Pablum boomerangs on you, like it did this week. Depressingly, it usually serves nicely.
[Link was removed]
[Link was removed]
[Link was removed]
[Link was removed]
[Link was removed]
[Link was removed]
[Link was removed]
[Link was removed]
[Link was removed]
[Link was removed]
[Link was removed]
Please login or register to participate.