Lte's hope these "rocket scientists" realize that the moon keeps Earth in orbit... :-)

R.

Spacecraft aimed to smash moon in search for water 4.29 p.m. ET (2030 GMT) July 30, 1999

By Paul Recer, Associated Press

WASHINGTON (AP)  Speeding at 3,800 miles an hour, the Lunar Prospector spacecraft was to smash into a frigid crater of the moon early Saturday in its final task for science: a search for evidence of lunar water.

The 354-pound spacecraft was targeted to collide inside a constantly shaded crater near the moon's south pole, where scientists believe pockets of frozen water exist.

The heat and fury of the impact  equal to a two-ton car smashing into the ground at 1,100 mph  was expected to throw a cloud of vapor and debris high above the crater. An arsenal of telescopes on Earth and in space were to be watching, searching for the telltale chemical signature of water.

Lunar Prospector was launched Jan. 6, 1998, and has spent about 18 months orbiting the moon. Its five instruments have analyzed the chemistry, gravity and magnetic fields of the moon. Findings from one of the instruments led to the plan to crash the spacecraft into the surface.

The instrument detected the chemical signature of hydrogen, a finding that to scientists suggests the presence of water. By some estimates, there could be as much as 200 million metric tons of water mixed in the top 18 inches of lunar soil near the poles.

David Goldstein of the University of Texas came up with the idea of testing for the presence of water by crashing the spent Lunar Prospector into a frozen crater.

The idea was quickly approved by project scientists, but most admitted the chance of a total success is low.

"It is really a tricky maneuver,'' said David Folta, head of the NASA team controlling the guidance of Lunar Prospector.

It's like trying to hit a pie pan at home plate with a baseball thrown from second base at more than 100 miles an hour, Folta said.

The plan is for the spacecraft to fire rockets to slow down and start a speedy dive toward a crater. It will come in at a very low angle, clear a half-mile-high rim by about half a mile, then crash into the 2 1/2-mile-deep crater.

Ground controllers will not see the rockets fire, he said. The engineers will send instructions the Lunar Prospector as it circles the moon for the last time. Following the instructions, the spacecraft is to fire its rockets over the back side of the moon. It will crash before radio contact is restored with Earth.

"If the rocket burn goes as planned, we'll never see it again after it goes around the back of the moon,'' Folta said.

Alan Binder, the principal scientist for the Lunar Prospector mission, said the crash is a fitting end for the little spacecraft.

"It has never failed us,'' said Binder of Prospector's 18-month exploration of the moon. "It got 10 times more data than was expected. It has flown perfectly.''

The mission was to end Saturday anyway, and Binder said by crashing Prospector into the moon, "We'll get one final bit of science out of it.'' If all goes well, he said, the crash will produce a plume containing about 100 pounds  12 1/2 gallons  of water.

"It'll be about a bathtub full,'' he said.

Binder said chances of success are not strong, but the payoff would be big for science and exploration if lunar water is proven.

Water on the moon could be chemically broken down into oxygen and hydrogen to make fuel for rockets or for electrical generators. The oxygen also could supply an atmosphere for a lunar base.

"My goal is to one day set up a lunar base,'' said Binder. Water there, he said, would "make it a lot cheaper.''

Goldstein's idea was that, if frozen water is in the crater, then the collision would vaporize the ice and create a vapor of water molecules.

Sunlight would quickly break down the water into hydrogen and hydroxyl, a chemical formed when ultraviolet radiation frees a hydrogen atom from water.

If the vapor cloud is dense enough, Goldstein said, sunlight will cause the hydroxyl molecules to be visible to powerful telescopes using ultraviolet radiation detectors.

Binder sees little likelihood that amateur astronomers will be able to detect the impact cloud over the lunar south pole, but he added: "I would encourage anyone to try.''

The crash site will become the final resting place for Eugene Shoemaker. The famed U.S. Geological Survey astronomer was one of the world's leading authorities on lunar impacts. After he died two years ago, a small metal container filled with his ashes was glued to one of Prospector's braces before the craft was launched.

Binder said the lipstick-sized container will be scattered across the lunar crater, along with the rest of the little craft.

-- Roland (nottelling@nowhere.com), July 30, 1999

Answers

I frankly am sick to death of human being constantly meddling with things that are doing fine without any interference from scientists wanting to experiment. So much degradation has been done to this planet by our modern way of life, that we have managed to create a nice little bake oven in which to toast ourselves. It's l06 degrees right now on our thermometer which is hanging in the shade.

-- gilda (jess@listbot.com), July 30, 1999.

"Anyone who lives within 50 miles of planet Earth is toast"...

Trademark pending.

R.

-- Roland (nottelling@nowhere.com), July 30, 1999.

I hope that those who are dismayed by the plan to guide the Lunar Prospector to a crash that may provide valuable evidence about the presence of waterr on the Moon realize that the sacecraft is going to crash somewhere on the Moon anyway. All this plan does is change the crash point from an undetermined location to a planned location.

There was never enough fuel on the spacecraft to enable sending it out of lunar orbit once it was there, and the Moon's "lumpy" gravitational field guarantees that anything orbiting it will crash sooner or later unless a force is applied to send that thing out of the Moon's gravitational influence.

-- No Spam Please (nos_pam_please@hotmail.com), July 31, 1999.

Great laugh, Roland. Thank you.

I know what you're saying, Gilda. I feel that way myself sometimes. But, y'know, that's what we do. It's what we've always done. And we're not the only animals that have "insatiable curteosity" ---just the ones with the biggest brains and most dexterous digits.

Even in the Rift Valley days at Lake Turkana, we always looked for a better, easier, safer way. And, when we had time, just took things apart to see how they worked---just like any eight-year-old---and we still do. The only difference is the clout we've accumulated over the centimillenia.

But, not to worry, even if this glitch thingie is just a bump, you and I know there's a brick wall up ahead---"The next stop..." [in best Rod Serling voice]

Hallyx

"..then seemingly on the threshold of some supreme accomplishment which was to have crowned their entire history, this all-but-divine race perished in a single night!" - Dr. Morbius (Forbidden Planet?)

-- (Hallyx@aol.com), July 31, 1999.