First of NASA's GRAIL spacecraft enters Moon orbit

First of NASA's GRAIL spacecraft enters Moon orbit
Artist concept of GRAIL mission. Image credit: NASA/JPL-Caltech

( -- The first of two NASA spacecraft to study the moon in unprecedented detail has entered lunar orbit.

NASA's Gravity Recovery And Interior Laboratory (GRAIL)-A spacecraft successfully completed its planned main engine burn at 2 p.m. PST (5 p.m. EST) today. As of 3 p.m. PST (6 p.m. EST), GRAIL-A is in an of 56 miles by 5,197 miles (90 kilometers by 8,363 kilometers) around the moon that takes approximately 11.5 hours to complete.

"My resolution for the new year is to unlock lunar mysteries and understand how the moon, Earth and other evolved," said Maria Zuber, GRAIL principal investigator at the Massachusetts Institute of Technology in Cambridge. "Now, with GRAIL-A successfully placed in orbit around the moon, we are one step closer to achieving that goal."

The next mission milestone occurs tomorrow when GRAIL-A's mirror twin, GRAIL-B, performs its own main engine burn to place it in lunar orbit. At 3 p.m. PST (6 p.m. EST) today, GRAIL-B was 30,018 miles (48,309 kilometers) from the moon and closing at a rate of 896 mph (1,442 kilometers per hour). GRAIL-B's insertion burn is scheduled to begin tomorrow, Jan. 1, at 2:05 p.m. PST (5:05 p.m. EST) and will last about 39 minutes.

"With GRAIL-A in we are halfway home," said David Lehman, GRAIL project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Tomorrow may be New Year's everywhere else, but it's another work day around the moon and here at JPL for the GRAIL team."

Once both spacecraft are confirmed in orbit and operating, science work will begin in March. The spacecraft will transmit precisely defining the distance between them as they orbit the moon in formation. As they fly over areas of greater and lesser gravity caused by both visible features, such as mountains and craters, and masses hidden beneath the , the distance between the two spacecraft will change slightly.

Scientists will translate this information into a high-resolution map of the moon's gravitational field. The data will allow scientists to understand what goes on below the lunar surface. This information will increase knowledge of how Earth and its rocky neighbors in the inner solar system developed into the diverse worlds we see today.

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Jan 01, 2012
What kind of resolution will this mission have in defining the extent of underground caverns and lava tubes? How small of a cavity will they be able to define? And how deep?

Jan 01, 2012
Mayday: The MoonKAM cameras (4 per satellite) will be controlled by middle school students. I can't find any discussion of their resolution but I suspect it is not top of the line. The primary purpose of the mission is to detect changes in distances between the satellites due to the Moon's gravity changes, thereby mapping the interior density on the moon. The differences that can be detected are said to be as small as a red blood cell.

Jan 01, 2012
What a jackass! The constitution is a "living" document, written in such a way as "we the people" could continue to update it to meet our needs and address current circumstances.
But back to the GRAIL satellites - NASA has done an outstanding job creating them, with an incredibly limited budget, hamstrung by congressional interference and unnecessary bureaucracy, and state of the art science. Kudos to NASA!

Jan 01, 2012
Ok, V.D., you've demonstrated that you understand the concept of quotation marks. Now how about refuting Rand Paul's ARGUMENT?

Or are you just going to call me a tard and move on?

Jan 01, 2012
Yah, thought so. Tard.

Jan 02, 2012
Somebody should put you guys in the ring with some sock'em boppers.

I'd pay good money to see that :P

I wonder how far down below the surface they'll be able to map ? ...all the way to the secret treasure chamber of the great Zardoz ?...he was here in 1135 ya' know.


All-purpose campaign song:


Jan 02, 2012
Refutation: No one has a right to enter another's house without due process of the law. Rand chose to be a pohysician, with all the late hours and hard work that implies, and also with very high annual earnings ($200,000 and up). Some slave! Heath care guaranteed by the government (but provided by private physicians) hardly makes him a slave, as he can refuse to take the patient, and thereby refuse the government's payments. But WAIT! He is no longer a physician - he is a Senator, making far more money from corporate buyouts than ever dreamed by being a physician. No, we are not enslaving anyone with universal healthcare. They still make great money, and no one gets to whip them, starve them, mistreat them, sell them or their offspring as one might do to a slave.

Jan 04, 2012
>> I'd pay good money to be in the ring.

Tough talk, Scott. Aren't you just a little concerned that one of us hairy-knuckled types might show up on your doorstep one day to take you at your word?

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