Brisbane Times NASA: Closest planet to sun, Mercury, harbors ice

This photo made available by NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington on Tuesday, Nov. 27, 2012 shows a 68-mile-diameter crater, large indentation at center, in the north polar region of Mercury which has been shown to harbor water ice, thanks to measurements by the Messenger spacecraft. Scientists made the announcement Thursday, Nov. 29, 2012. (AP Photo/NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)  

CAPE CANAVERAL, Fla. (AP) — Just in time for Christmas, scientists have confirmed a vast amount of ice at the north pole — on Mercury, the closest planet to the sun.

The findings are from NASA’s Mercury-orbiting probe, Messenger, and the subject of three scientific papers released Thursday by the journal Science.

The frozen water is located in regions of Mercury’s north pole that always are in shadows, essentially impact craters. It’s believed the south pole harbors ice as well, though there are no hard data to support it. Messenger orbits much closer to the north pole than the south.

‘‘If you add it all up, you have on the order of 100 billion to 1 trillion metric tons of ice,’’ said David Lawrence of the Applied Physics Laboratory at Johns Hopkins University. ‘‘The uncertainty on that number is just how deep it goes.’’

The ice is thought to be at least 1½ feet deep — and possibly as much as 65 feet deep.

There’s enough polar ice at Mercury, in fact, to bury an area the size of Washington, D.C., by two to 2½ miles deep, said Lawrence, the lead author of one of the papers.

‘‘These are very exciting results,’’ he added at a news conference.

For two decades, radar measurements taken from Earth have suggested the presence of ice at Mercury’s poles. Now scientists know for sure, thanks to Messenger, the first spacecraft to orbit Mercury.

The water almost certainly came from impacting comets, or possibly asteroids. Ice is found at the surface, as well as buried under a dark material.

Messenger was launched in 2004 and went into orbit 1½ years ago around Mercury, where temperatures reach 800 degrees. NASA hopes to continue observations well into next year.

Columbia University’s Sean Solomon, principal scientist for Messenger, stressed that no one is suggesting that Mercury might hold evidence of life, given the presence of water. But the latest findings may help explain how water and other building blocks of life arrived elsewhere in the solar system, he said.

Mercury is becoming the subject of new interest ‘‘where it wasn’t much of one before,’’ Solomon said.

U.S. government confirms world won't end in 2012

 

The U.S. government is rebutting claims that the end is nigh.
"The world will not end on December 21, 2012, or any day in 2012," an unsigned USA.gov blog asserts.
Some New Age theorists believe that the ancient Mayan civilization predicted a late December doomsday for all of humanity. Others believe the date signifies the start of a new era. Their predictions are based on the idea that the Mayan Long Count calendar "ends" in 2012 — something that scholars say is a misrepresentation.
"False rumors about the end of the world in 2012 have been commonplace on the Internet for some time. Many of these rumors involve the Mayan calendar ending in 2012 (it won’t), a comet causing catastrophic effects (definitely not), a hidden planet sneaking up and colliding with us (no and no), and many others," the government asserts in the post.
"Unfortunately, these rumors have many people frightened, especially children," the blog post says, noting that NASA has gotten more than 1,000 letters from Americans concerned about the apocalypse.
"At least a once a week I get a message from a young person — as young as 11 — who says they are ill and/or contemplating suicide because of the coming doomsday," David Morrison, a planetary astronomer and senior scientist for NASA who answers questions from the public about astrobiology tells USA.gov.
The government's blog post, however, seems to leave open the possibility of doomsday occurring in 2013 or beyond.