FILE - These two satellite images provided by NASA taken on July 28, 2010, left, and Aug. 5, 2010, right, shows the Petermann Glacier in Northern Greenland. A giant ice island, seen in image at right, has broken off the Petermann Glacier. A University of Delaware researcher says the floating ice sheet covers 100 square miles (260 sq. kilometers) _ more than four times the size of New York's Manhattan Island. The World Meteorological Organization (WMO) says the weather-related cataclysms of July and August fit patterns predicted by climate scientists, although those scientists always shy from tying individual disasters directly to global warming. (AP Photo/NASA)
This image provided by the Alaska State Troopers shows the wreckage of the amphibious plane carrying former Sen. Ted Stevens and former NASA chief Sean O'Keefe that crashed into a remote Alaska mountainside during a fishing trip, killing Mr. Stevens and four others and stranding the survivors on a rocky, brush-covered slope overnight. The plane hit the ground with so much force that it left a 300-foot gash on the slope, federal investigators said. (AP Photo/Alaska State Troopers)
This Aug. 5, 2010 satellite image provided by NASA shows an ice island that has broken off the Petermann Glacier in northern Greenland. A University of Delaware researcher says the floating ice sheet covers 100 square miles (260 sq. kilometers) _ more than four times the size of New York's Manhattan Island. (AP Photo/NASA)
** FILE ** Former NASA Administrator Sean O'Keefe (The Washington Times)
In this photo taken from NASA television, Expedition 24 astronauts work outside the space station, Monday, Aug. 16, 2010. (AP Photo/NASA)
In this x-ray photo provided by NASA, the sun is shown early in the morning of Sunday, Aug. 1, 2010. The dark arc near the top right edge of the image is a filament of plasma blasting off the surface _ part of the coronal mass ejection. The bright region is an unassociated solar flare. When particles from the eruption reach Earth on the evening of Aug. 3-4, they may trigger a brilliant auroral display known as the Northern Lights. (AP Photo/NASA)
NASA's muscular R2 astronaut "helper" robot has announced by Twitter that it has no gender. (NASA photo)
FILE - This Feb. 19. 2010 file photo provided by NASA shows the International Space Station with Earth's horizon as a backdrop. Several power systems have been shut down aboard the International Space Station after a cooling system malfunctioned. NASA says in a posting on its website that one of two cooling loops aboard the space station was shut down Saturday, July 31, 2010. A module that pumps ammonia coolant to prevent equipment from overheating was still shut down early Sunday, Aug. 1. (AP Photo/NASA, File)
Illustration: NASA crescent
**FILE** In this April 21, 2008, file photo, Professor Stephen Hawking of the University of Cambridge makes remarks at an event marking the 50th anniversary of NASA, at George Washington University in Washington. (Associated Press)
NASA Administrator Charles Bolden testified on Capitol Hill in February 2010.
** FILE ** Rep. Gabrielle Giffords, Arizona Democrat, talks with NASA chief Charles Bolden before his testimony on NASA's fiscal 2011 budget in February. (AP Photo)
This artist rendering shows NASA's next generation of moon rockets being developed at the Marshall Space Flight Center in Huntsville, Ala. Preliminary work on two Ares spacecraft has already cost NASA $7 billion.
** FILE ** Gary McKinnon, shown in this file photo from 2009, is charged with breaking into computers belonging to NASA, the Department of Defense and several branches of the U.S. military. (Associated Press)
An artist depicts NASA's Phoenix Mars Lander, which touched down on the Red Planet on May 26. The landing was one of NASA's favorite advances of the year. (NASA/Jet Propulsion Laboratory)