The Herschel spacecraft, launched by the European Space Agency, has determined that water in the upper atmosphere of Saturn comes from the moon Enceladus, which orbits approximately 238,000 km from the planet. Enceladus spews water into space at a rate of 250kg/s. Scientists estimate that between 3-5% of that is captured by Saturn, which is enough to account for the levels of water found in Saturn’s atmosphere.
Astronomers have discovered the first asteroid to orbit in the leading Lagrange point of the Earth. 2010 TK7 is nearly 300m across and has an irregular orbit which can bring it within 20 million kilometers of the Earth. The asteroid was discovered by the Near Earth Orbit project using the WISE satellite, launched in 2009.
Images from the Lunar Reconnaissance Orbiter may show the crash site of the Lunar Orbiter 2, which helped map potential landing sites for Apollo missions in 1967. After completing its mission, NASA instructed the LO2 to crash into the farside of the moon, although the exact location of its crash was unknown. The LRO was launched in 2009 to fully map the lunar surface and create 3D maps for a potential return to the moon. The LRO has previously mapped all six Apollo landing sites and has found evidence of volcanism on the moon.
The space shuttle Atlantis landed this morning at 5:57:00, completing both STS-135 and the shuttle program. The first shuttle, Columbia was launched in April 1981. Over the intervening thirty years, two shuttles and their crews were lost in flight, five shuttles flew in total, and the crafts traveled a total of 548,049,445 miles. The landing of Atlantis marks the first time in 30 years that the United States has not had the capacity to put humans into space. Atlantis will spend its retirement on display at the Kennedy Space Center.
Scientists have announced the discovery of a fourth moon in orbit around Pluto. Pluto’s first discovered moon, Charon, was found in 1978. Two more moons, Nyx and Hydra, were identified in 2005. The new moon, which is currently called P4, is believed to be between 13 and 34 km in diameter and orbits Pluto every 32 days at a distance of about 59,000 km, between the orbits of Nyx and Hydra.
NASA’s Dawn Spacecraft entered orbit around the asteroid Vesta at 1 am on July 16. This is the first time an asteroid has been orbited by a spacecraft. Dawn will orbit Vesta, which was the fourth asteroid discovered, until July 2012 when the spacecraft will travel to the dwarf planet Ceres, which was the first asteroid discovered.
NASA launched the Space Shuttle Atlantis on STS-135, its final mission, and the final mission of the 30 year long shuttle program at 11:29 ET. The mission was delayed with an unexpected hold at T-31 seconds when an error indicated that the Gaseous Oxygen Vent Arm had not fully retracted. Visual examination showed the error was a computer glitch and the countdown continued. Originally, Atlantis was supposed to have flown its last mission in May, 2010, but the current mission was added on October 11, 2010. The first shuttle launch, of Columbia, occurred on April 12, 1981.
Asteroid 2011 MD is expected to pass less than 8,000 miles above Earth’s surface on Monday, June 27. Closest approach will take place off the coast of Antarctica, but the asteroid may be visible from the Americas, the Pacific, and eastern Asia prior to its passage.
A 7 meter long asteroid, 2009 BD, passed within 346,000 kilometers of the Earth on June 2, coming inside the Moon’s orbit. Because 2009 BD is a co-orbital object, it will remain relatively close to the Earth for the next month or so, generally about 3,850,000 km away.
NASA sent the shutdown command to the Mars Spirit Rover on May 25, seven years after the exploration vehicle landed. Spirit was scheduled to operate for approximately three weeks and cover a distance of a couple hundred yards. Instead, it operated for more than five years and covered almost five miles. Spirit made its last transmission on March 22, 2010. Spirit‘s sister craft, Opportunity, is still operating.