Friday, October 18, 2013

MAVEN Prelaunch Updates



MAVEN Launch Preps on Schedule
Fri, 18 Nov 2013 10:40 AM EDT
MAVEN launch preparations remain on schedule and have continued to go well since spacecraft processing resumed earlier this month. On Tuesday, Oct. 22, MAVEN is slated for a spin test without propellant aboard. Once complete, the spacecraft will be prepared for fueling. The Atlas V rocket payload fairing will be moved into the clean room on Oct. 21 in preparation for MAVEN's encapsulation beginning in early November.
The Atlas booster was hoisted into the vertical integration facility at Cape Canaveral Air Force Station's Space Launch Complex 41 on Oct. 11, and the Centaur upper stage was hoisted atop the Atlas the following Monday. United Launch Alliance has completed powering of the stacked vehicle for checkout. The Combined Systems Test, an electrical test of the rocket, is scheduled for Oct. 22.
The launch of MAVEN is scheduled for Nov. 18 at 1:28 p.m. EST.

Source: http://www.nasa.gov/

Asteroid 2013 TV135 – A Reality Check



Newly discovered asteroid 2013 TV135 made a close approach to Earth on Sept. 16, when it came within about 4.2 million miles (6.7 million kilometers). The asteroid is initially estimated to be about 1,300 feet (400 meters) in size and its orbit carries it as far out as about three quarters of the distance to Jupiter's orbit and as close to the sun as Earth's orbit. It was discovered on Oct. 8, 2013, by astronomers working at the Crimean Astrophysical Observatory in Ukraine. As of Oct. 14, asteroid 2013 TV135 is one of 10,332 near-Earth objects that have been discovered.
With only a week of observations for an orbital period that spans almost four years, its future orbital path is still quite uncertain, but this asteroid could be back in Earth’s neighborhood in 2032. However, NASA’s Near-Earth Object Program Office states the probability this asteroid could then impact Earth is only one in 63,000. The object should be easily observable in the coming months and once additional observations are provided to the Minor Planet Center in Cambridge, Mass., the initial orbit calculations will be improved and the most likely result will be a dramatic reduction, or complete elimination, of any risk of Earth impact.  
"To put it another way, that puts the current probability of no impact in 2032 at about 99.998 percent," said Don Yeomans, manager of NASA's Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, Calif. "This is a relatively new discovery. With more observations, I fully expect we will be able to significantly reduce, or rule out entirely, any impact probability for the foreseeable future."
NASA detects, tracks and characterizes asteroids and comets passing close to Earth using both ground- and space-based telescopes. The Near-Earth Object Observations Program, commonly called "Spaceguard," discovers these objects, characterizes a subset of them and identifies their orbits to determine if any could be potentially hazardous to our planet.
JPL manages the Near-Earth Object Program Office for NASA's Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology in Pasadena.
More information about asteroids and near-Earth objects is at: http://www.jpl.nasa.gov/asteroidwatch

Friday, October 11, 2013

Legless geckos slither using skin ridges



A belly carpeted in flattened ridges may help legless lizards slither. Some geckos have only two tiny tabs for legs, so they wriggle and glide like snakes.
These geckos may propel themselves with microscopic corduroy-like ribs on their skin, Marlene Spinner of the University of Kiel in Germany and colleagues suggest October 9 in the Proceedings of the Royal Society B. Unlike geckos with legs, which owe their sticky grip to spines on the skin, the flap-footed lizard Lialis jicari is spine-free where skin skims the ground.
Instead, the reptile carries blunt nubs on the chin and rows of orderly ripples on the stomach, the team discovered by examining freshly shed skin under a microscope. The skin ribs could reduce friction as the animals slide forward.

Source: www.sciencenews.org

Voyager's view


It’s finally official: Voyager 1 has become the first human-made object to enter interstellar space, mission scientists report September 12 in Science. On August 25, 2012, the scientists say, Voyager 1 exited a giant invisible bubble called the heliosphere that is inflated by a torrent of subatomic particles spewing from the sun. Now the probe is surrounded almost exclusively by particles produced by other stars. But whether it’s correct to say that the probe has left the solar system depends on how you define the solar system. “From my perspective, Voyager is nowhere near the edge of the solar system,” says planetary scientist Hal Levison of the Southwest Research Institute in Boulder, Colo. The sun continues to exert gravitational dominance out to hundreds of times the distance of Voyager 1 from the sun, where trillions of icy pebbles, boulders and comets orbit. In the last 36 years, Voyager has traveled an impressive 25.4 billion kilometers, but it still has a long way to go to unambiguously depart the solar system.

Source: www.sciencenews.org