Wednesday 13 February 2013

Supernova explosion


The highly distorted supernova remnant shown in this image may contain the most recent black hole formed in the Milky Way galaxy. The image combines X-rays from NASA's Chandra X-ray Observatory in blue and green, radio data from the NSF's Very Large Array in pink, and infrared data from Caltech's Palomar Observatory in yellow.

The remnant, called W49B, is about a thousand years old, as seen from Earth, and is at a distance about 26,000 light years away.

The supernova explosions that destroy massive stars are generally symmetrical, with the stellar material blasting away more or less evenly in all directions. However, in the W49B supernova, material near the poles of the doomed rotating star was ejected at a much higher speed than material emanating from its equator. Jets shooting away from the star's poles mainly shaped the supernova explosion and its aftermath.

This may be the youngest black hole formed in the Milky Way galaxy, with an age of only about a thousand years, as viewed from Earth.  The new results on W49B, which were based on about two-and-a-half days of Chandra observing time, appear in a paper in the Feb. 10, 2013 issue of the Astrophysical Journal. The authors of the paper are Laura Lopez, from the Massachusetts Institute of Technology (MIT), Enrico Ramirez-Ruiz from the University of California at Santa Cruz, Daniel Castro, also of MIT, and Sarah Pearson from the University of Copenhagen in Denmark.

Credits: X-ray: NASA/CXC/MIT/L.Lopez et al; Infrared: Palomar; Radio: NSF/NRAO/VLA

Saturday 9 February 2013

NASA Curiosity Rover Collects First Martian Bedrock Sample


Image credit: NASA/JPL-Caltech/MSSS
NASA's Curiosity rover has, for the first time, used a drill carried at the end of its robotic arm to bore into a flat, veined rock on Mars and collect a sample from its interior. This is the first time any robot has drilled into a rock to collect a sample on Mars. 

The fresh hole, was drilled 2.5 inches (6.4 centimeters) deep in a patch of fine-grained sedimentary bedrock,  believed to hold evidence about long-gone wet environments. In pursuit of that evidence, the rover will use its laboratory instruments to analyze rock powder collected by the drill.

John Grunsfeld, NASA associate administrator for the agency's Science Mission Directorate, said "This is the biggest milestone accomplishment for the Curiosity team since the sky-crane landing last August, another proud day for America."

For the next several days, ground controllers will command the rover's arm to carry out a series of steps to process the sample, ultimately delivering portions to the instruments inside.

Before the rock powder is analyzed, some will be used to scour traces of material that may have been deposited onto the hardware while the rover still was on Earth, despite thorough cleaning before launch.

Inside the sample-handling device, the powder will be vibrated once or twice over a sieve that screens out any particles larger than six-thousandths of an inch (150 microns) across. Small portions of the sieved sample will fall through ports on the rover deck into the Chemistry and Mineralogy (CheMin) instrument and the Sample Analysis at Mars (SAM) instrument. These instruments then will begin the much-anticipated detailed analysis.

For more about the mission, visit:  http://www.nasa.gov/msl