Greetings fellow astrophiles,
The NASA News service provides up-to-date announcements of NASA policy, news events, and space science. A recent selection of space science articles are provided below, including direct links to the full announcements. Those interested in receiving these news announcements directly from NASA can subscribe to their service by sending an email to:
hqnews-request@newsletters.nasa.gov?subject=subscribe
NASA’s Mars Spacecraft Maneuvers to Prepare for Close Comet Flyby
RELEASE 14-201 (Click here for the full article) – 25 July 2014
NASA is taking steps to protect its Mars orbiters, while preserving opportunities to gather valuable scientific data, as Comet C/2013 A1 Siding Spring heads toward a close flyby of Mars on Oct. 19.
The comet’s nucleus will miss Mars by about 82,000 miles (132,000 kilometers), shedding material hurtling at about 35 miles (56 kilometers) per second, relative to Mars and Mars-orbiting spacecraft. At that velocity, even the smallest particle — estimated to be about one-fiftieth of an inch (half a millimeter) across — could cause significant damage to a spacecraft.
NASA currently operates two Mars orbiters, with a third on its way and expected to arrive in Martian orbit just a month before the comet flyby. Teams operating the orbiters plan to have all spacecraft positioned on the opposite side of the Red Planet when the comet is most likely to pass by.
…
For more information about the Mars flyby of comet Siding Spring, visit: mars.nasa.gov/comets/sidingspring/For more information about NASA’s Mars Exploration Program, visit: www.nasa.gov/mars
NASA’s Long-Lived Mars Opportunity Rover Sets Off-World Driving Record
RELEASE 14-202 (Click here for the full article) – 28 July 2014
NASA’s Opportunity Mars rover, which landed on the Red Planet in 2004, now holds the off-Earth roving distance record after accruing 25 miles (40 kilometers) of driving. The previous record was held by the Soviet Union’s Lunokhod 2 rover.
“Opportunity has driven farther than any other wheeled vehicle on another world,” said Mars Exploration Rover Project Manager John Callas, of NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California. “This is so remarkable considering Opportunity was intended to drive about one kilometer and was never designed for distance. But what is really important is not how many miles the rover has racked up, but how much exploration and discovery we have accomplished over that distance.”
…
For more information about NASA’s Mars rovers Spirit and Opportunity, visit: www.nasa.gov/rovers and marsrovers.jpl.nasa.govFollow the project on Twitter at: twitter.com/MarsRovers
On Facebook, visit: www.facebook.com/mars.rovers
An image of Lunokhod 2’s tracks, as imaged by NASA’s LRO, is available online at:
lroc.sese.asu.edu/posts/774
NASA’s Hubble Finds Supernova Star System Linked to Potential “Zombie Star”
RELEASE 14-212 (Click here for the full article) – 6 August 2014
Using NASA’s Hubble Space Telescope, a team of astronomers has spotted a star system that could have left behind a “zombie star” after an unusually weak supernova explosion.
A supernova typically obliterates the exploding white dwarf, or dying star. On this occasion, scientists believe this faint supernova may have left behind a surviving portion of the dwarf star — a sort of zombie star.
While examining Hubble images taken years before the stellar explosion, astronomers identified a blue companion star feeding energy to a white dwarf, a process that ignited a nuclear reaction and released this weak supernova blast. This supernova, Type Iax, is less common than its brighter cousin, Type Ia. Astronomers have identified more than 30 of these mini-supernovas that may leave behind a surviving white dwarf.
…
For images and more information about Hubble, visit:
www.nasa.gov/hubble and hubblesite.org/news/2014/32
NASA’s NuSTAR Sees Rare Blurring of Black Hole Light
RELEASE 14-210 (Click here for the full article) – 12 August 2014
NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) has captured an extreme and rare event in the regions immediately surrounding a supermassive black hole. A compact source of X-rays that sits near the black hole, called the corona, has moved closer to the black hole over a period of just days.
“The corona recently collapsed in toward the black hole, with the result that the black hole’s intense gravity pulled all the light down onto its surrounding disk, where material is spiraling inward,” said Michael Parker of the Institute of Astronomy in Cambridge, United Kingdom, lead author of a new paper on the findings appearing in the Monthly Notices of the Royal Astronomical Society.
…
For more information on NuSTAR, visit: www.nasa.gov/nustar
NASA’s Chandra Observatory Searches for Trigger of Nearby Supernova
RELEASE 14-216 (Click here for the full article) – 14 August 2014
New data from NASA’s Chandra X-ray Observatory offer a glimpse into the environment of a star before it exploded earlier this year, and insight into what triggered one of the closest supernovas witnessed in decades.
The data gathered on the Jan. 21 explosion, a Type Ia supernova, allowed scientists to rule out one possible cause. These supernovas may be triggered when a white dwarf takes on too much mass from its companion star, immersing it in a cloud of gas that produces a significant source of X-rays after the explosion.
Astronomers used NASA’s Swift and Chandra telescopes to search the nearby Messier 82 galaxy, the location of the explosion, for such an X-ray source. However, no source was found, revealing the region around the site of the supernova is relatively devoid of material.
…
For an additional interactive image, podcast, and video on the findings, visit: chandra.si.eduFor a preprint of the study results in The Astrophysical Journal, visit: arxiv.org/abs/1405.1488
For Chandra images, multimedia and related materials, visit: www.nasa.gov/chandra
