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:
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NASA’s Chandra X-Ray Observatory Celebrates 15th Anniversary
RELEASE 14-196 (Click here for the full article) – 22 July 2014
Fifteen years ago, NASA’s Chandra X-ray Observatory was launched into space aboard the Space Shuttle Columbia. Since its deployment on July 23, 1999, Chandra has helped revolutionize our understanding of the universe through its unrivaled X-ray vision.
Chandra, one of NASA’s current “Great Observatories,” along with the Hubble Space Telescope and Spitzer Space Telescope, is specially designed to detect X-ray emission from hot and energetic regions of the universe.
With its superb sensitivity and resolution, Chandra has observed objects ranging from the closest planets and comets to the most distant known quasars. It has imaged the remains of exploded stars, or supernova remnants, observed the region around the supermassive black hole at the center of the Milky Way, and discovered black holes across the universe. Chandra also has made a major advance in the study of dark matter by tracing the separation of dark matter from normal matter in collisions between galaxy clusters. It also is contributing to research on the nature of dark energy.
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Additional details, images and an animation are available at: www.ciclops.org/view_event/202
More information about Cassini is available at: www.nasa.gov/cassini and saturn.jpl.nasa.gov
Hubble Finds Three Surprisingly Dry Exoplanets
RELEASE 14-197 (Click here for the full article) – 24 July 2014
Astronomers using NASA’s Hubble Space Telescope have gone looking for water vapor in the atmospheres of three planets orbiting stars similar to the sun — and have come up nearly dry.
The three planets, known as HD 189733b, HD 209458b, and WASP-12b, are between 60 and 900 light-years away from Earth and were thought to be ideal candidates for detecting water vapor in their atmospheres because of their high temperatures where water turns into a measurable vapor.
These so-called “hot Jupiters” are so close to their star they have temperatures between 1,500 and 4,000 degrees Fahrenheit, however, the planets were found to have only one-tenth to one one-thousandth the amount of water predicted by standard planet-formation theories.
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For images and more information about Hubble, visit: www.nasa.gov/hubble and hubblesite.org/news/2014/36
Cassini Spacecraft Reveals 101 Geysers and more on Icy Saturn Moon
RELEASE 14-203 (Click here for the full article) – 28 July 2014
Scientists using mission data from NASA’s Cassini spacecraft have identified 101 distinct geysers erupting on Saturn’s icy moon Enceladus. Their analysis suggests it is possible for liquid water to reach from the moon’s underground sea all the way to its surface.
These findings, and clues to what powers the geyser eruptions, are presented in two articles published in the current online edition of the Astronomical Journal.
Over a period of almost seven years, Cassini’s cameras surveyed the south polar terrain of the small moon, a unique geological basin renowned for its four prominent “tiger stripe” fractures and the geysers of tiny icy particles and water vapor first sighted there nearly 10 years ago. The result of the survey is a map of 101 geysers, each erupting from one of the tiger stripe fractures, and the discovery that individual geysers are coincident with small hot spots. These relationships pointed the way to the geysers’ origin.
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Additional details, images and an animation are available at: www.ciclops.org/view_event/202
More information about Cassini is available at: www.nasa.gov/cassini and saturn.jpl.nasa.gov
Hubble Shows Farthest Lensing Galaxy Yields Clues to Early Universe
RELEASE 14-205 (Click here for the full article) – 31 July 2014
Astronomers using NASA’s Hubble Space Telescope have unexpectedly discovered the most distant galaxy that acts as a cosmic magnifying glass. Seen here as it looked 9.6 billion years ago, this monster elliptical galaxy breaks the previous record-holder by 200 million years.
These “lensing” galaxies are so massive that their gravity bends, magnifies, and distorts light from objects behind it, a phenomenon called gravitational lensing. Finding one in such a small area of the sky is so rare that you would normally have to survey a region hundreds of times larger to find just one.
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For images and more information about Hubble, visit: www.nasa.gov/hubble and hubblesite.org/news/2014/33
NASA’s Fermi Space Telescope Reveals New Source of Gamma Rays
RELEASE 14-209 (Click here for the full article) – 31 July 2014
Observations by NASA’s Fermi Gamma-ray Space Telescope of several stellar eruptions, called novae, firmly establish these relatively common outbursts almost always produce gamma rays, the most energetic form of light.
“There’s a saying that one is a fluke, two is a coincidence, and three is a class, and we’re now at four novae and counting with Fermi,” said Teddy Cheung, an astrophysicist at the Naval Research Laboratory in Washington, and the lead author of a paper reporting the findings in the Aug. 1 edition of the journal Science.
A nova is a sudden, short-lived brightening of an otherwise inconspicuous star caused by a thermonuclear explosion on the surface of a white dwarf, a compact star not much larger than Earth. Each nova explosion releases up to 100,000 times the annual energy output of our sun. Prior to Fermi, no one suspected these outbursts were capable of producing high-energy gamma rays, emission with energy levels millions of times greater than visible light and usually associated with far more powerful cosmic blasts.
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For more information about Fermi, visit: www.nasa.gov/fermi
Greetings fellow astrophiles!
