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Archive for December 20, 2011

First Earth-Sized Planets Found

December 20, 2011 Leave a comment

Credit: NASA/JPL-Caltech/T. Pyle

Credit: NASA/JPL-Caltech/T. Pyle

Astronomers using NASA’s Kepler mission have detected two Earth-sized planets orbiting a distant star. This discovery marks a milestone in the hunt for alien worlds, since it brings scientists one step closer to their ultimate goal of finding a twin Earth.

“The goal of Kepler is to find Earth-sized planets in the habitable zone. Proving the existence of Earth-sized exoplanets is a major step toward achieving that goal,” said Francois Fressin of the Harvard-Smithsonian Center for Astrophysics (CfA).

The paper describing the finding will be published in the journal Nature.

The two planets, dubbed Kepler-20e and 20f, are the smallest planets found to date. They have diameters of 6,900 miles and 8,200 miles – equivalent to 0.87 times Earth (slightly smaller than Venus) and 1.03 times Earth. These worlds are expected to have rocky compositions, so their masses should be less than 1.7 and 3 times Earth’s.

Full Story: http://www.cfa.harvard.edu/news/2011/pr201134.html

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Celestial Bauble Intrigues Astronomers

December 20, 2011 Leave a comment

Credit: X-ray & Optical: NASA/CXC/Univ.Potsdam/L.Oskinova et al

Credit: X-ray & Optical: NASA/CXC/Univ.Potsdam/L.Oskinova et al

With the holiday season in full swing, a new image from an assembly of telescopes has revealed an unusual cosmic ornament. Data from NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton have been combined to discover a young pulsar in the remains of a supernova located in the Small Magellanic Cloud, or SMC. This would be the first definite time a pulsar, a spinning, ultra-dense star, has been found in a supernova remnant in the SMC, a small satellite galaxy to the Milky Way.

In this composite image, X-rays from Chandra and XMM-Newton have been colored blue and optical data from the Cerro Tololo Inter-American Observatory in Chile are colored red and green. The pulsar, known as SXP 1062, is the bright white source located on the right-hand side of the image in the middle of the diffuse blue emission inside a red shell. The diffuse X-rays and optical shell are both evidence for a supernova remnant surrounding the pulsar. The optical data also displays spectacular formations of gas and dust in a star-forming region on the left side of the image. A comparison of the Chandra image with optical images shows that the pulsar has a hot, massive companion.

Full Story: http://www.chandra.harvard.edu/photo/2011/sxp1062/

Comet Lovejoy Visible at Sunrise

December 20, 2011 Leave a comment

Noted astronomer John Bortle urges observers (especially in the southern hemisphere) to “begin searching for Comet Lovejoy’s bright tail projecting up out of the morning twilight beginning at dawn. The tails of some of the major sungrazing comets have been extraordinarily bright. Comet Lovejoy’s apparition has been so bizarre up to this point that it is difficult to anticipate just what might happen next … [including] the exact sort of tail it might unfurl in the morning sky.”

Full Story: http://spaceweather.com/archive.php?view=1&day=20&month=12&year=2011

Evidence for Complex Molecules on Pluto’s Surface

December 20, 2011 Leave a comment

The new and highly sensitive Cosmic Origins Spectrograph aboard the Hubble Space Telescope has discovered a strong ultraviolet-wavelength absorber on Pluto’s surface, providing new evidence that points to the possibility of complex hydrocarbon and/or nitrile molecules lying on the surface, according to a paper recently published in the Astronomical Journal by researchers from Southwest Research Institute and Nebraska Wesleyan University.

Such chemical species can be produced by the interaction of sunlight or cosmic rays with Pluto’s known surface ices, including methane, carbon monoxide and nitrogen.

The project, led by SwRI’s Dr. Alan Stern, also included SwRI researchers Dr. John Spencer and Adam Shinn, and Nebraska Wesleyan University researchers Dr. Nathaniel Cunningham and student Mitch Hain.

Full Story: http://www.swri.org/9what/releases/2011/pluto.htm

NASA’s Kepler Announcing Newly Confirmed Planets

December 20, 2011 Leave a comment

NASA will host a news teleconference at 1 p.m. EST, Tuesday, Dec. 20, announcing new discoveries by the Kepler mission.

Kepler is the first NASA mission capable of finding Earth-size planets in or near the “habitable zone,” the region in a planetary system where liquid water can exist on the surface of an orbiting planet. Although additional observations will be needed to reach that milestone, Kepler is detecting planets and possible candidates with a wide range of sizes and orbital distances to help scientists better understand our place in the galaxy.

The briefing participants are:

— Nick Gautier, Kepler project scientist, NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.
— Francois Fressin, lead author, Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.
— David Charbonneau, professor of astronomy, Harvard University
— Linda Elkins-Tanton, director of the Carnegie Institution for Science’s Department of Terrestrial Magnetism in Washington.

Full Story: http://www.nasa.gov/home/hqnews/2011/dec/HQ_M11-254_Kepler_Update.html