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Hubble Breaks Record For Furthest Supernova

April 4, 2013 1 comment

Credit: NASA, ESA, and Z. Levay (STScI)

Credit: NASA, ESA, and Z. Levay (STScI)

The NASA/ESA Hubble Space Telescope has broken the record in the quest to find the furthest supernova of the type used to measure cosmic distances. This supernova exploded more than 10 billion years ago (redshift 1.914), at a time the Universe was in its early formative years and stars were being born at a rapid rate.

The supernova, designated SN UDS10Wil [1], belongs to a special class of exploding stars known as Type Ia supernovae. These bright beacons are prized by astronomers because they can be used as a yardstick for measuring cosmic distances, thereby yielding clues to the nature of dark energy, the mysterious force accelerating the rate of expansion of the Universe.

“This new distance record holder opens a window into the early Universe, offering important new insights into how these supernovae form,” said astronomer David O. Jones of The Johns Hopkins University in Baltimore, Md., lead author on the science paper detailing the discovery. “At that epoch, we can test theories about how reliable these detonations are for understanding the evolution of the Universe and its expansion.”

One of the debates surrounding Type Ia supernovae is the nature of the fuse that ignites them. This latest discovery adds credence to one of two competing theories of how they explode.

Full Story and Images: http://www.spacetelescope.org/news/heic1306/
Also: http://hubblesite.org/newscenter/archive/releases/2013/11/full/
Also: http://www.nasa.gov/mission_pages/hubble/science/sn-wilson.html
Also: http://releases.jhu.edu/2013/04/04/farthest-supernova/

International Dark Sky Week 5 – 11 April, 2013


IDSW_smCelebrate the stars! Created in 2003 by high-school student Jennifer Barlow, IDSW has grown to become a worldwide event and a key component of Global Astronomy Month. The goals of IDSW are to appreciate the beauty of the night sky and to raise awareness of how poor-quality lighting creates light pollution.

Light pollution is a growing problem. Not only does it have detrimental effects on our views of the night sky, but it also disrupts the natural environment, wastes energy, and has the potential to cause health problems.

Full Story and Important Links: http://www.darksky.org/resources/109-international-dark-sky-week

NASA Team Investigates Complex Chemistry At Titan


Image credit: NASA/JPL-Caltech/Space Science Institute

Image credit: NASA/JPL-Caltech/Space Science Institute

A laboratory experiment at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., simulating the atmosphere of Saturn’s moon Titan suggests complex organic chemistry that could eventually lead to the building blocks of life extends lower in the atmosphere than previously thought. The results now point out another region on the moon that could brew up prebiotic materials. The paper was published in Nature Communications this week.

“Scientists previously thought that as we got closer to the surface of Titan, the moon’s atmospheric chemistry was basically inert and dull,” said Murthy Gudipati, the paper’s lead author at JPL. “Our experiment shows that’s not true. The same kind of light that drives biological chemistry on Earth’s surface could also drive chemistry on Titan, even though Titan receives far less light from the sun and is much colder. Titan is not a sleeping giant in the lower atmosphere, but at least half awake in its chemical activity.”

Scientists have known since NASA’s Voyager mission flew by the Saturn system in the early 1980s that Titan, Saturn’s largest moon, has a thick, hazy atmosphere with hydrocarbons, including methane and ethane. These simple organic molecules can develop into smog-like, airborne molecules with carbon-nitrogen-hydrogen bonds, which astronomer Carl Sagan called “tholins.”

Full Story: http://www.jpl.nasa.gov/news/news.php?release=2013-120
Also: http://www.nasa.gov/topics/solarsystem/features/titan20130403.html

Green Pea Galaxies Could Help Astronomers Understand Early Universe


The rare Green Pea galaxies discovered by the general public in 2007 could help confirm astronomers’ understanding of reionization, a pivotal stage in the evolution of the early universe, say University of Michigan researchers.

Reionization occurred a few hundred million years after the Big Bang as the first stars were turning on and forming the first galaxies. During this period, the space between the galaxies changed from an opaque, neutral fog to a transparent charged plasma, as it is today. Plasma is gas that’s electrically charged.

As for how this happened, the prevailing theory holds that massive stars in the early galaxies produced an abundance of high-energy ultraviolet light that escaped into intergalactic space. There, the UV light interacted with the neutral hydrogen gas it met, blasting electrons off the hydrogen atoms and leaving behind a plasma of negatively charged electrons and positively charged hydrogen ions.

“We think this is what happened but when we looked at galaxies nearby, the high-energy radiation doesn’t appear to make it out. There’s been a push to find some galaxies that show signs of radiation escaping,” said Anne Jaskot, a doctoral student in astronomy.

Full Story: http://www.ns.umich.edu/new/releases/21352-green-pea-galaxies-could-help-astronomers-understand-early-universe

Astronomers Anticipate 100 Billion Earth-Like Planets


Researchers at The University of Auckland have proposed a new method for finding Earth-like planets and they anticipate that the number will be in the order of 100 billion.

The strategy uses a technique called gravitational microlensing, currently used by a Japan-New Zealand collaboration called MOA (Microlensing Observations in Astrophysics) at New Zealand’s Mt John Observatory. Their work will appear in the Oxford University Press journal Monthly Notices of the Royal Astronomical Society.

Lead author Dr Phil Yock from the University of Auckland’s Department of Physics explains that the work will require a combination of data from microlensing and the NASA Kepler space telescope.

“Our proposal is to measure the number of Earth-mass planets orbiting stars at distances typically twice the Sun-Earth distance. Our planets will therefore be cooler than the Earth. By interpolating between the Kepler and MOA results, we should get a good estimate of the number of Earth-like, habitable planets in the Galaxy. We anticipate a number in the order of 100 billion.”

Full Story: http://www.ras.org.uk/news-and-press/224-news-2013/2239-astronomers-anticipate-100-billion-earth-like-planets