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               Comet of the Century' Already May Have Fizzled Out

   by Reuters

   Astronomers slated to meet this week to discuss observing plans for
   Comet ISON may not have much to talk about. The so-called "Comet of the
   Century" may already have fizzled out.

   "The future of comet ISON does not look bright," astronomer Ignacio
   Ferrin, with the University of Antioquia in Colombia, said in a
   statement on Monday.

   Ferrin's calculations show the comet, which is currently moving toward
   the sun at 16 miles (26 km) per second, has not brightened since
   mid-January. That may be because the comet is already out of ice
   particles in its body, which melt as the comet moves closer to the sun,
   creating a long, bright tail.

   Another theory is that the comet is covered in a layer of silicate dust
   that snuffs out water vapor and other gasses that brighten the comet.

   "Comet ISON has been on a standstill for more than 132 days ... a
   rather puzzling feat," Ferrin wrote in a paper submitted to the Monthly
   Notices of the Royal Astronomical Society and posted online at the
   archival site [1]arXiv.org.

   The comet, named ISON for the International Scientific Optical Network
   that made its discovery, was found in September 2012 by two amateur
   Russian astronomers.

   It is due to pass about 724,000 miles (1.2 million km) from the sun on
   Nov. 28. The relatively close pass was expected to create a massive
   tail that some scientists predict will be visible even in daylight.

   If it survives, that is. At that distance, the comet would reach
   temperatures of about 4,900 degrees Fahrenheit (2,700 degrees Celsius)
   - hot enough to melt lead. It may also be pulled apart by the sun's
   gravity.

   Scientists believe the comet hails from the Oort Cloud, a cluster of
   icy rocks that circle the sun about 50,000 times farther away than
   Earth's orbit. Calculations show Comet ISON is making its first - and
   possibly last - voyage into the inner solar system.
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   [2]http://www.voanews.com/content/reu-comet-of-the-century/1712644.html

References

   1. http://arxiv.org/
   2. http://www.voanews.com/content/reu-comet-of-the-century/1712644.html