Comet Coming in 2013 May Be Brightest in Generations
A recently discovered comet is scheduled to come very close to the sun late next year and may get very bright, enough to outshine the full moon.
"Comet ISON … could be the brightest comet seen in many generations – brighter even than the full moon," British astronomer David Whitehouse said in The Independent.
But while astronomers are hoping for that "awesome" view of a bright comet, they say it's uncertain whether it will even survive as it nears the sun on Nov. 28, 2013.
"... Estimating comet brightness a year ahead of time is about like asking who's going to win the World Series next year. It could be astonishingly bright, or it could fizzle," said astronomer Bill Gray.
Comet 2012 S-1 ISON was discovered in September by Vitali Nevski of Belarus and Artyom Novichonok of Russia.
As to whether the comet poses a risk to Earth, NASA said it doesn't. While the comet's brightness is unpredictable, its orbit is already well understood. It will come to perihelion (closest approach to the Sun) on Nov. 28, 2013 at a distance of 0.012 AU (1.8 million km) from the center point of the Sun, according to NASA.
It will pass about 0.4 AU (60 million km) from Earth on Dec. 26, 2013.
What would make the comet brighten is the heat from the sun which will vaporize ices in its body, resulting in a tail that will be visible from Earth without telescopes from October to 2013 to January 2014, according to Reuters.
But, the comet could boil away completely when it gets close to the sun.
Gray gives it about a 30 percent chance of being a nice show and 60 percent chance of that being wrong.