What is Comet ISON, possible 'comet of the century,' doing now?
Scientists have observed that 2.2 million pounds of gas per day is fizzling off the comet as it continues its much-watched journey toward the sun.
ESA/Hubble Heritage Team/NASA/Reuters
Comet ISON is being watched.
As part of the Comet ISON Observing Campaign, astronomers fixed NASA's Spitzer Space Telescope on Comet ISON for 24 hours on June 13th. The results now show carbon dioxide emissions from the comet, which is expected to make a much anticipated journey within several thousand miles of the sun to become – maybe – one of the world's most famous comets.
Scientists believe that about 2.2 million pounds of the gas per day is fizzling off the "soda-pop comet,” drawing behind the comet a tail about 186,400 miles long. The stream is also made of the some 120 million pounds of dust that the comet loses each day.
That tail is expected to get even longer and brighter – if the comet survives long enough for that to happen.
ISON, a "sungrazer” comet, is expected to pass within 750,000 miles of the sun on November 28, 2013. There, it could disintegrate in the sun’s broil and radiation, as do so many comets that dare to come too close.
"Think of ISON as a big block of ice, and if it is not large enough, it will all melt and then boil away," said Carey Lisse, leader of NASA's Comet ISON Observation Campaign and a senior research scientist at the Johns Hopkins University Applied Physics Laboratory.