Posted: Thu, Nov 28, 2013, 9:11 AM ET (1411 GMT)
A comet that, for more than a year, has been billed by many as the "Comet of the Century" will make its closest approach to the Sun on Thursday, with astronomers watching to see if the comet survives the encounter. Comet ISON will reach perihelion at 1:37 pm EST (1837 GMT) Thursday, passing about 1.2 million kilometers from the Sun. NASA spacecraft, including the SOHO and STEREO spacecraft, will be observing ISON to see if it survives the close approach. If it does, the comet should be easily visible in early December as it heads out from the Sun. Since its discovery last fall, the comet was widely expected to be a brilliant object in the night sky, although it has not met those expectations so far during its approach to the Sun.
