Comet ISON shines in this five-minute exposure taken at NASA's Marshall Space Flight Center on Nov. 8. At the time, the comet was 97 million miles from Earth, heading toward a close encounter with the sun on Nov. 28. Located in the constellation of Virgo, it is now visible in a good pair of binoculars. (Photo: NASA/MSFC/Aaron Kingery)
Comet ISON's highly anticipated flyby of the sun is now just two weeks away, and scientists and skywatchers alike hope the encounter gives them another reason to be thankful this holiday season.
Comet ISON will skim just 730,000 miles (1.2 million kilometers) above the solar surface on Thanksgiving Day (Nov. 28) before heading out into deep space once again. If ISON survives this perilous plunge, the icy wanderer could put on quite a show in the ensuing weeks, becoming visible to the naked eye throughout much of December, experts say.
ISON was discovered by two Russian amateur astronomers in September 2012, giving scientists more than a year to gear up for its dramatic brush with the sun. Researchers have tracked the comet assiduously, training a number of ground- and space-based instruments on ISON as it barrels through the inner solar system. [Potentially Dazzling Comet ISON: 8 Essential Facts]
This NASA-organized Comet ISON Observation Campaign (CIOC) aims to gain a better understanding of ISON's composition, by noting which gases boil off the object at various distances from the sun.
"Another interesting facet of Comet ISON is that it appears to be a dynamically new comet, fresh from the Oort Cloud," CIOC officials write on the campaign's website. "This means it has probably never been through our solar system, and has never been subjected to the melting effects of solar radiation. It's a truly pristine example of early solar system material, and thus we are particularly eager to see the combined result of a 'raw' piece of solar system material being subjected to the sun's outer atmosphere!"
Nobody knows exactly what will happen during ISON's close solar encounter; it's tough to predict the behavior of any comet, especially dynamically new ones such as ISON, whose core is thought to be between 0.12 miles and 1.2 miles (0.2 to 2 kilometers) wide.
However, some scientists have voiced optimism that the object won't break apart, provided it has the density and rotational characteristics of a "typical" comet.
You don't have to wait until Thanksgiving to look for Comet ISON. The icy wanderer is visible in binoculars right now, streaking low in the predawn sky through the constellation Virgo. If you're interested in buying binoculars or a telescope to search for ISON, check out SPACE.com skywatching columnist Joe Rao's advice here.