Currently a faint speck in the night sky, Comet ISON (C/2012 S1) was only recently discovered. But as it emerges from the haze of the distant Oort Cloud and makes a close pass around our sun late next year, it could turn into the brightest comet anyone alive has ever seen, reports Sky & Telescope. During its closest approach to the Earth, in the weeks leading up to Christmas 2013, it could even be as bright as the full moon.


The comet will be made even more spectacular due to its close pass around the sun. At perihelion, or its closest approach, there will only be about 1.16 million miles between the comet and the sun's surface. This will cause an extreme melt-off of its ice, which will release gas and dust and form a gloriously long tail.


It will then make a relatively close swing past Earth just a few weeks after perihelion. At its closest, about 40 million miles from our planet, the sky should be moonless, which will only add to the comet's glow. Since all of this is set to occur around Christmas, it could be viewed as a miracle by some.


In fact, if all comes to pass as astronomers currently predict, ISON will be the most spectacular comet to grace Earth's skies since the Great Comet of 1680 (which supposedly caused the people of New York's Manhattan Island to be "overcome with terror at a sight in the heavens such as has seldom greeted human eyes.") In fact, it would likely be a once-in-a-civilization's-lifetime event.


Even more awe-inspiring, the comet is expected to pass very close to Mars in October 2013, which means NASA could snap pictures of it from the Martian surface using the Curiosity Rover's cameras.


On Earth, the comet should be visible to the naked eye from early November through the first several weeks of 2014. By comparison, that's not quite so long as Hale-Bopp was visible for back in 1997, but ISON is expected to be much brighter.


But having said that, it's good to point out that comet predictions don't always live up to expectations. Comet Kohoutek, for instance, was much-hyped but only dimly sputtered during its swing by Earth. Even so, astronomers say there are reasons to be optimistic. In fact, ISON appears to be on a trajectory eerily similar to that of the Great Comet of 1680. It's even possible that ISON and the Great Comet are fragments of the same parent body.


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Bryan Nelson ( @@brynelson ) writes about everything from environmental problems here on Earth to big questions in space.

Christmas 'miracle' comet could be as bright as the full moon
A newly discovered comet could offer a "once in a civilization" night-sky viewing opportunity that may not come again in our lifetime.