Comet ISON, predicted to be brighter than a full-moon, and Comet PANSTARRS should combine to make 2013 the best year for observing comets in a very long time, maybe even a century or more.
In addition to the comets, 2013 is also expected to be a fantastic year for watching meteor showers.
Comet ISON is going to make its closest approach to the Sun, and be at its brightest, from around early November 2013 until mid-January 2014. By this point it is predicted to be brighter than the full moon in the nights sky, and to even be visible in broad daylight. And if it survives its initial approach to the Sun, it should emerge on its way back to the outer reaches of the solar system followed by an enormous tail that could stretch through a huge portion of the sky.
Part of the reason that ISON is predicted to become so bright is because of its parabolic orbit, which suggests that this may be its first time within the inner solar system, coming straight from the Oort Cloud.
There’s also the possibility that it was born from the same fragmented parent body as the the Great Comet of 1680, as the two seem to be following an incredibly similar path.
The Great Comet of 1680 was an incredibly bright comet that was visible throughout much of the year. It was known primarily for its enormous tail and for being bright enough to see in the middle of the day.
The Earth is also actually expected to pass through the tail that ISON leaves on its way out of the solar system on January 14-15, which may result in a large meteor shower.
Comet PANSTARRS isn’t expected to be as bright, but it will still be significant a comet. During it’s closest approach to the Sun, in March, it should be visible with the naked eye. March 5 will likely be its day of peak brightness, possibly getting as bright as magnitude -4, which is about as bright as Venus is. Though there is also the possibility that it may possess a large tail as many comets do.
Interestingly, Comet PANSTARRS appears to follow an enormously long orbit, taking millions of years to make it here from the Oort Cloud.
For those interested, here’s some more information on the Oort Cloud:
“The Oort Cloud is thought to be a remnant of the original protoplanetary disc that formed around the Sun approximately 4.6 billion years ago. The most widely accepted hypothesis is that the Oort cloud’s objects initially coalesced much closer to the Sun as part of the same process that formed the planets and asteroids, but that gravitational interaction with young gas giant planets such as Jupiter ejected the objects into extremely long elliptic or parabolic orbits. Recent research has been cited by NASA hypothesizing that a large number of Oort cloud objects are the product of an exchange of materials between the Sun and its sibling stars as they formed and drifted apart, and it is suggested that many – possibly the majority – of Oort cloud objects were not formed in close proximity to the Sun.”