If you haven’t heard, a new comet was recently spotted. Even better, it’s expected to pass ridiculously close to earth in 2013 and, if those predictions prove true, it will put on quite a show in our night sky. The new object goes by the catchy name of of C/2012 S1, but is generally being called ISON.
The projected orbit should take ISON directly towards the sun in November 2013, causing melting which will result in a very defined tail. By January 2014 it should pass 60 million kilometers from Earth, and that combination of large tail and proximity to earth could result in a night sky object approximately as bright as the moon. That would make ISON the brightest comet ever seen.
According to a NASA report, “comet researcher John Bortle has pointed out a curious similarity between the orbit of Comet ISON and that of the Great Comet of 1680. ‘Purely as speculation,’ he says, ‘perhaps the two bodies could have been one a few revolutions ago.'”
All of this is still somewhat unknown because, for one thing, the brightness will depend on the composition of materials making up the comet and how much melting actually occurs. However, the best estimates at this point are leaning towards a best-case scenario for anyone interested in the night sky.