BIG SUN-DIVING COMET DISCOVERED: Astronomy forums are buzzing with speculation about newly-discovered Comet C/2012 S1 (ISON). Currently located beyond the orbit of Jupiter, Comet ISON is heading for a very close encounter with the sun next year. In Nov. 2013, it will pass less than 0.012 AU (1.8 million km) from the solar surface. The fierce heating it experiences then could turn the comet into a bright naked-eye object.
The orbital elements of ISON are so surprisingly similar to that of the Comet of 1680 that it has caused speculation in the astronomy community that the two bodies may have once been one comet. [...] This could develop into a “once in a lifetime” opportunity for spectators in the Northern Hemisphere to witness and photograph a truly great comet.
According to a number of articles that appeared at about the same time, the comet's orbit is taking it nearly directly at the Sun, and will get within 1.4 million kilometers of the Sun's surface in November of next year, which should provide a lot of heat to melt the surface and expel gas from the comet. By January, it will be about 60 million kilometers from Earth.
Comet brightness predictions sometimes exceed their performance. Amateur astronomers of a certain age may remember the Comet Kohoutek hype of 1973 – not quite the 'damp squib' it has been portrayed, since it reached naked eye visibility! Even if C/2012 S1 takes on the same light curve as Kohoutek it is certain to be spectacular, quite possibly a once-in-a-civilisation's-lifetime event.