So what is comet ISON and why does it have a strange name
ISON is an acronym for International Scientific Optical Network. It is a consortium of several countries to detect and track objects in space like comets, asteroids etc. This comet was named “ISON” because it was discovered using a 16″ telescope stationed near Kislovodsk, Russia. If you’d like its formal name, you may refer to it as C/2012 S1. The S1 suffix to the name is an indicator that it was discovered in September and 1 indicates that it was the first comet of the month.
Is ISON a threat to Earth?
Nope. The orbit of ISON has been determined. It is a sungrazer. That means that the come as close as 0.12 AU from the sun and about 0.4 AU from earth. For the uninitiated 1 AU is the mean distance between the sun and earth.
What’s so special about it
Comet ISON will make a very close pass to earth on 26th December 2013. The comet’s nucleus is large, about 5 Km wide, and will probably develop a large tail as it comes close to the sun. In short its a big comet that will be a treat to the eyes
How do I spot Comet ISON
Comet ISON is currently to dim to be noticed by the naked eye. Its about 12-13th magnitude, too dim to be noticed by small telescopes or binoculars, but easy to spot in larger telescopes and observatories. However in the coming months its set to brighten up significantly. For the enthusiast, click here for an ephemeris for the comet provided by Eyes on ISON India Campaign
To give you an idea about the progress of ISON’s brightness increase, here is a plot of its magnitude (both predicted and observed) over the past year. So far ground reports were somewhat disappointing, but this data from Lowell observatory suggests that the difference is not that far off. Even if ISON does not appear as bright as a Mag 0 star, it might still brighten enough to be a visual treat.