Shiny new comet approaching: will ISON light up our skies?
There’s a new comet in the sky and we may be in store for a fabulous show from it later in 2013. It’s called Comet ISON, and was named in honor of the International Scientific Optical Network, (in Russian: Пулковская кооперация оптических наблюдателей), a cooperative of optical and radio observatories in ten nations that detect, monitor and track objects in space. It is managed by the Keldysh Institute of Applied Mathematics, part of the Russian Academy of Sciences. The new comet has been officially designated “C/2012 S1 (ISON).
The rapidly moving object was first seen in September 2012 by Vitali Nevski and Artyom Novichonok, two amateur astronomers from Russia. ISON is nearly 4 miles (6.5 kilometers) wide.
The majority of comets do not have tails, the glowing gases extending from the main rock, until they are flying through the area in-between Jupiter and Mars, the Asteroid Belt. They gain their tails due to being close enough to the sun for its heat to begin sublimating the water in the rocky comet body to gas.
Comet ISON, however, was seen having a tail by the time it was twice as far out from the sun as the belt. Scientists speculate that another material other than water was being sublimated from the comet into a tail.
The heavenly body might become the brightest comet seen on Earth for the rest of the 21st century, or it might fly by almost unseen, too dim to be observed with the naked eye. The telling time will be when Comet ISON is at its closest approach to the sun on November 28, 2013.
On that day, ISON’s head will be only 800,000 miles (1.2 million kilometers) from the surface of the sun. Should it not break up into pieces due to the heat and gravity, it will sling about the sun, shooting back on it long orbit to the outer solar system. It is just after it circles the sun that the fireworks may be seen from Earth.
Part of the excitement concerning the new comet is because it it thought to be on its initial orbit to the sun. This makes astronomers believe it will still retain much of it volatile substances. These are what heat up and are expelled from the core of the object and create the ephemeral tail of the comet. The tails can reach out for millions of miles behind the rapidly moving rock, creating a wondrous spectacle when seen from earth.
Come Thanksgiving time, 2013, we may all give thanks for a sighting of Comet ISON. In addition, by January 2014, the earth may possibly pass through a cloud of comet dust left in the wake of ISON.