How to spot Comet ISON now

The comet of the century may be barreling toward Earth and holds the promise of a spectacular display. Here's how to see this remarkable object and what to expect.

LOS ANGELES, CA (Catholic Online) - Comet C/2012 S1 (ISON), simply dubbed Comet ISON in the media, was discovered on September 21 beyond the orbit of Jupiter, and almost immediately created a sensation in the astronomical community. The comet holds the promise of becoming so bright that it may be visible in the daytime sky.

Amateur Russian observers, Vitali Nevski and Artyom Novichonok, working as part of the International Scientific Optical Network (ISON) discovered the comet. Quick observations revealed that its orbit is highly parabolic; meaning it will plunge very near the sun, then head straight back out into the distant solar system - provided it survives its close solar approach.

In October, the comet will pass close to Mars and scientists will attempt to photograph it from around the Red Planet the using the cameras on the Mars Reconnaissance Orbiter.

At its closest to the sun, Comet ISON will be just 1.8 million kilometers from the solar surface, or just over one million miles. This is extremely close, and some comets that pass that close do not survive the approach, breaking up and melting into the solar wind instead.

The great question for Comet ISON, is whether or not it will survive this fiery brush with the sun. Assuming it survives, it will likely become extraordinarily bright and visible, even in the daytime sky. It's chances are fair, as comets often survive even closer approaches than this. After approaching the sun, the comet will next pass near us, just 40 million miles from Earth.

Comet's ISON's odds cannot be predicted since this is almost certainly the first time it has entered the inner solar system from its likely origin in the Oort cloud. The Oort cloud is a halo of comets believed to exist at the distant edge of the solar system, remnants of creation. Scientists believe that occasional gravitational perturbations can knock these comets out of their distant orbits and send them falling towards the sun.

As an added bit of trivia, scientists think the comet could be a relative of one that became known as the Great Comet of 1680. That comet was also visible in the daytime sky. Scientists suspect this because the orbits of both objects appear to be very similar, although data from 1680 is not as accurate as today's measurements. It is even possible the comet could be the same one, although this is less likely because ISON's orbit appears to be very long.

Secret Archives of the Saints, Subscribe Today

However, the anticipated brightness of Comet ISON will be a direct result of its intense heating rather than parentage. Since comets are partially comprised of frozen liquid, typically water, the heating releases vapor into space around the comet's nucleus. The water vapor reflects more light than the surrounding dust, which makes the comet's tail appear very bright.

Scientists estimate the comet may become brighter than the full moon, which would make it visible in the daytime sky.

The comet should be visible to the naked eye starting sometime in late October or early November, and will remain visible, if it survives, until January 2014. After that it will return to the outer solar system, where it will probably remain for several thousand years, judging from its extreme, parabolic orbit.

To view the comet, one will merely have to look in the direction of the sun, although viewers must only use their eyes, and not optical aids such as telescopes and binoculars, for safety reasons. The comet will be very obvious in the sky, appearing as a bright fuzzy patch, likely with a long, diffuse tail pointing away from the sun.

There is, of course, one value-added bonus that may come with the comet. Earth will pass through ISON's orbit inviting the possibility of a new meteor shower around January 14-15, 2014. Meteor showers are produced when Earth passes through the orbits of comets, even if the comets are hundreds or thousands of years distant. This is because comets tend to repeat their orbits over millions of years, constantly adding dust in their wake.

Comet ISON will be the second of two comets that should be visible to the naked eye in 2013. In March, the comet C/2011 L4 will be easily visible through binoculars and probably reach naked-eye visibility for a short time as it passes near the sun.

Anyone wishing to view Comet ISON now, will need a large telescope, a dark sky, and a chart to locate the object, which is presently too dim to see otherwise. The comet is in the constellation Gemini, moving towards Cancer. It will probably become visible to 8-10 inch scopes sometime in September. The star chart in the image shows where to look.

---

'Help Give every Student and Teacher FREE resources for a world-class Moral Catholic Education'