LOS ANGELES, CA (Catholic Online) – The most anticipated comet of the century is now approaching the orbit of Mars and will pass close enough to the Red Planet to be imaged by a telescope by the Mars Reconnaissance Orbiter around the planet, or the Curiosity rover on the surface. When it happens, it will become the first comet to be photographed from Mars.
Comet ISON is approaching the “frost line” which is the point where water vapor will sublimate from the surface causing the comet to appear mush brighter than its current magnitude of 13. The brighter the comet, the easier it will be to spot.
Already, as the comet warms it has cast off dust and vapor allowing astronomers to capture images of the swift visitor to our inner solar system.
For observers on the ground, a telescope of 10 inches or better diameter, should be able to resolve the object under dark-sky conditions. Intrepid viewers will need to be out just before dawn, and should look for ISON to the left of Mars as a faint, fuzzy patch.
Even in the large scopes, the comet is difficult to see and looks like a puff of cloud against the black of space.
This tiny patch will brighten however, and will put on a display like none other in decades, or so astronomers hope.
In November, ISON will brighten enough to be visible to the naked eye. Billions of people will see the comet just as it races towards its close approach to the Sun on Nov. 23. On that day, the comet will whip around the Sun, less than a million miles from its surface.
What happens next is a guess. The comet may break apart and fizzle out in the heat of the sun, or it may survive and cast off spectacular volumes of vapor, brightening so much that it rivals the full moon in the sky.
For a few days at least, the comet could even be visible under daylight.
However, this is the range of predictions, based on its size and close approach to the Sun. Other comets have done similar things with widely varied results. Much depends on the composition, size, and quality of the comet. It is believed ISON is a first-time visitor to the inner solar system, so it should be brighter than others which have already lost much of their vapor through repeated passes by the Sun.
Also, ISON is on a trajectory to leave the solar system after it buzzes the Sun in November. The comet is confirmed to be on an “ejection” trajectory meaning that it will fly out into deep space and never return to the solar system again.
It will only be a matter of time before another dramatic comet graces our skies. Comets are actually common visitors to the inner solar system, and there are at least a few taking aim at the Sun at any given time. However, only a few comets in a decade are bright enough and close enough to be seen with the naked eye on Earth.
Only one in centuries is bright enough to see during the day, but they do occur, and will occur again.
For skywatchers with large telescopes, it’s time to start looking. For the rest of us, we have just weeks to go before we can see the skyshow of a lifetime.