Comet 2011 L4 (PANSTARRS), like 2007's Comet McNaught (left), will first appear in the skies of one hemisphere, but achieve its greatest brilliance in the other. McNaught was briefly an actual daylight comet in the Northern Hemisphere, but reached its true glory in the South. But this time, we in the Northern Hemisphere get the big show!
Comet PANSTARRS- discovered through the Panoramic Survey Telescope and Rapid Response System in Hawaii- wlll be visible in the Southern Hemisphere in January and February of next year, but move across the equator around the middle of March as a (hopefully) very bright object in the evening twilight sky. It is then that it will reach its perihelion (its closest approach to the sun- and hopefully its greatest brilliance) around the middle of the month. After that, it will slowly fade as it moves higher in the sky. It should still be fairly bright and quite visible at Easter, March 31. It will probably no longer be visible to the naked eye when it approaches Polaris in May.
Comets Hyukatake and Hale-Bopp also graced our skies around Easter. I'm not sure what connection, if any, exists between the Festival of the Resurrection and the appearance of recent great comets, but the statistical correlation is interesting.
Comet 2012 S1, aka Comet ISON, is also headed our way, due between November of next year and February of 2014. It was recently discovered by Vitali Nevski of Belarus and Artyom Novichonok of Russia on September 21 using the reflector telescope at the International Scientific Optical Network (ISON) near Kirslovodsk, Russia. Why it isn't being called Comet Nevski-Novichonok, I don't know. More and more satellites, telescopes, and other non-human instruments are making the discoveries, and thus getting the credit. But in this case, actual astronomers were involved.
Anyway, the apparent orbit of Comet ISON reminds astronomers of the Great Comet of 1680, one of the brightest comets of all time. Speculation is that ISON might be as bright as, or even brighter than, the full moon!
As one who missed Comet McNaught and has been kicking himself ever since, I, for one, am looking forward to re-living the excitement of the Hyukatake/Hale-Bopp double-header of 1996-97 with another cometary twin bill, this time even closer together.
Of course, one shouldn't count one's comets until they reach perihelion. As an astronomy- besotted kid, I somehow missed Comet Arend-Roland in 1957. I also missed Comet Seki-Lines in 1962; I didn't hear about it until it was far too late. The same thing happened with 1965's Comet Ikeya-Seki, a "sun-grazer" which apparently put on a fine show before it broke apart as it approached perihelion. Once again, I didn't hear about 1970's Comet Bennett in time. So as 24 year-old, I was really hyped at the prospect of what was billed as "the Comet of the Century," Comet Kohoutek, in 1974. But it failed to brighten as expected, and remained invisible from my home inside the city limits of Chicago.
After having been "burned" by the Kohoutek fiasco, the media didn't give much attention to 1975's Comet West- which also broke up near perihelion, but also put on a spectacular show beforehand. What is especially galling is tht I was working at the time as a night watchman in an office building in Chicago's Loop with a spectacular view of Lake Michigan- which, if I'd only known to look, would have afforded a spectacular view of this great comet at its best.
1986's apparition of Comet Haley, to which I had looked forward all my life (despite warnings that it would be a dud) lived down to expectations. It was a mere smudge in the sky even in binoculars.
In 1990, Comet Austin imitated Kohoutek by fizzling after arousing great expectations. I was getting pretty tired of waiting to see my first great comet. But then came the discovery of Hale-Bopp, followed by the announcement of Hyukatake, which arrived almost exactly a year before it. Hyukatake was a ghostly blue object with a long tail that reached most of the way across the sky. Hale-Bopp was a bright, more compact comet with a distinct blue ion tail along with its dust tail. Observing each through a variety of binoculars (the instrument of choice for cometary observation) and telescopes was a joy well worth the wait. The advent of Comet Hyukatake re-stimulated my interest in astronomy, and I joined the Des Moines Astronomical Society, whose Ashton Observatory provided both a somewhat dark location and a wide variety of resources fot the task.
I was excited by the discovery of Comet McNaught, especially since I was teaching a course on Astronomy, Space Travel and Science Fiction for the Saturday Institute of the Des Moines Public Schools Talented and Gifted Program at the time. But I knew that the best part of the show was going to be reserved for the Southern Hemisphere, and even when I heard that it had become visible in the daytime here in Des Moines I procrastinated until the opportunity to see it had passed. I was amazed at how may of my students hadn't even known about Hyukatake and Hale-Bopp. It's hard to see how anybody who was outside after dark during their peaks could have missed them, but apparently plenty of people did. And after all, I myself have a long record of somehow managing to miss great comets.
Three years ago Comet Elenin looked like a sure-fire naked eye comet sure to dazzle us all. Unfortunately, it self-destrcuted instead.
Last year Comet Lovejoy met all the qualifications of a great comet except one: it was so close to the sun when it reached its perihelion that the best part of the show was invisible from Earth.
So I feel like I"m overdue for another great comet or two. And even bearing in mind the substantial chance that one or both of the new comets will fizzle, I'm hyped once again.
So get yourself a pair of 7x50 binoculars- if you're under 30. Otherwise 10x50 binoculars are the way to go; most people's pupils no longer expand far enough after age 30 to make use of seven mm exit pupils, and the additional magnification is a better use of the weight.Even if both PANSTARRS and ISON fizzle like Comets Kohoutek and Austin, a new great comet will be here eventually- and you'll find it's well worth the investment, as well as the wait.
HT: Tom's Astronomy Blog,
Astro Bob
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