Comet ISON was discovered over a year ago - and since then, it has been the subject of much discussion and debate. At one point, it was named the "Comet of the Century" as there were predictions that it would be as bright as the Full Moon. Comets become brighter as they near the Sun - they warm up and the surface ice melts, releasing dust and gasses which form a long, bright comet tail. Comet ISON did not keep up with the predictions and astronomers realized that the comet may not put on a show at all.
The comet will complete a 25,000 year trip this weekend which started far beyond the outer planets and will end as it rounds the Sun. Passing just over one million kilometres above the Sun's surface, it will be exposed to tremendous temperatures. Everyone will be watching to see if it survives the trip.
Over the past few weeks, Mississauga astronomers and sky watchers have been rising early to see the comet rise ahead of the Sun in the eastern sky.
Local avid amateur astronomer Chris Malicki - who is also the Secretary for the Mississauga Centre of the Royal Astronomical Society of Canada - Mississauga's local astronomy club - observed Comet ISON and another comet - Comet Lovejoy - from the shore of Lake Ontario at Jack Darling Park on November 14. He wrote:
It was a beautiful clear morning 6 a.m. Nov. 14. Comet Lovejoy, above the sickle of Leo was high up and very easy with 10x50 binoculars. The comet was an oval glow with a hint of a broad short tail. I then drove to Jack Darling Park, to “eclipse point” (where we observed the eclipse on Nov.3) and easily found Comet ISON between Spica and gamma Virginis. ISON was much smaller than Lovejoy but had quite a brighter nucleus – It reminded me of a globular cluster – bright, fuzzy, no tail. It was a bit brighter than the 6.26 mg star nearby, so I estimate ISON at mag 6. Happy to see 2 new comets in one morning.
After Comet ISON swings around the Sun on November 30, it should appear again in the early morning sky as it heads back on its long journey. There are some concerns that it may break up and not be visible. So astronomers will be watching the comet closely this weekend. There are NASA spacecraft in space which constantly observe the Sun. These spacecraft should provide a good view of the comet as it swings around the Sun.
If Comet ISON survives the trip, comet watchers in Mississauga will have a good opportunity to view the comet as it rises in the east over the lake. See the diagram below for positions of the comet and watch this blog for updates.