I've been observing Comet ISON 2012 S1 for a couple of days short of one year. Now the real fun is about to begin!
At this point, September 28, 2013, Comet ISON S1 2012 has just entered the realm of the constellation Leo. It remains an object that is only seen through a telescope.
In early October, 2013, may break magnitude ten, becoming an object that will be visible through a binoculars. With the October 4th New Moon, we should have a couple of good weeks of viewing.
October 1, 2013 - Comet ISON will make its closes approach to Mars. NASA will turn the cameras of rovers Curiosity and Opportunity as well as the orbiters Mars Odyssey and Mars Reconnaissance onto the comet.
October 15, 2013 - By this time, the comet will be clearing the horizon by 3am - and by the dawn's light begins to glow, it will be 40 degrees high.
October 16, 2013 - The comet will be 2 degrees NNE of the star Regulus, the brightest star in the constellation Leo. This will make the still-dim challenge easier to locate and photograph. This should be a great day for viewing - the Full Moon begins does not enter the night sky until the 18th.
October 26, 2013 - Tonight's a photo op with the comet moving within three degrees of the three galaxies M96 M95 and M105.
Early November 2013 - Comet ISON should become a naked eye object.
November 3, 2013 - if anyone has an extra ticket to Africa, let me know. The annular-total eclipse will be visible there. So how cool will this be to see the comet during the eclipse?
November 7, 2013 - The comet will be less than a degree from the bright star Beta Virginis. This should make the comet easy to find in light-polluted areas.
November 14, 2013 - Another photo op: the Comet will be less than a degree from galaxy NGC 4697.
Mid-November, 2013 - the comet will be 20 degrees above the horizon at dawn, but hopefully the tail will be impressive.
November 17, 2013 - Full Moon: not a friend of viewing the comet.
November 18, 2013 - In spite of the Full Moon, the comet will be within half a degree of the star Spica, making the comet easy to find.
November 21, 2013 - The comet will be swallowed by the twilight from the sunrise. The comet will disappear for a while - unless (and the odds of this are low) it becomes visible in the daylight.
November 23, 2013 - The comet will be less than 5 degrees from Mercury and less than 5 degrees Saturn.
November 25, 2013 - Photo op with TWO comets. Comet ISON and Comet 2P/Encke will be within 1.2 degrees.
November 28, 2013, 2300 Universal Time - the comet reaches perihelion. In the days leading up to this, and immediately after, we'll see if the comet breaks apart or holds together. At this time the comet may become visible in the daylight. If the magnitude of the comet is minus 10, it may be visible. However, it will only be 1.5 degrees from the solar disk, so care will need to be taken in making observations.
December 5, 2013 - the comet will return to the predawn hours. It will have dimmed, but it is possible that it will be magnitude zero -- still impressive. If the comet was able to hold together during its closest encounter with the sun on November 28, the tail will be very, very impressive.
Mid-December, 2013 - the comet will be visible in BOTH early evening and early morning skies. It will be a third of the way up the sky in the morning, and low on the horizon in the evening. Since the comet will come so close to the sun, and since it will be making its first trip out of the Oort Cloud, there is every reason the view will be very dynamic.
January 2014 brings a great opportunity. The comet will remain visible all night long! However, at this point the comet will be dimming and at some time during the month the comet will reach a magnitude of 8 or so, meaning it will become something for the binoculars or the small telescope.
Oh -- one last note. It has been scientifically proven that comets and cats have two things in common. They both have tails and they both can be unpredictable.