Update on the 3 Dawn Comets:
The big news is how Comet ISON is turning into a flop instead of the brilliant showpiece comet.
Comet C/2013 R1 (LoveJoy):
This comet continues to slowly brighten up. Right now it's technically visible to the unaided eye although the author could not see it. This comet can easily be seen in handheld binoculars (such as 8 X 42) as a small, round, hazy blob. In the author's giant 20 x 80 binoculars; the comet has a large outer round head (Coma), a smaller bright inner spot (Nucleus), and a really short, faint tail. In a day or two, some sharp eyed individuals should be able to detect the comet as a faint, elongated, stain of light. For the rest of us, binoculars should reveal the comet. Comet C/2013 R1 (LoveJoy) is currently in the Constellation of Cancer. It will then move into the northern part of the Constellation of Leo during the rest of the November observing window. Comet LoveJoy is now the brightest and biggest of the Dawn comets.
C/2012 S1 (ISON):
This comet has really fallen behind predictions and is just barely brightening up. The comet is not visible in handheld binoculars and is difficult target even in giant binoculars. The comet is not expected to reach the threshold of unaided eye visibility in November. This comet is now the dimmest and smallest of the 3 Dawn comets.
Comet ISON is predicted to be a dim, dull, and small comet until the end of the month. Then there is a slight possibility that things could change for the better for this comet. On Nov. 28, the comet does a tight, close turn near the Sun and then quickly moves away from it. There are 3 possible outcomes of this close solar encounter.
There is considerable chance that the comet will not survive the solar turn. Only Option C gives the comet a very slim chance to brighten up. If the comet pulls away from the Sun, it should be visible in the bright glow of Dawn on 3 December 2013. The comet will be needed to be located with binoculars. Each Dawn, the comet will get higher in the sky but loses a little more of its brightness. By Dec. 9, the comet will have moved out of the bright Dawn light and into the darker skies. At that time there may be a slim chance of seeing the comet with the unaided eye. The comet will be in dark Pre-dawn sky until Dec. 14; then the Moon will ruin the view for the rest of the month.
So how big and bright would the comet get if it was "energized" by the Sun? Comets are notoriously hard to predict but the author's estimate is that if the comet survives, it would look similar to Comet C/2011 L4 (PanSTARRS). Comet PanSTARRS was a comet visible in our area in March of this year. You may recall that C/2011 L4 (PanSTARRS) was not a spectacular comet. Comet ISON will not be the comet of the century or the showpiece comet as first predicted. The comet may end up being only seen in giant binoculars or amateur size telescopes. Then again the odds are heavily stacked against the comet's survival.
This comet continues to brighten up very slowly as it heads towards the bright Dawn Twilight. The comet may just reach the threshold of unaided eye visibility just before it moves into the bright glare of Sunrise. The author's observations in his 20 x 80 giant binoculars reveal a small, fan shape comet. The comet is in the Constellation of Virgo. By Nov. 14, the comet will move into the bright glow of twilight. After Nov. 16, Comet 2P/ Encke will move into the glare of Sunrise and be lost from view. There's not much time left to observe Comet Encke.
Observing Window Time Period:
The time to observe the 3 Dawn Comets (the Observing Window) is until Nov. 15, 2013. After that the Moon will be in the morning sky and ruin the view for the rest of the month. Comet C/2013 R1 (LoveJoy) is up high enough that it can be seen in a dark sky. The other two comets are not that fortunate.
The next observing window will be in the first part of the month of December. This no Moon period for the Dawn sky is from 1 Dec thru 14 Dec 2013. After that the Moon will ruin the rest of the month. There is also a good chance that Comet LoveJoy may be the only comet visible in this observing window.
Optical Instruments for Observing the Comet(s):
Giant binoculars such as 11 X 70, 15 X 70, or 20 X 80 may be your best instruments for observing these comets (especially C/2013 R1 LoveJoy). Giant binoculars such as these need a firm, solid support like a tripod. Giant binoculars are really not made to be hand held.
Amateur size telescopes can be used to have some good views of the comet(s). Amateur Telescopes that have an objective aperture of 4" (100mm) to 6" (150mm) are ideal to look the bright comets with. A good low power (20X-50X), wide field eyepiece will give some nice views of the brighter comet(s).
The Eastern Dawn Skies necessary for observing these comet(s) may not be the most convenient time for some folk's schedule. The comet(s) are best seen in dark skies; well away from lights if possible. If you choose to observe these comet(s), just don't get your hopes and expectations up too high. Unfortunately Comet /2013 R1 (LoveJoy) isn't going to be a bright comet. The fate of Comet C/2012 S1 (ISON) is yet to be determined but its survival odds are not good.
Here's some nice links which can give you more information on the comet(s):
http://www.heavens-above.com/ (see comets section)
Gary T. Nowak
Vermont Astronomical Society