The best site for up-to-date comet viewing information is Seichi Yosida’s comet site here: http://www.aerith.net/comet/weekly/current.html
The screen shot below is the current posting from that site (used with permission) and shows comets above magnitude 12 or so that are presently in the sky. More details (including finder charts) about one or more of the comets (some possibly within binocular range) are provided below the table.
Comet Wirtanen for December 2018 and a NEW COMET for November!
Comet C/2018V1 Macholz-Fujikawa-Iwamoto
American astronomer Don Macholz has discovered another comet after a few hundred hours (over 700 actually) searching. The happy event occurred on Nov 7 and was also spotted by two Japanese comet hunters. Comet C/2018 V1 (Macholtz-Fujikawa-Iwamoto -henceforth Comet M-F-I) was just observed and it gives us another opportunity to spot a comet this year (along with Wirtanen which is also brightening on schedule -last estimate magnitude 7). Below is a finder chart from Starry Night. Comet C/2018V1 is a morning object in Virgo (note Venus and Spica as they appear Nov 22 am) and it is tracking eastwards (left) over the next few days as it gradually approaches the Sun. Click on chart to download a copy.
Look east at the start of morning twilight in the constellation Virgo. The comet is moving eastwards (above Venus) in Virgo and passes the planet on Nov 18 (only 10° from Venus at magnitude -4. The moon is nowhere in the sky at this time of morning and it is worth getting up before dawn to have a look. The comet should brighten perhaps to magnitude 5 or so as it approaches the Sun but it will also become lost in the glare by month end. Rounding the Sun in early December, it switches over into the evening sky and will perhaps be its brightest then. Comet M-F-I is not predicted to get as bright as Wirtanen but these objects are of course, unpredictable. The HOME page has information and the original S&T discovery article is here: S&T Comet K-F-I
More from Universe Today here: Comet M-F-I
Comet 46/P Wirtanen in Dec 2018
Comet 46/P Wirtanen is the second of the pair of naked eye comets expected in 2018, but this one peaks late in the year around December. There are Moon-free periods to seek it out in the first two weeks of December and it has a nice close approach to the Pleiades on Dec 16 (Moon is just past FQ, however). This comet will be well placed in the sky during dark hours and becomes circumpolar and visible in the sky all night long from Christmas into the new year. It should still be bright on the moon-free nights in the first two weeks of January and February as well. One prediction for brightness (Seichi Yoshida) indicates magnitude 3 for Jan 2019!
The map below shows the path of 46/P during its time in our sky from Dec 01 to Dec 25, 2018. The chart is from Starry Night. Click on it to download a copy.
Comet Wirtanen Update:
Comet 21/P Giacobini-Zinner was around in Sep 2018 (last look at Frank’s image below…)
Periodic Comet 21/P Giacobini-Zinner appeared on schedule and did not overwhelm observers. However, Frank Williams sent in this amazing shot of Comet 21P taken during Starfest from his observatory in Allenford. He used his refractor (140 mm Tec) and a Canon 6D camera. Image is a stack of two 3-minute shots of the comet plus 37 one-minute images. He used Pixinsight for the processing. Total exposure time was 43 minutes.
Frank Williams Comet 21P/ 43 minutes total exposure (140 mm refractor)
New Comet discovered by PanSTARRS waaaaaayyy out there beyond Saturn! [One to look forward to in 2022]
A brand new comet has been spotted by the Hubble Space Telescope, and remarkably, even though it is still far enough away from the Sun that its water ice would be as hard as rock, it is already showing signs of activity.
That makes this new comet, called C/2017 K2 (PANSTARRS), or just K2 for short, the farthest active comet astronomers have ever seen - at a distance of 2.4 billion kilometres from the Sun, which is beyond the orbit of Saturn.
Discovered in May in 2017, using Hawaii's Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), astronomers used the Hubble Space Telescope to get a better look at "K2".
Hubble revealed that the comet's coma - the gassy, dusty "atmosphere" that surrounds the comet's solid nucleus - was already around 115,000 km across. That's roughly the diameter of the planet Saturn! Closest approach to the Sun is predicted for 2022.
Read more about it here: Comet K2 (PanSTARRS)
Our Next Great Comet is OVERDUE!
Tim Reyes writes for EarthSky.org. One of his recent excellent articles is called "When is Our Next Great Comet?" An interesting read! [Maybe it will be Comet C/2017 K2 PanSTARRS , see above].