Last updated: November 28, 2020

This page will list all the comets that I am currently observing, in west-to-east order from low in the western evening sky to low in the eastern morning sky. It will provide brief information about a comet's location, motion, and current brightness at the time of the update, as well as, when appropriate, notes about potential future activity. The page will also list any asteroidal objects I am following that might potentially be comets, and for the benefit of comet observers in the southern hemisphere it will also list those comets (and other objects) that are bright enough for observation but that are not accessible from the northern hemisphere. Comets (and other objects) that are expected to be 9th magnitude or brighter (and that are also easily accessible for observation) at the time of the given update will be highlighted in red print. Orbital elements and ephemerides for the comets and other objects listed here can be obtained via the Minor Planet Center's Ephemeris Service or via JPL Horizons. I expect to update this page on approximately a bi-weekly basis.


Comet 88P/Howell (no. 678)

Now two months past perihelion passage, this comet is gradually fading but thus far has maintained its brightness rather well, being near magnitude 10 1/2 during my most recent observations earlier this month. As has been true for the past several weeks it remains fairly low in my southwestern sky after dusk, being presently located in southern Capricornus four degrees northwest of the star Psi Capricorni; it is traveling towards the east-northeast at approximately 50 arcminutes per day, passing half a degree south of the star Eta Capricorni on December 8 then 40 arcminutes south of the star Gamma Capricorni on December 19 and half a degree south of the star Delta Capricorni three days later. Based upon its behavior during previous returns, the comet should now be starting to fade more rapidly, although I expect to be able to follow it until near the end of this year.

Comet 156P/Russell-LINEAR (no. 686)

Having passed through perihelion a week and a half ago, this comet has maintained the overall appearance it has exhibited ever since I first picked it up, i.e., a small and "dense" inner coma surrounded by a faint and diffuse outer coma, and has also brightened somewhat, being near magnitude 11 1/2 when I last observed it earlier this month. It is currently located in western Pisces 20 arcminutes northeast of the star Omega Piscium and is traveling towards the northeast at approximately 50 arcminutes per day, passing two degrees east of the star Gamma Pegasi (the southeastern "corner" of the "Great Square" of Pegasus) on December 11. Without any knowledge of its brightness behavior it is difficult to know what to expect during the coming weeks, but since the comet is now receding from the sun as well as Earth it will most likely commence fading, although this could be quite gradual and it may well remain visible for a few more weeks.

Comet 11P/Tempel-Swift-LINEAR (no. 689)

My tally's most recent addition appeared as a very faint, vague, diffuse object of 14th magnitude during my initial observations in mid-November. Since it was closest to Earth (0.49 AU) early this month and has just passed through perihelion, it is distinctly possible that it has already been as bright as it is going to get and thus may soon fade beyond visual range (if it hasn't already done so); indeed, some recent images I have seen seem to suggest this. On the other hand, since almost nothing is known about this comet's current brightness behavior it is at least conceivable that, like some other short-period comets, it may exhibit some asymmetry in that behavior and accordingly may brighten some over the next couple of weeks. It is currently located in central Pisces a little over eight degrees southeast of the star Gamma Pegasi (and just south of the star 58 Piscium) and is traveling towards the east-southeast at 40 arcminutes per day.

Comet 29P/Schwassmann-Wachmann 1 (no. 498)

After being relatively quiet and inactive for several weeks, this comet underwent a new outburst just over a week ago, and I successfully observed it the following night as a small and condensed object of magnitude 13 1/2. Images I've seen that were taken since then suggest that it is following the pattern it ususally exhibits after the onset of an outburst, i.e., the coma is gradually growing larger and more diffuse, which it should continue to do over the next two to three weeks before eventually fading out. Meanwhile, as is always possible with this comet, additional outbursts could take place at any time. It went through opposition early this month and is currently located in northern Aries four degrees northeast of the star Alpha Arietis (Hamal), and is traveling towards the west-southwest at a relatively slow 6 arcminutes per day.

Comet 398P/Boattini P/2020 P2 (no. 688)

This relatively recent addition to my tally remained near 14th magnitude during my initial observations earlier this month, although it did exhibit some distinct brightening during that time; it appeared as a moderately condensed object slightly less than an arcminute across when I last observed it. It is currently located in northern Eridanus four degrees northwest of the star Iota Eridani and is traveling towards the northeast at slightly under 10 arcminutes per day, although in coming weeks it curves more towards the north-northeast and accelerates, to 25 arcminutes per day by mid-December. The comet was just at opposition two days ago and meanwhile is approaching both the sun and Earth, and I expect it to brighten by at least a magnitude or more over the next few weeks.

Comet ATLAS C/2020 M3 (no. 685)

Now almost five weeks past perihelion, this comet was nearest Earth (0.36 AU) two weeks ago and has maintained its overall brightness and appearance rather well for the past few weeks, being visible in 10x50 binoculars near 8th magnitude and exhibiting a large diffuse coma, which I measured as being 15 arcminutes across when I most recently observed it. Since it is now receding from both the sun and Earth it may begin to fade within the not-too-distant future, although I suspect it will remain relatively bright and easy to observe for at least a few more weeks. The comet is currently located in eastern Taurus three degrees west-northwest of the star Zeta Tauri (and two degrees west of the Crab Nebula M1) and is traveling almost due northward at 70 arcminutes per day (slowing down to 40 arcminutes per day by mid-December); it crosses into Auriga on December 4 (passing 40 arcminutes west of the star Beta Tauri as it does so) and is at opposition a week later, at which time it will be one degree east of the "Flaming Star Nebula" IC 405.

Comet P/Scheila P/(596) (no. 669) 

Slightly over one year has now elapsed since I added this one-time "active asteroid" to my tally on its current "return." It has emerged into the morning sky over the past couple of months and, as expected, has appeared completely starlike during my recent observations, being just fainter than magnitude 14 1/2 during my most recent observation. It is currently located in northwestern Leo two degrees northwest of the star Mu Leonis and is traveling towards the east-northeast at somewhat under 10 arcminutes per day; over the next few weeks it curves more northerly and slows down as it approaches its stationary point in late December. Scheila should brighten gradually over the near-term future, eventually reaching magnitude 13.5 when at opposition in early February 2021.

Comet ATLAS C/2019 N1 (no. 681)

After being in conjunction with the sun last month, this comet has now begun emerging into the morning sky, and I successfully picked it up very low in my southeastern sky at the beginning of dawn three days ago, as a difficult and small somewhat condensed object of 12th magnitude. It is presently located in southern Virgo two degrees south-southeast of the star 89 Virginis (and 11 degrees southeast of the bright star Spica) and is traveling towards the south-southeast at approximately 40 arcminutes per day; it crosses into eastern Hydra on December 2 and passes just 10 arcminutes west of the star Pi Hydrae seven days later. The comet is at perihelion in three days and is also approaching Earth, and thus may brighten marginally over the near-term future, however it remains low in my southeastern sky before dawn, and with its increasing southerly declination (going south of declination -30 degrees on December 14 and south of -40 degrees two weeks later) I will lose it below my southern horizon before too much longer.

Comet Erasmus C/2020 S3 (no. 687)

I am very probably finished with this comet, as it is now getting very low in my southeastern morning sky; its elongation drops below 30 degrees today (with its being located in eastern Hydra four degrees north-northeast of the star Pi Hydrae and traveling just southward of due east at over two degrees per day) and below 25 degrees on December 2, and thus it will soon disappear into the dawn. After a rather rapid rise in brightness over the past couple of months its rate of brightening has recently leveled off, and the comet has remained close to 7th magnitude for the past week or so (being rather easily visible in 10x50 binoculars as a small condensed object, and with up to 15 arcminutes of an ion tail being visible telescopically). Perihelion passage is now just two weeks away, and two days later (December 14) the comet will be located 11 degrees west of the sun during that day's total solar eclipse; depending upon how it might (or might not) brighten between now and then, it is conceivable that it could be detectable (at least via imaging) during totality.





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