Comet Chasing in January

News

• 2011 W3 (Lovejoy) has unexpectedly survived perihelion! This comet is visible just before dawn from the southern hemisphere.

• P/2006 T1 (Levy) is very faint--possibly fainter than 20th magnitude. Various web sites and most software (online or otherwise--including Google Sky) is showing this comet as 11th magnitude. There are web sites predicting it will be 7th magnitude in January, which is highly doubtful. In fact this comet  has not been observed since 2006 and the orbital data and magnitude parameters are not up to date. The creators of these web sites and software do not monitor actual observations and the result is unreliable information. In fact these sources also still show 2010 X1 (Elenin) which disintegrated over a month ago! What a huge disservice they are doing. I urge readers to complain about it to them.

• 2010 X1 (Elenin) has disintegrated. It faded dramatically after a solar flare on August 20. Images at the end of August revealed a spreading, more diffuse coma. The remnants of this comet can be observed visually, but it is a difficult observation requiring a dark site and considerable expertise in spotting diffuse objects.

• 2011 Q4 (SWAN) is a new discovery of September 5 via SWAN, apparently independently by Vladimir Bezugly and Rob Matson. See below for details.

Comet Visibility in the Eyepiece

This page uses code developed for SkyTools 3 to predict the visibility of a comet in the eyepiece.  Predicting how much aperture is required to see a comet is a very complex task.  Have a look for yourself: a comparison of the predictions below (such as "visible in small telescopes") to the magnitude of each comet shows just how poor an indicator the magnitude alone really is.  When you read below that a particular aperture is required to see a comet you can have a reasonable degree of confidence that the comet can in fact be seen in the eyepiece.

Make your own custom charts and predictions for your location and equipment: software for comet observing

Comet Synopses for January

C/2011 W3 (Lovejoy): A morning comet visible in binoculars
This comet begins the month in Ara with a coma magnitude of 5. Look for at least a 5^o tail, which is this comet's most visible feature. It should fade rapidly, moving into Caelum by month's end. The best visibility is early in the month as seen from the southern hemisphere.  FINDER CHART

Latitude	Visibility December 31	Visibility January 7	Visibility January 14	Visibility January 21	Visibility January 28	Nights Visible
55o N	Not visible	Not visible	Not visible	Not visible	Not visible
40o N	Not visible	Not visible	Not visible	Not visible	Very low in the southern sky in moonlight at ~20:10	24-
Equator	Very low in the southern sky during morning twilight at ~05:00	Not visible	Low in the southern sky at ~21:00	Fairly high at ~20:40	High in moonlight at ~20:00	1-5, 9-
30o S	Fairly high in the southern sky during morning twilight at ~03:30	Fairly high in the southern sky in moonlight at ~01:20	High at ~21:00	High at ~20:50	High at ~21:50	1-

C/2009 P1 (Garradd): A morning comet visible in binoculars
This comet begins the month in Hercules at magnitude 6.7. Look for a 5" coma. It should brighten slowly.  FINDER CHART

Latitude	Visibility December 31	Visibility January 7	Visibility January 14	Visibility January 21	Visibility January 28	Nights Visible
55o N	Fairly high during morning twilight at ~06:10	High during morning twilight at ~06:30	High during morning twilight at ~06:10	High at ~06:00	High at ~05:50	1-
40o N	Fairly high in the eastern sky during morning twilight at ~05:50	Fairly high during morning twilight at ~06:00	High during morning twilight at ~05:50	High at ~05:40	High at ~05:40	1-
Equator	Not visible	Low in the eastern sky during morning twilight at ~05:10	Low in the eastern sky during morning twilight at ~05:10	Fairly high in the eastern sky during morning twilight at ~05:00	Fairly high in the eastern sky during morning twilight at ~05:00	1-
30o S	Not visible	Not visible	Not visible	Not visible	Not visible	1-20, 25-

29P/Schwassmann-Wachmann: A morning comet visible in a 12.5-inch telescope
This comet begins the month in Corvus, perhaps as bright as magnitude 10.2. Look for a 7' coma. This comet was apparently caught in one of its frequent outbursts near the end of December. It is typically much fainter.  FINDER CHART

Latitude	Visibility December 31	Visibility January 7	Visibility January 14	Visibility January 21	Visibility January 28	Nights Visible
55o N	Fairly high in the southern sky at ~05:50	Fairly high in the southern sky in moonlight at ~05:10	Fairly high in the southern sky in moonlight at ~04:50	Fairly high in the southern sky at ~04:40	Fairly high in the southern sky at ~04:10	1-
40o N	Fairly high at ~05:40	Fairly high in moonlight at ~04:50	Fairly high in moonlight at ~04:40	Fairly high at ~04:40	Fairly high at ~04:10	1-
Equator	High at ~04:40	High during morning twilight at ~05:10	High in moonlight at ~04:40	High at ~04:30	High at ~04:10	1-
30o S	High during morning twilight at ~03:30	High during morning twilight at ~03:40	High during morning twilight at ~03:50	High at ~03:40	High at ~03:50	1-

78P/Gehrels: An evening comet visible in a 12.5-inch telescope
This comet begins the month in Pisces at magnitude 10.6. Look for a 4.5' coma. It should fade slowly.  FINDER CHART

Latitude	Visibility December 31	Visibility January 7	Visibility January 14	Visibility January 21	Visibility January 28	Nights Visible
55o N	Fairly high during evening twilight at ~18:00	Fairly high in moonlight at ~18:10	Fairly high at ~18:20	Fairly high at ~18:30	Fairly high during evening twilight at ~18:30	1-
40o N	High during evening twilight at ~18:20	High during evening twilight at ~18:20	High at ~18:40	High at ~18:40	High during evening twilight at ~18:50	1-
Equator	High during evening twilight at ~19:20	High during evening twilight at ~19:20	High at ~19:30	High at ~19:30	High during evening twilight at ~19:30	1-
30o S	High during evening twilight at ~20:30	Fairly high during evening twilight at ~20:20	Fairly high during evening twilight at ~20:30	Fairly high during evening twilight at ~20:30	Fairly high in the western sky during evening twilight at ~20:20	1-

C/2010 S1 (LINEAR): A northern hemisphere evening comet visible in a 12.5-inch telescope
This comet begins the month in Lacerta at magnitude 13.6. Look for a 30" coma. It should remain constant, moving into Andromeda by month's end.  FINDER CHART

Latitude	Visibility December 31	Visibility January 7	Visibility January 14	Visibility January 21	Visibility January 28	Nights Visible
55o N	High in moonlight at ~18:00	High during evening twilight at ~18:00	High at ~18:20	High at ~18:30	High during evening twilight at ~18:30	1-
40o N	High during evening twilight at ~18:20	High during evening twilight at ~18:20	High at ~18:30	High at ~18:40	High during evening twilight at ~18:40	1-
Equator	Fairly high in the northern sky during evening twilight at ~19:10	Fairly high in the northern sky during evening twilight at ~19:10	Low in the northern sky during evening twilight at ~19:20	Low in the northern sky during evening twilight at ~19:20	Low in the northern sky during evening twilight at ~19:10	1-
30o S	Not visible	Not visible	Not visible	Not visible	Not visible

C/2010 G2 (Hill): An evening comet visible in a 14-inch telescope
This comet begins the month in Cetus at magnitude 10.3. Look for a 4.5' coma. It should fade by about 1.1 magnitudes, moving into Eridanus by month's end.  FINDER CHART

Latitude	Visibility December 31	Visibility January 7	Visibility January 14	Visibility January 21	Visibility January 28	Nights Visible
55o N	Fairly high in moonlight at ~20:20	Fairly high in moonlight at ~19:50	Fairly high at ~19:20	Fairly high at ~18:50	Fairly high in moonlight at ~18:40	1-
40o N	High in moonlight at ~20:20	High in moonlight at ~19:50	High at ~19:20	High at ~19:00	High in moonlight at ~18:50	1-
Equator	High at ~23:40	High in moonlight at ~19:50	High at ~19:40	High at ~19:30	High in moonlight at ~19:30	1-
30o S	Fairly high at ~23:20	High during evening twilight at ~20:30	High at ~20:40	High during evening twilight at ~20:30	High during evening twilight at ~20:30	1-

21P/Giacobini-Zinner: A northern hemisphere evening comet visible in very large telescopes
This comet begins the month in Aquila at magnitude 8.9. Look for a 10' coma. It should brighten by about 0.9 magnitudes, moving into Aquarius by month's end.  FINDER CHART

Latitude	Visibility December 31	Visibility January 7	Visibility January 14	Visibility January 21	Visibility January 28	Nights Visible
55o N	Low in the western sky during evening twilight at ~17:40	Low in the western sky during evening twilight at ~17:30	Very low in the western sky during evening twilight at ~17:50	Very low in the western sky during evening twilight at ~18:00	Very low in the western sky during evening twilight at ~18:10	1-
40o N	Low in the western sky during evening twilight at ~18:10	Low in the western sky during evening twilight at ~18:00	Low in the western sky during evening twilight at ~18:20	Very low in the western sky during evening twilight at ~18:30	Very low in the western sky during evening twilight at ~18:30	1-
Equator	Very low in the western sky during evening twilight at ~19:00	Very low in the western sky during evening twilight at ~19:00	Very low in the western sky during evening twilight at ~19:10	Very low in the western sky during evening twilight at ~19:10	Very low in the western sky during evening twilight at ~19:10	1-
30o S	Not visible	Not visible	Not visible	Not visible	Not visible

C/2011 Q4 (SWAN): A morning comet visible in very large telescopes
This comet begins the month in Bootes at magnitude 11.6. Look for a 3.5' coma. It should fade slowly, moving into Canes Venatici by month's end.  FINDER CHART

Latitude	Visibility December 31	Visibility January 7	Visibility January 14	Visibility January 21	Visibility January 28	Nights Visible
55o N	High at ~06:00	High in moonlight at ~05:50	High during morning twilight at ~06:10	High at ~05:40	High at ~05:10	1-
40o N	High at ~05:40	High at ~05:40	High during morning twilight at ~05:50	High at ~05:30	High at ~05:10	1-
Equator	High during morning twilight at ~04:50	High during morning twilight at ~05:10	High during morning twilight at ~05:00	High at ~04:50	High at ~04:50	1-
30o S	Low in the eastern sky during morning twilight at ~03:50	Fairly high in the northern sky during morning twilight at ~04:10	Fairly high in the northern sky during morning twilight at ~04:00	Fairly high in the northern sky during morning twilight at ~04:00	Low in the northern sky during morning twilight at ~04:00	1-

45P/Honda-Mrkos-Pajdusakova: A morning comet visible in very large telescopes
This comet begins the month in Virgo at magnitude 12.4. Look for a 3' coma. It should fade rapidly.  FINDER CHART

Latitude	Visibility December 31	Visibility January 7	Visibility January 14	Visibility January 21	Visibility January 28	Nights Visible
55o N	Fairly high in the southern sky during morning twilight at ~06:10	Fairly high in the southern sky during morning twilight at ~06:20	Fairly high in the southern sky during morning twilight at ~06:10	Fairly high in the southern sky at ~05:50	Fairly high in the southern sky at ~05:30	1-
40o N	Fairly high at ~05:40	Fairly high during morning twilight at ~05:50	High during morning twilight at ~05:50	High at ~05:40	High at ~05:30	1-
Equator	High at ~04:40	High during morning twilight at ~05:10	High during morning twilight at ~05:00	High at ~04:50	High at ~04:50	1-
30o S	Fairly high during morning twilight at ~03:30	High during morning twilight at ~03:50	High during morning twilight at ~03:50	High during morning twilight at ~03:50	High at ~03:50	1-

49P/Arend-Rigaux: A morning comet visible in very large telescopes
This comet begins the month in Virgo at magnitude 13.5. Look for a 1' coma. It should fade slowly, moving into Coma Berenices by month's end.  FINDER CHART

Latitude	Visibility December 31	Visibility January 7	Visibility January 14	Visibility January 21	Visibility January 28	Nights Visible
55o N	High at ~05:20	High in moonlight at ~04:20	High in moonlight at ~05:10	High at ~04:20	High at ~04:00	1-
40o N	High at ~05:20	High in moonlight at ~04:10	High in moonlight at ~05:10	High at ~04:20	High at ~04:00	1-
Equator	High at ~04:40	High during morning twilight at ~05:10	High in moonlight at ~04:50	High at ~04:20	High at ~04:00	1-
30o S	High during morning twilight at ~03:30	High during morning twilight at ~03:40	High during morning twilight at ~03:50	High at ~03:40	High at ~03:50	1-

Summary Data for This Month's Telescopic Comets

*In solar conjunction and not visible

For the latest news and comet observations see the ICQ/CBAT/MPC: Recent Comet Magnitude Estimates page.  The Astronomical Headlines page of the IAU is also a good source of information, particularly for recent discoveries.

For general information about comets see Gary W. Kronk's Cometography 

Join the Comet Chasing discussion group 

Further reading: see Comet Chasing, Sky & Telescope, April 2005, pg. 83.

Make your own custom charts for your location and telescope/binoculars: software for comet observing
 

Links Skyhound's Guide to Comets Skyhound's Guide to Finding Comets BAA Comet Section Astronomical Headlines (IAU) Cometography

Visit Software or the Skyhound observing page.