Comet Chasing in February

Comet chasing is the visual observation of telescopic comets.

News

  • 46P/Wirtanen passed perihelion in mid-December, when it also passed within 0.1 AU of the earth. It should continue to fade rapidly in February.

  • C/2018 Y1 (Iwamoto) will reach perihelion in early February. In the second week of February it will pass within 0.3 AU of the earth, when it is currently predicted to reach maximum brightness of magnitude 7.3.

  • C/2017 M4 (ATLAS) passed perhleion in mid January. It is predicted to reach maximum brightness of magnitude 13 in early May.

  • 78P/Gehrels will reach perihelion in early April, when it is currently predicted to reach maximum brightness of magnitude 11.5 in mid March.

  • C/2018 N2 (ASASSN) will reach perihelion in mid-November 2019. It is predicted to reach maximum brightness of magnitude 11 in late October 2019.

  • 123P/West-Hartley will reach perihelion in early February.

  • C/2018 N2 (ASASSN) will reach perihelion in mid November 2019. It is currently predicted to reach maximum brightness of magnitude 11.2 in late October.

  • 38P/Stephan-Oterma passed perihelion in early November. 

  • C/2018 L2 (ATLAS) passed perihelion in early December. It should fade slowly.

  • C/2018 V1 (Machholz-Fujikawa-Iwamoto) is a new rare visual discovery.  See MPEC 2018-V151 for the discovery details.  It passed perihelion in early December. It faded rapidly in January and no magnitude observations have been reported since late December.

  • 64P/Swift-Gehrels passed perihelion in early November, when it passed within 0.4 AU of the earth.

  • 21P/Giacobini-Zinner passed perihelion in early September. Also in early September this comet passed within 0.4 AU of the earth.

  • 29P/Schwassmann-Wachmann This comet has outbursts, resulting in a brightening of 0.5 - 1.0 magnitudes, which occur roughly every 59 days, typically taking 5-10 days to subside. But up to three subsequent outbursts may occur 5-10 days afterward, each typically smaller than the last, although on some occasions they can be even brighter than the first. These outbursts make 29P one of the most interesting comets to follow, both visually and scientifically. 29P/Schwassmann-Wachmann has a 14.8-year orbital period, and will next reach perihelion in early March 2019. But it varies in its distance from the Sun from 5.8 AU (at perihelion) to 6.3 AU (at aphelion), which is an unusually small variation for a comet, and remains quite far from the sun at all times. 

  • C/2016 M1 (PANSTARRS) passed perihelion in early August. Maximum brightness of magnitude 8 occurred in late July. 

  • C/2016 R2 (PANSTARRS) passed perihelion in early May. 

  • C/2015 O1 (PANSTARRS) is past perihelion, which occurred in mid February 2018. This comet has recently taken on an elongated appearance in images.

  • 240P/NEAT passed perihelion in May 2018. 

  • C/2017 S3 (PANSTARRS) has apparently disintegrated during perihelion passage.

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. But always remember, comets are like cats. They both have tails and do what they want, and not always what we expect. This is one of the things that makes comet chasing interesting!

Comet Synopses for February

Explanation of Comet Synopses and charts (read this if you have questions)

46P/Wirtanen: A morning comet visible in binoculars
This comet begins the month in Ursa Major at magnitude 6.7. Look for a 29.5' coma. It should fade rapidly.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N High at ~00:40 High at ~00:20 High in moonlight at ~23:30 High at ~22:50 High at ~23:00 1-
40o N High at ~00:40 High at ~00:20 Fairly high at ~05:10 High at ~22:30 High at ~23:00 1-
Equator Fairly high at ~00:40 Fairly high at ~00:10 Low in the northern sky at ~03:50 Fairly high at ~22:00 High at ~23:00 1-
30o S Very low in the northern sky at ~00:40 Very low in the northern sky at ~00:10 Low in the northern sky in moonlight at ~23:50 Very low in the northern sky at ~21:40 Low in the northern sky at ~23:00 1-

C/2018 Y1 (Iwamoto): A morning comet visible in binoculars
This comet begins the month in Virgo at magnitude 8.5. Look for a 7.5' coma. It should fade by about 0.6 magnitudes, moving into Auriga by month's end.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N Fairly high in the southern sky at ~03:50 High at ~01:40 High in moonlight at ~21:50 High at ~20:00 High at ~19:50 1-
40o N Fairly high at ~03:50 High at ~01:40 Very low in the western sky at ~05:10 High at ~19:50 High at ~19:40 1-
Equator High at ~03:50 High at ~01:40 High in moonlight at ~22:00 High at ~19:50 High at ~19:30 1-
30o S High at ~03:40 High at ~01:40 Fairly high in the northern sky in moonlight at ~22:10 Fairly high in the northern sky at ~20:10 Fairly high in the northern sky at ~20:00 1-

64P/Swift-Gehrels: An evening comet visible in small telescopes
This comet begins the month in Taurus at magnitude 10.3. Look for a 4.5' coma. It should fade rapidly.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N High at ~19:30 High at ~21:50 High during evening twilight at ~19:10 High at ~19:40 High at ~19:50 1-
40o N High at ~19:30 High in moonlight at ~19:20 High during evening twilight at ~19:10 High at ~19:30 High at ~19:30 1-
Equator High at ~19:40 High in moonlight at ~19:40 High during evening twilight at ~19:20 High at ~19:40 High at ~19:30 1-
30o S Fairly high at ~20:30 Fairly high in moonlight at ~20:20 Fairly high during evening twilight at ~20:00 Fairly high at ~20:10 Fairly high at ~20:00 1-

C/2018 L2 (ATLAS): A far-northern morning comet visible in a 6-inch (15 cm) telescope
This comet begins the month in Cygnus at magnitude 9.4. Look for a 6' coma. It should fade by about 0.5 magnitudes, moving into Lacerta by month's end.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N Fairly high in the eastern sky at ~05:40 Fairly high in the eastern sky at ~05:30 Fairly high in the eastern sky during morning twilight at ~05:40 Low in the western sky during evening twilight at ~19:20 Fairly high in the eastern sky at ~04:40 1-
40o N Low in the eastern sky during morning twilight at ~05:40 Low in the eastern sky during morning twilight at ~05:30 Low in the eastern sky during morning twilight at ~05:20 Very low in the western sky during evening twilight at ~19:00 Low in the eastern sky at ~05:00 1-
Equator Not visible Not visible Not visible Not visible Not visible  
30o S Not visible Not visible Not visible Not visible Not visible  

C/2016 M1 (PANSTARRS): A southern hemisphere evening comet visible in a 6-inch (15 cm) telescope
This comet begins the month in Hydrus at magnitude 11.1. Look for a 4' coma. It should fade slowly, moving into Reticulum by month's end. The best visibility is early in the month as seen from the southern hemisphere.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N Not visible Not visible Not visible Not visible Not visible  
40o N Not visible Not visible Not visible Not visible Not visible  
Equator Low in the southern sky at ~19:30 Low in the southern sky in moonlight at ~19:30 Low in the southern sky during evening twilight at ~19:20 Fairly high in the southern sky at ~19:30 Fairly high in the southern sky at ~19:30 1-
30o S High at ~20:40 Fairly high at ~21:40 Low in the southern sky at ~03:00 High at ~20:10 High at ~20:00 1-

38P/Stephan-Oterma: An evening comet visible in an 8-inch (20 cm) telescope
This comet begins the month in Lynx at magnitude 10.9. Look for a 4.5' coma. It should fade rapidly.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N High at ~23:40 High at ~23:10 High in moonlight at ~22:20 High at ~22:20 High at ~21:50 1-
40o N High at ~23:40 High at ~23:10 Fairly high in the western sky at ~05:10 High at ~22:20 High at ~21:50 1-
Equator High at ~23:40 High at ~23:10 Very low in the northern sky at ~03:50 High at ~22:00 High at ~21:50 1-
30o S Low in the northern sky at ~23:40 Low in the northern sky at ~23:10 Low in the northern sky in moonlight at ~22:40 Low in the northern sky at ~21:40 Low in the northern sky at ~21:50 1-

123P/West-Hartley: A morning comet visible in an 8-inch (20 cm) telescope
This comet begins the month in Ursa Major at magnitude 12.5. Look for a 1.5' coma. It should remain constant.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N High at ~02:50 High at ~02:20 High in moonlight at ~01:20 High at ~22:50 High at ~00:40 1-
40o N High at ~02:50 High at ~02:20 High at ~05:10 High at ~22:30 High at ~00:40 1-
Equator High at ~02:50 High at ~02:20 High at ~03:50 Fairly high at ~22:00 High at ~00:40 1-
30o S Fairly high in the northern sky at ~02:50 Fairly high in the northern sky at ~02:20 Fairly high in the northern sky at ~03:00 Fairly high in the northern sky in moonlight at ~01:30 Fairly high in the northern sky at ~00:40 1-

C/2015 O1 (PANSTARRS): A morning comet visible in a 14-inch (36 cm) telescope
This comet begins the month in Ursa Major at magnitude 13.5. Look for a 1' coma. It should fade slowly.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N High at ~01:50 High at ~01:10 High in moonlight at ~00:10 High at ~22:50 High at ~23:10 1-
40o N High at ~01:50 High at ~01:10 Fairly high at ~05:10 High at ~22:30 High at ~23:10 1-
Equator High at ~01:50 High at ~01:10 Fairly high in the northern sky at ~03:50 Fairly high at ~22:00 High at ~23:10 1-
30o S Low in the northern sky at ~01:50 Low in the northern sky at ~01:10 Very low in the northern sky at ~02:50 Low in the northern sky at ~21:40 Low in the northern sky at ~23:10 1-

C/2016 N6 (PANSTARRS): An evening comet visible in a 14-inch (36 cm) telescope
This comet begins the month in Canis Major at magnitude 13.7. Look for a 40" coma. It should fade by about 0.6 magnitudes, moving into Lepus by month's end. The best visibility is early in the month as seen from the southern hemisphere.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N Low in the southern sky at ~21:20 Low in the southern sky at ~20:40 Low in the southern sky in moonlight at ~20:10 Low in the southern sky at ~19:40 Low in the southern sky during evening twilight at ~19:30 1-
40o N Fairly high in the southern sky at ~21:20 Fairly high in the southern sky at ~21:50 Fairly high in the southern sky in moonlight at ~20:00 Fairly high in the southern sky at ~19:40 Fairly high in the southern sky at ~19:30 1-
Equator High at ~21:20 High at ~21:50 High in moonlight at ~20:00 High at ~19:40 High at ~19:40 1-
30o S High at ~21:20 High at ~21:40 High in moonlight at ~20:10 High at ~20:10 High at ~20:00 1-

78P/Gehrels: An evening comet visible in a 16-inch (41 cm) telescope
This comet begins the month in Pisces at magnitude 11.6. Look for a 3' coma. It should remain constant.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N Fairly high in the western sky during evening twilight at ~18:40 Low in the western sky during evening twilight at ~18:50 Low in the western sky during evening twilight at ~18:50 Low in the western sky during evening twilight at ~19:20 Low in the western sky during evening twilight at ~19:30 1-
40o N Fairly high in the western sky at ~18:50 Fairly high in the western sky during evening twilight at ~19:00 Fairly high in the western sky during evening twilight at ~18:50 Low in the western sky during evening twilight at ~19:10 Low in the western sky during evening twilight at ~19:20 1-
Equator Fairly high in the western sky during evening twilight at ~19:30 Fairly high in the western sky during evening twilight at ~19:30 Fairly high in the western sky during evening twilight at ~19:10 Low in the western sky during evening twilight at ~19:20 Low in the western sky during evening twilight at ~19:20 1-
30o S Low in the western sky during evening twilight at ~20:10 Very low in the western sky during evening twilight at ~20:00 Very low in the western sky during evening twilight at ~19:50 Very low in the western sky during evening twilight at ~19:40 Very low in the western sky during evening twilight at ~19:30 1-

C/2017 M4 (ATLAS): A morning comet visible in an 18-inch (46 cm) telescope
This comet begins the month in Serpens Cauda at magnitude 13.9. Look for a 40" coma. It should brighten slowly, moving into Ophiuchus by month's end.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N Low in the southern sky during morning twilight at ~05:50 Low in the southern sky during morning twilight at ~05:40 Low in the southern sky during morning twilight at ~05:50 Low in the southern sky during morning twilight at ~05:30 Very low in the southern sky during morning twilight at ~05:00 1-
40o N Low in the eastern sky during morning twilight at ~05:40 Fairly high in the southern sky during morning twilight at ~05:30 Fairly high in the southern sky at ~05:20 Fairly high in the southern sky during morning twilight at ~05:20 Fairly high in the southern sky at ~05:00 1-
Equator Fairly high at ~05:00 Fairly high at ~05:00 High at ~05:00 High during morning twilight at ~05:10 High in moonlight at ~04:50 1-
30o S Fairly high in the eastern sky during morning twilight at ~04:00 Fairly high at ~04:10 High at ~04:10 High during morning twilight at ~04:30 High in moonlight at ~04:20 1-

29P/Schwassmann-Wachmann: An evening comet visible in very large telescopes
This comet begins the month in Pisces at magnitude 10.0, apparently in outburst at the end of january. Look for a 7' coma. It should fade as the outburst passes.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N Low in the western sky during evening twilight at ~18:40 Low in the western sky during evening twilight at ~18:50 Low in the western sky during evening twilight at ~18:40 Very low in the western sky during evening twilight at ~19:00 Not visible 1-
40o N Low in the western sky during evening twilight at ~18:50 Low in the western sky during evening twilight at ~19:00 Low in the western sky during evening twilight at ~18:50 Very low in the western sky during evening twilight at ~19:00 Not visible 1-27
Equator Low in the western sky during evening twilight at ~19:30 Low in the western sky during evening twilight at ~19:20 Very low in the western sky during evening twilight at ~19:10 Very low in the western sky during evening twilight at ~19:00 Not visible 1-21, 23-23
30o S Very low in the western sky during evening twilight at ~20:00 Not visible Not visible Not visible Not visible 1-6

C/2018 N2 (ASASSN): An evening comet visible in very large telescopes
This comet begins the month in Sculptor at magnitude 14.0. Look for a 1' coma. It should brighten slowly, moving into Cetus by month's end.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N Very low in the southern sky during evening twilight at ~18:20 Very low in the southern sky during evening twilight at ~18:30 Not visible Not visible Not visible 1-14
40o N Low in the southern sky during evening twilight at ~18:50 Low in the southern sky during evening twilight at ~18:50 Low in the western sky during evening twilight at ~18:50 Very low in the western sky during evening twilight at ~19:00 Very low in the western sky during evening twilight at ~19:00 1-
Equator Fairly high at ~19:30 Fairly high in moonlight at ~19:30 Fairly high in the western sky during evening twilight at ~19:20 Fairly high in the western sky during evening twilight at ~19:30 Low in the western sky during evening twilight at ~19:20 1-
30o S Fairly high at ~20:30 Fairly high during evening twilight at ~20:20 Fairly high in the western sky during evening twilight at ~20:00 Fairly high in the western sky during evening twilight at ~20:00 Low in the western sky during evening twilight at ~19:50 1-

60P/Tsuchinshan: A morning comet visible in very large telescopes
This comet begins the month in Virgo at magnitude 14.0. Look for a 1' coma. It should fade slowly.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N Fairly high in the southern sky at ~03:00 Fairly high in the southern sky at ~02:30 Fairly high in the southern sky in moonlight at ~01:40 Fairly high in the southern sky at ~22:50 Fairly high in the southern sky at ~01:00 1-
40o N High at ~03:00 High at ~02:30 Fairly high in the western sky at ~05:10 Fairly high in the eastern sky at ~22:30 High at ~01:00 1-
Equator High at ~03:00 High at ~02:30 High at ~03:50 Fairly high at ~22:00 High at ~01:00 1-
30o S High at ~03:00 High at ~02:30 High at ~03:00 Fairly high at ~21:40 High at ~01:00 1-

C/2016 R2 (PANSTARRS): A morning comet visible in very large telescopes
This comet begins the month in Hercules at magnitude 14.1. Look for a 1' coma. It should fade slowly.  FINDER CHART
Latitude Visibility February 2 Visibility February 9 Visibility February 16 Visibility February 23 Visibility March 2 Nights Visible
55o N High at ~05:30 High at ~05:20 High in moonlight at ~04:00 Fairly high in the eastern sky at ~22:50 High at ~04:30 1-
40o N High at ~05:20 High at ~05:20 High at ~05:10 High during morning twilight at ~05:10 High at ~04:50 1-
Equator Fairly high at ~05:00 High at ~05:00 High at ~04:50 High during morning twilight at ~05:00 High in moonlight at ~04:50 1-
30o S Very low in the northern sky during morning twilight at ~04:20 Low in the northern sky during morning twilight at ~04:20 Low in the northern sky during morning twilight at ~04:20 Low in the northern sky during morning twilight at ~04:40 Low in the northern sky during morning twilight at ~04:30 1-

Summary Data for This Month's Telescopic Comets

Comets brighter than 15th magnitude.  This table is updated as necessary.  The last column indicates the date of the last observation used to compute these values.  The constellation listed is where the comet was on the first of the month.

Comet Constellation

February 1st

February 15th

February 28th

 Observations as of (UT)
Mag Diam Mag Diam Mag Diam
C/2018 Y1 (Iwamoto) Virgo 6.2 24.3' 5.0 42.2' 6.7 20.2' 2019 January 22
46P/Wirtanen Ursa Major 6.7 30.3' 7.9 22.4' 8.9 17.4' 2019 January 26
C/2018 L2 (ATLAS) Cygnus 9.4 5.9' 9.7 5.7' 9.9 5.5' 2019 January 26
29P/Schwassmann-Wachmann Pisces 10.0 6.9' 10.1 6.8' 10.1 6.7' 2019 January 26
64P/Swift-Gehrels Taurus 10.3 4.7' 11.3 3.9' 12.3 3.4' 2019 January 26
38P/Stephan-Oterma Lynx 10.9 4.8' 11.8 4.2' 12.7 3.6' 2019 January 26
C/2016 M1 (PANSTARRS) Hydrus 11.1 4.0' 11.3 3.9' 11.5 3.8' 2019 January 15
78P/Gehrels Pisces 11.6 2.8' 11.6 2.8' 11.6 2.7' 2019 January 7
123P/West-Hartley Ursa Major 12.5 1.4' 12.4 1.5' 12.4 1.5' 2019 January 22
C/2015 O1 (PANSTARRS) Ursa Major 13.5 1.1' 13.5 1.1' 13.7 1.0' 2018 December 12
C/2016 N6 (PANSTARRS) Canis Major 13.7 40" 14.0 37" 14.3 34" 2019 January 15
C/2017 M4 (ATLAS) Serpens Cauda 13.9 39" 13.8 42" 13.7 44" 2019 January 19
C/2018 N2 (ASASSN) Sculptor 14.0 1.0' 13.9 1.0' 13.9 1.0' 2019 January 22
60P/Tsuchinshan Virgo 14.0 1.1' 14.1 1.1' 14.3 1.1' 2019 January 27
C/2016 R2 (PANSTARRS) Hercules 14.1 1.0' 14.2 1.0' 14.3 1.0' 2019 January 24
21P/Giacobini-Zinner Columba 14.6 56" 15.2 50" 15.8 44" 2019 January 20
C/2018 A3 (ATLAS) Camelopardalis 14.7 35" 14.8 33" 15.0 31" 2019 January 21
C/2017 T2 (PANSTARRS) Eridanus 15.5 23" 15.4 22" 15.4 22" 2019 January 26
240P/NEAT Ursa Major 15.6 31" 15.7 31" 15.8 30" 2019 January 22
*In solar conjunction and generally not visible

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

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
Weekly Information About Bright Comets
Cometography