Comet Chasing in March


Comet chasing is the visual observation of telescopic comets.

News


  • 2P/Encke will reach perihelion in early March. Also in early March this comet will pass within 0.7 AU of the earth. It is currently predicted to reach maximum brightness of magnitude ~4 in early March. Be aware that it is large and diffuse, which will make it harder to spot than its magnitude alone would suggest.

  • 45P/Honda-Mrkos-Pajdusakova  passed perihelion in late December. In early February this comet passed within 0.1 AU of the earth. 

  • 73P/Schwassmann-Wachmann split in two on February 10. The new component is larger and substantially brighter, forming a comet pair. The pair will next perihelion in mid March when they will be at their brightest. More here.

  • 41P/Tuttle-Giacobini-Kresak will next reach perihelion in mid April. In early April this comet will pass within 0.1 AU of the earth. It is currently  predicted to reach maximum brightness of magnitude 5.5 in early April. 

  • C/2016 VZ187 (PANSTARRS) was discovered in November. It may have brightened in late February. It will reach perihelion in early March. In early April this comet will pass within 0.5 AU of the earth.

  • C/2015 ER61 (PANSTARRS) will reach perihelion in early May. It is predicted to reach maximum brightness of magnitude 8.8 in late April.

  • C/2015 V2 (Johnson) will reach perihelion in mid June 2017. It is currently predicted to reach maximum brightness of magnitude ~7 in early June.

  • 237P/LINEAR will passed perihelion in mid October. It reached maximum brightness of magnitude in late September.

  • 29P/Schwassmann-Wachmann had another large outburst near the beginning of November,  brightening to magnitude 12.8. It has now faded to ~15th magnitude. Outbursts occur roughly every 50 days. 

73P and fragment 73P-BT (lower right) on February 13. You can read an article about this image stack, and a movie made from the same set of images here

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.

Comet Synopses for March


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

41P/Tuttle-Giacobini-Kresak: A morning comet visible in binoculars
This comet begins the month in Leo at magnitude 8.9. Look for a 14.5' coma. It should brighten rapidly, moving into Draco by month's end.  FINDER CHART
Latitude Visibility March 4 Visibility March 11 Visibility March 18 Visibility March 25 Visibility April 1 Nights Visible
55o N High at ~01:20 High in moonlight at ~22:50 High at ~23:00 High at ~23:40 High at ~01:00 1-
40o N High at ~00:30 High in moonlight at ~22:50 High at ~23:00 High at ~23:40 High at ~01:00 1-
Equator High at ~23:40 High in moonlight at ~22:50 Fairly high at ~22:50 Fairly high at ~23:40 Fairly high in the northern sky at ~01:00 1-
30o S Fairly high in the northern sky at ~23:00 Low in the northern sky in moonlight at ~22:50 Very low in the northern sky at ~22:10 Not visible Not visible 1-24

2P/Encke: A morning comet visible in binoculars
This comet begins the month in Pisces at magnitude 5.5. Look for a 2.5' coma. It should fade rapidly, moving into Aquarius by month's end. The best visibility is late in the month as seen from the southern hemisphere.  FINDER CHART
Latitude Visibility March 4 Visibility March 11 Visibility March 18 Visibility March 25 Visibility April 1 Nights Visible
55o N Very low in the western sky during evening twilight at ~18:50 Not visible Not visible Not visible Not visible 1-7
40o N Very low in the western sky during evening twilight at ~18:50 Not visible Not visible Not visible Not visible 1-7
Equator Very low in the western sky during evening twilight at ~18:50 Not visible Very low in the eastern sky during morning twilight at ~05:30 Very low in the eastern sky during morning twilight at ~05:00 Low in the eastern sky during morning twilight at ~05:00 1-7, 15-
30o S Not visible Not visible Very low in the eastern sky during morning twilight at ~05:10 Low in the eastern sky during morning twilight at ~04:50 Fairly high in the eastern sky during morning twilight at ~04:50 1-3, 14-

C/2015 ER61 (PANSTARRS): A morning comet visible in small telescopes
This comet begins the month in Sagittarius at magnitude 9.8. Look for a 5.5' coma. It should brighten by about 1.0 magnitudes, moving into Capricornus by month's end. The best visibility is late in the month as seen from the southern hemisphere.  FINDER CHART
Latitude Visibility March 4 Visibility March 11 Visibility March 18 Visibility March 25 Visibility April 1 Nights Visible
55o N Very low in the southern sky during morning twilight at ~05:10 Very low in the southern sky during morning twilight at ~05:10 Very low in the southern sky during morning twilight at ~04:50 Very low in the eastern sky during morning twilight at ~04:20 Very low in the eastern sky during morning twilight at ~04:10 1-
40o N Low in the southern sky during morning twilight at ~05:00 Low in the southern sky during morning twilight at ~05:10 Low in the southern sky during morning twilight at ~04:50 Low in the eastern sky during morning twilight at ~04:30 Low in the eastern sky during morning twilight at ~04:20 1-
Equator High at ~05:00 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 High at ~04:30 High during morning twilight at ~04:50 High during morning twilight at ~04:50 High at ~04:40 High at ~04:50 1-

C/2015 V2 (Johnson): A morning comet visible in small telescopes
This comet begins the month in Hercules at magnitude 10.6. Look for a 2.5' coma. It should brighten by about 1.0 magnitudes by month's end.  FINDER CHART
Latitude Visibility March 4 Visibility March 11 Visibility March 18 Visibility March 25 Visibility April 1 Nights Visible
55o N High at ~04:20 High in moonlight at ~03:40 High at ~00:40 High at ~03:20 High at ~03:00 1-
40o N High at ~04:40 High in moonlight at ~03:50 Fairly high at ~23:50 High at ~04:00 High at ~03:40 1-
Equator High at ~04:50 High in moonlight at ~04:20 High in moonlight at ~04:50 High at ~04:20 High at ~03:50 1-
30o S Low in the northern sky during morning twilight at ~04:40 Low in the northern sky during morning twilight at ~04:50 Low in the northern sky in moonlight at ~04:40 Low in the northern sky at ~04:10 Low in the northern sky at ~03:50 1-

73P/Schwassmann-Wachmann: A morning comet visible in small telescopes
This comet split last month and is now a pair of comets. The new, brighter and larger, coma has been designated as 73P-BT. It is the easier of the two to spot. They begin the month in Ophiuchus at magnitude 10.1/12.2. Look for 2'/40" comas. The fainter component is visible in 8-inch or larger telescopes. Both components should brighten only slightly, moving into Sagittarius by month's end. The best visibility is late in the month as seen from the southern hemisphere.  FINDER CHART
Latitude Visibility March 4 Visibility March 11 Visibility March 18 Visibility March 25 Visibility April 1 Nights Visible
55o N Not visible Not visible Not visible Not visible Not visible  
40o N Very low in the eastern sky during morning twilight at ~05:10 Very low in the eastern sky during morning twilight at ~05:20 Very low in the eastern sky during morning twilight at ~05:10 Not visible Not visible 1-
Equator Fairly high in the eastern sky at ~05:00 Fairly high in the eastern sky during morning twilight at ~05:10 Fairly high in the eastern sky during morning twilight at ~05:10 Low in the eastern sky during morning twilight at ~05:00 Low in the eastern sky during morning twilight at ~04:50 1-
30o S Fairly high in the eastern sky at ~04:30 Fairly high in the eastern sky during morning twilight at ~05:00 Fairly high in the eastern sky during morning twilight at ~04:50 Fairly high in the eastern sky during morning twilight at ~04:50 Fairly high in the eastern sky during morning twilight at ~04:50 1-

237P/LINEAR: A morning comet visible in an 8-inch (20 cm) telescope
This comet begins the month in Aquarius at magnitude 10.4. Look for a 2.5' coma. It should fade slowly, moving into Pegasus by month's end.  FINDER CHART
Latitude Visibility March 4 Visibility March 11 Visibility March 18 Visibility March 25 Visibility April 1 Nights Visible
55o N Not visible Not visible Not visible Not visible Very low in the eastern sky during morning twilight at ~04:20 2-3, 5-
40o N Not visible Very low in the eastern sky during morning twilight at ~05:20 Very low in the eastern sky during morning twilight at ~05:10 Very low in the eastern sky during morning twilight at ~04:50 Very low in the eastern sky during morning twilight at ~04:30 1-
Equator Not visible Very low in the eastern sky during morning twilight at ~05:20 Very low in the eastern sky during morning twilight at ~05:10 Very low in the eastern sky during morning twilight at ~05:00 Low in the eastern sky during morning twilight at ~05:00 1-
30o S Not visible Not visible Very low in the eastern sky during morning twilight at ~05:10 Very low in the eastern sky during morning twilight at ~05:00 Very low in the eastern sky during morning twilight at ~05:00 7-

315P/LONEOS: A morning comet visible in a 12.5-inch (32 cm) telescope
This comet begins the month in Ursa Major at magnitude 13.7. Look for a 25" coma. It should fade slowly.  FINDER CHART
Latitude Visibility March 4 Visibility March 11 Visibility March 18 Visibility March 25 Visibility April 1 Nights Visible
55o N High at ~01:20 High in moonlight at ~00:40 High at ~00:00 High at ~23:30 High at ~00:20 1-
40o N High at ~01:00 High in moonlight at ~00:40 High at ~23:50 High at ~23:30 High at ~23:30 1-
Equator High at ~01:00 High in moonlight at ~00:40 High at ~22:50 High at ~23:30 High at ~23:00 1-
30o S Fairly high in the northern sky at ~01:00 Fairly high in the northern sky in moonlight at ~00:30 Fairly high in the northern sky at ~22:10 Fairly high in the northern sky at ~23:30 Fairly high in the northern sky at ~23:00 1-

45P/Honda-Mrkos-Pajdusakova: A morning comet visible in an 18-inch (46 cm) telescope
This comet begins the month in Leo at magnitude 9.6. Look for a 18' coma. It should fade rapidly.  FINDER CHART
Latitude Visibility March 4 Visibility March 11 Visibility March 18 Visibility March 25 Visibility April 1 Nights Visible
55o N High at ~01:20 High in moonlight at ~23:30 High at ~22:50 High at ~22:20 High at ~00:20 1-
40o N High at ~00:30 High in moonlight at ~23:30 High at ~22:50 High at ~22:20 High at ~23:30 1-
Equator High at ~00:10 High in moonlight at ~23:30 High at ~22:50 High at ~22:20 High at ~22:30 1-
30o S Fairly high at ~00:10 Fairly high in moonlight at ~23:30 Fairly high at ~22:10 Fairly high at ~22:20 High at ~21:50 1-

C/2016 VZ18 (PANSTARRS): An evening comet visible in very large telescopes
This comet begins the month in Triangulum at magnitude 12.7. Look for a 2' coma. Experienced observers at a dark site may be able to detect this comet in much smaller apertures, given that is is very diffuse. It should remain constant, moving into Camelopardus by month's end.  FINDER CHART
Latitude Visibility March 4 Visibility March 11 Visibility March 18 Visibility March 25 Visibility April 1 Nights Visible
55o N High during evening twilight at ~19:40 High during evening twilight at ~19:40 High at ~20:20 High at ~20:40 High at ~00:20 1-
40o N High during evening twilight at ~19:20 High during evening twilight at ~19:20 High at ~19:50 High at ~20:00 Fairly high at ~23:30 1-
Equator Fairly high in the western sky during evening twilight at ~19:20 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 Very low in the northern sky during evening twilight at ~19:30 Not visible Not visible Not visible Not visible 1-5

C/2014 S2 (PANSTARRS): A morning comet visible in very large telescopes
This comet begins the month in Corvus at magnitude 13.2. Look for a 3.5' coma. It should fade slowly. The best visibility is early in the month as seen from the southern hemisphere.  FINDER CHART
Latitude Visibility March 4 Visibility March 11 Visibility March 18 Visibility March 25 Visibility April 1 Nights Visible
55o N Low in the southern sky at ~02:00 Low in the southern sky in moonlight at ~01:30 Low in the southern sky at ~00:40 Low in the southern sky at ~00:20 Low in the southern sky at ~00:20 1-
40o N Fairly high at ~02:00 Fairly high in moonlight at ~01:30 Fairly high at ~23:50 Fairly high at ~00:20 Fairly high at ~23:50 1-
Equator High at ~02:00 High in moonlight at ~01:30 High at ~22:50 High at ~00:20 High at ~23:50 1-
30o S High at ~02:00 High in moonlight at ~01:30 High at ~22:10 High at ~00:20 High at ~23:50 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

March 1st

March 15th

March 31st

Observations as of (UT)
Mag Diam Mag Diam Mag Diam
2P/Encke Pisces 5.2 2.8' 4.2 3.3' 8.4 2.5' 2017 February 15
41P/Tuttle-Giacobini-Kresak Leo 8.8 9.6' 7.2 12.5' 5.9 14.5' 2017 February 27
C/2015 ER61 (PANSTARRS) Sagittarius 9.7 4.3' 9.3 4.9' 8.8 5.4' 2017 February 23
45P/Honda-Mrkos-Pajdusakova Leo 9.8 18.0' 12.1 10.5' 14.3 6.6' 2017 February 28
237P/LINEAR Aquarius 10.4 2.6' 10.5 2.6' 10.5 2.6' 2016 November 17
C/2015 V2 (Johnson) Hercules 10.5 2.0' 10.1 2.3' 9.6 2.6' 2017 March 3
73P-BT/Schwassmann-Wachmann Sagittarius 10.1 2' 10.1 1.9' 10.3 11.8' 2017 February 22
73P/Schwassmann-Wachmann Sagittarius 12.2 40" 12.1 37" 12.4 45" 2017 January 28
C/2016 VZ18 (PANSTARRS) Triangulum 12.7 2.0' 12.5 2.2' 12.7 2.4' 2017 March 2
C/2016 U1 (NEOWISE) Sculptor 13.4 1.7' 14.5 1.5' 15.5 1.4' 2016 December 29
315P/LONEOS Ursa Major 13.7 23" 13.8 22" 14.0 21" 2017 January 24
C/2016 R2 (PANSTARRS) Fornax 14.2 3.5' 14.1 3.5' 14.0 3.5' 2017 January 14
C/2013 X1 (PANSTARRS) Centaurus 14.6 38" 14.6 39" 14.7 39" 2016 September 29
93P/Lovas Pisces 14.7 26" 14.8 25" 15.0 24" 2016 December 31
C/2011 KP36 (Spacewatch) Cetus 14.8 50" 14.9 49" 15.0 48" 2016 December 31
65P/Gunn Scorpius 14.9 1.3' 14.7 1.4' 14.5 1.5' 2017 January 4
C/2016 N4 (MASTER) Pisces 15.1 17" 15.0 17" 14.9 17" 2016 December 29

*In solar conjunction and generally 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
Weekly Information About Bright Comets
Cometography