Comet Chasing in December


Comet chasing is the visual observation of telescopic comets.

News


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 December


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

45P/Honda-Mrkos-Pajdusakova: An evening comet visible in binoculars
This comet begins the month in Sagittarius at magnitude 12.0. Look for a 2.5' coma. It should brighten very rapidly, as bright as 7th magnitude by month's end, when it will be in Capricornus.  FINDER CHART
Latitude Visibility December 3 Visibility December 10 Visibility December 17 Visibility December 24 Visibility December 31 Nights Visible
55o N Not visible Not visible Very low in the southern sky during evening twilight at ~17:10 Very low in the southern sky during evening twilight at ~17:20 Very low in the western sky during evening twilight at ~17:30 1-
40o N Low in the western sky during evening twilight at ~18:00 Low in the southern sky during evening twilight at ~17:50 Low in the western sky during evening twilight at ~18:10 Low in the western sky during evening twilight at ~18:10 Very low in the western sky during evening twilight at ~18:10 1-
Equator Fairly high in the western sky during evening twilight at ~19:10 Fairly high in the western sky during evening twilight at ~19:00 Low 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 ~20:20 Low in the western sky during evening twilight at ~20:00 Low in the western sky during evening twilight at ~20:20 Low in the western sky during evening twilight at ~20:30 Very low in the western sky during evening twilight at ~20:20 1-

C/2016 U1 (NEOWISE): A northern hemisphere morning comet visible in small telescopes
This comet begins the month in Canes Venatici at magnitude 11.3. Look for a 3' coma. It should brighten rapidly, as bright as 8th magnitude by month's end, when it will be in Ophiuchus.  FINDER CHART
Latitude Visibility December 3 Visibility December 10 Visibility December 17 Visibility December 24 Visibility December 31 Nights Visible
55o N High at ~05:40 High at ~05:50 Fairly high during morning twilight at ~06:20 Fairly high in the eastern sky during morning twilight at ~06:10 Low in the eastern sky during morning twilight at ~06:20 1-
40o N High at ~05:20 Fairly high at ~05:30 Fairly high during morning twilight at ~05:50 Fairly high in the eastern sky during morning twilight at ~05:50 Low in the eastern sky during morning twilight at ~05:50 1-
Equator Low in the northern sky during morning twilight at ~04:40 Low in the eastern sky during morning twilight at ~04:50 Very low in the eastern sky during morning twilight at ~05:00 Very low in the eastern sky during morning twilight at ~05:00 Very low in the eastern sky during morning twilight at ~05:10 1-
30o S Not visible Not visible Not visible Not visible Not visible  

237P/LINEAR: An evening comet visible in a 6-inch (15 cm) telescope
This comet begins the month in Sagittarius at magnitude 9.9. Look for a 3' coma. It should fade slowly.  FINDER CHART
Latitude Visibility December 3 Visibility December 10 Visibility December 17 Visibility December 24 Visibility December 31 Nights Visible
55o N Very low in the western sky during evening twilight at ~17:20 Very low in the western sky during evening twilight at ~17:10 Very low in the western sky during evening twilight at ~17:10 Very low in the western sky during evening twilight at ~17:10 Very low in the western sky during evening twilight at ~17:10 1-
40o N Very low in the western sky during evening twilight at ~18:00 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 ~17:50 Very low in the western sky during evening twilight at ~17:50 1-
Equator 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 Very low in the western sky during evening twilight at ~18:50 Not visible 1-
30o S Very low in the western sky during evening twilight at ~19:50 Very low in the western sky during evening twilight at ~19:50 Not visible Not visible Not visible 1-18, 20-21

C/2015 V2 (Johnson): A northern hemisphere morning comet visible in small telescopes
This comet begins the month in Canes Venatici at magnitude 11.5. Look for a 2.5' coma. It should brighten by about 0.8 magnitudes, moving into Bootes by month's end.  FINDER CHART
Latitude Visibility December 3 Visibility December 10 Visibility December 17 Visibility December 24 Visibility December 31 Nights Visible
55o N High at ~05:40 High at ~05:50 High during morning twilight at ~06:10 High in moonlight at ~06:00 High at ~06:00 1-
40o N High at ~05:20 High at ~05:30 High during morning twilight at ~05:50 High in moonlight at ~05:40 High at ~05:40 1-
Equator Fairly high in the northern sky during morning twilight at ~04:40 Fairly high in the northern sky during morning twilight at ~04:40 Fairly high in the northern sky during morning twilight at ~04:50 Fairly high in the northern sky during morning twilight at ~04:40 Fairly high in the northern sky during morning twilight at ~04:50 1-
30o S Not visible Not visible Not visible Not visible Not visible  

144P/Kushida: A morning comet visible in a 16-inch (41 cm) telescope
This comet begins the month in Virgo at magnitude 11.7. Look for a 3.5' coma. It should fade by about 0.8 magnitudes by month's end.  FINDER CHART
Latitude Visibility December 3 Visibility December 10 Visibility December 17 Visibility December 24 Visibility December 31 Nights Visible
55o N Fairly high in the southern sky at ~05:50 Fairly high in the southern sky at ~06:00 Fairly high in the southern sky during morning twilight at ~06:20 Fairly high in the southern sky in moonlight at ~06:00 Fairly high in the southern sky at ~06:00 1-
40o N Fairly high at ~05:30 Fairly high at ~05:30 Fairly high during morning twilight at ~05:50 Fairly high in moonlight at ~05:40 Fairly high at ~05:40 1-
Equator High at ~04:30 High at ~04:30 High during morning twilight at ~04:50 High in moonlight at ~04:40 High at ~04:40 1-
30o S Fairly high in the eastern sky during morning twilight at ~03:20 Fairly high in the eastern sky during morning twilight at ~03:20 Fairly high during morning twilight at ~03:30 Fairly high during morning twilight at ~03:20 High at ~03:30 1-

43P/Wolf-Harrington: A morning comet visible in a 16-inch (41 cm) telescope
This comet begins the month in Crater at magnitude 13.1. Look for a 1' coma. It should fade by about 0.6 magnitudes, moving into Corvus by month's end.  FINDER CHART
Latitude Visibility December 3 Visibility December 10 Visibility December 17 Visibility December 24 Visibility December 31 Nights Visible
55o N Low in the southern sky at ~05:50 Low in the southern sky at ~05:50 Low in the southern sky during morning twilight at ~06:10 Low in the southern sky in moonlight at ~05:50 Low in the southern sky at ~05:30 1-
40o N Fairly high at ~05:20 Fairly high at ~05:30 Fairly high during morning twilight at ~05:50 Fairly high in the southern sky in moonlight at ~05:30 Fairly high in the southern sky at ~05:30 1-
Equator High at ~04:30 High at ~04:30 High during morning twilight at ~04:40 High in moonlight at ~04:30 High at ~04:40 1-
30o S Fairly high during morning twilight at ~03:20 High at ~03:20 High during morning twilight at ~03:30 High in moonlight at ~03:20 High at ~03:20 1-

C/2011 KP36 (Spacewatch): An evening comet visible in a 16-inch (41 cm) telescope
This comet begins the month in Cetus at magnitude 13.3. Look for a 60" coma. It should fade slowly.  FINDER CHART
Latitude Visibility December 3 Visibility December 10 Visibility December 17 Visibility December 24 Visibility December 31 Nights Visible
55o N Fairly high in the southern sky at ~19:40 Fairly high in the southern sky in moonlight at ~19:10 Fairly high in the southern sky at ~18:50 Fairly high at ~18:30 Fairly high at ~18:20 1-
40o N High at ~20:10 High in moonlight at ~19:10 High at ~18:50 High at ~18:40 High at ~18:30 1-
Equator High in moonlight at ~19:40 High in moonlight at ~19:10 High at ~19:30 High at ~19:30 High at ~19:30 1-
30o S High in moonlight at ~20:30 High during evening twilight at ~20:20 High at ~20:40 High at ~20:40 High at ~20:40 1-

C/2015 ER61 (PANSTARRS): A morning comet visible in an 18-inch (46 cm) telescope
This comet begins the month in Virgo at magnitude 13.8. Look for a 1.5' coma. It should brighten by about 0.8 magnitudes, moving into Libra by month's end.  FINDER CHART
Latitude Visibility December 3 Visibility December 10 Visibility December 17 Visibility December 24 Visibility December 31 Nights Visible
55o N Very low in the eastern sky during morning twilight at ~06:10 Very low in the southern sky during morning twilight at ~06:10 Low in the southern sky during morning twilight at ~06:30 Low in the southern sky during morning twilight at ~06:20 Low in the southern sky during morning twilight at ~06:20 1-
40o N Low in the eastern sky during morning twilight at ~05:40 Low in the eastern 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 ~05:50 Low in the southern sky during morning twilight at ~05:50 1-
Equator Low in the eastern sky during morning twilight at ~04:40 Fairly high in the eastern sky during morning twilight at ~04:40 Fairly high in the eastern sky during morning twilight at ~04:50 Fairly high in the eastern sky during morning twilight at ~04:40 Fairly high at ~04:40 1-
30o S Low in the eastern sky during morning twilight at ~03:30 Low in the eastern sky during morning twilight at ~03:30 Low in the eastern sky during morning twilight at ~03:40 Fairly high in the eastern sky during morning twilight at ~03:30 Fairly high in the eastern sky during morning twilight at ~03:30 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

December 1st

December 15th

December 31st

Observations as of (UT)
Mag Diam Mag Diam Mag Diam
237P/LINEAR Sagittarius 9.9 2.9' 10.0 2.8' 10.1 2.8' 2016 November 17
C/2016 U1 (NEOWISE) Canes Venatici 11.1 3.3' 9.9 3.5' 8.1 2.8' 2016 December 1
C/2015 V2 (Johnson) Canes Venatici 11.4 2.1' 11.1 2.2' 10.7 2.5' 2016 November 30
45P/Honda-Mrkos-Pajdusakova Sagittarius 11.6 1.3' 9.4 1.6' 7.1 2.4' 2016 December 1
144P/Kushida Virgo 11.7 3.5' 12.0 3.6' 12.5 3.7' 2016 December 2
43P/Wolf-Harrington Crater 13.1 1.0' 13.4 1.1' 13.7 1.1' 2016 December 2
C/2011 KP36 (Spacewatch) Cetus 13.3 60" 13.4 57" 13.6 54" 2016 November 22
C/2015 ER61 (PANSTARRS) Virgo 13.8 1.1' 13.5 1.2' 13.1 1.3' 2016 November 19
C/2015 TQ209 (LINEAR) Libra 13.8 22" 14.1 22" 14.4 22" 2016 January 30
C/2013 X1 (PANSTARRS) Centaurus 14.3 34" 14.4 34" 14.5 34" 2016 September 29
315P/LONEOS Leo 14.8 1.3' 14.6 1.4' 14.5 1.5' 2016 October 9

*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