Comet Chasing in February


Comet chasing is the visual observation of telescopic comets.

News


  • C/2017 T1 (Heinze) was discovered by Ari Heinze on ATLAS survey images. C/2017 T1 will reach perihelion in late February. It will  pass within 0.2 AU of the earth on January 4. This comet exceeds the Bortle limit, which means that it is unlikely to survive perihelion passage.

  • 174P/Echeclus had an outburst on December 8, brightening by several magnitudes. As of December 11, a small 20" coma has appeared, which is expected to grow in the coming days. Previous outbursts occurred in 2005 and 2011. Echeclus is a Centaur object that is capable of comet-like outbursts far from the sun. 

  • C/2016 N6 (PANSTARRS) will reach perihelion in mid July. It is predicted to reach maximum brightness of magnitude 12.5 in late June.

  • 24P/Schaumasse passed perihelion in mid November. This comet was discovered in 1911 and has a 7.1 year orbital period. It has a long and interesting history, often "hit and miss," when it will be observed for several apparitions and then go missing for several more. Schaumasse was not observed in 2001 or 2009, but has roared back this year as bright a ever. Click here for a detailed history. 

  • C/2017 O1 (ASASSN) was a new discovery on July 19 by the All-Sky Automated Survey for Supernovae (ASASSN) program. This program is designed to discover supernovae. This is its first comet discovery. It passed perihelion in mid October, at which time the comet passed within 0.7 AU of the earth. 

  • 62P/Tsuchinshan was recovered in August. It had not been seen since 2004. It brightened significantly and passed perihelion in late November. It is now too close to the sun to be observed.

  • 29P/Schwassmann-Wachmann was very active in late August and September. It had the second of two outbursts that occurred within a few days of one another. This second outburst was the brightest since 2010, brightening it up to 12th magnitude. On July 2 in had an outburst that for the first time was caught as the outburst occurred (see https://www.britastro.org/node/10684). Primary outbursts, resulting in a brightening of 0.5 - 1.0 magnitudes, occur roughly every 59 days, typically taking 5-10 days to subside. But up to three subsequent outbursts, such as the one ones recently, may occur 5-10 days afterward, each typically smaller than the last, but sometimes they can be even brighter than the first. 

  • C/2015 V2 (Johnson) passed perihelion in mid June and is fading. 

  • C/2015 ER61 (PANSTARRS) passed perihelion in early May and is on the way out and is only visible in large telescope. It had an outburst in early April, brightening by 1- 2 magnitudes. 

  • C/2017 K2 (PANSTARRS) was discovered by the PANSTARRS survey in May 2017. This comet was discovered at an unusually large distance, over 16 AU from the sun! It is currently magnitude 19, which is bright for that distance. It won't pass perihelion until October of 2023, apparently at distance of 1.7 AU from the sun. This might possibly be a Great Comet... or not. We will just have to wait (and wait, and wait, and wait) and see.  

Read about the first interstellar object to pass through our solar system

 

 

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)

C/2017 T1 (Heinze): A northern hemisphere evening comet visible in small telescopes
This comet begins the month in Pegasus at magnitude 10.3. Look for a 2' coma. It should fade slowly.  FINDER CHART
Latitude Visibility February 3 Visibility February 10 Visibility February 17 Visibility February 24 Visibility March 3 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 eastern sky during morning twilight at ~05:30 Low in the eastern sky during morning twilight at ~05:10 Low in the eastern sky during morning twilight at ~05:20 1-
40o N Low in the western sky during evening twilight at ~18:50 Very low in the western sky during evening twilight at ~18:50 Very low in the eastern sky during morning twilight at ~05:30 Very low in the eastern sky during morning twilight at ~05:20 Low in the eastern sky during morning twilight at ~05:20 1-
Equator Not visible Not visible Not visible Not visible Very low in the eastern sky during morning twilight at ~05:20 24-
30o S Not visible Not visible Not visible Not visible Not visible  

C/2016 N6 (PANSTARRS): A northern hemisphere morning comet visible in a 6-inch (15 cm) telescope
This comet begins the month in Draco at magnitude 12.8. Look for a 35" coma. It should brighten slowly, moving into Ursa Minor by month's end.  FINDER CHART
Latitude Visibility February 3 Visibility February 10 Visibility February 17 Visibility February 24 Visibility March 3 Nights Visible
55o N Fairly high at ~20:50 High at ~04:50 High at ~04:50 High at ~04:20 High during evening twilight at ~19:40 1-
40o N Low in the northern sky at ~21:00 High at ~03:50 High at ~05:00 High at ~04:20 Fairly high at ~19:40 1-
Equator Fairly high in the northern sky during morning twilight at ~05:10 Low in the northern sky in moonlight at ~05:00 Low in the northern sky at ~04:50 Low in the northern sky at ~04:20 Low in the northern sky in moonlight at ~03:00 1-
30o S Not visible Not visible Not visible Not visible Not visible  

C/2016 R2 (PANSTARRS): An evening comet visible in an 8-inch (20 cm) telescope
This comet begins the month in Taurus at magnitude 11.3. Look for a 3.5' coma. It should fade slowly.  FINDER CHART
Latitude Visibility February 3 Visibility February 10 Visibility February 17 Visibility February 24 Visibility March 3 Nights Visible
55o N High at ~19:10 High at ~19:20 High at ~19:20 High during evening twilight at ~19:20 High during evening twilight at ~19:40 1-
40o N High at ~19:10 High at ~19:10 High at ~19:20 High during evening twilight at ~19:10 High at ~19:30 1-
Equator High at ~19:40 High at ~19:40 High at ~19:40 High during evening twilight at ~19:20 High at ~19:30 1-
30o S Fairly high at ~20:30 Fairly high in the northern sky at ~20:20 Fairly high in the northern sky during evening twilight at ~20:10 Fairly high in the northern sky during evening twilight at ~19:50 Low in the northern sky during evening twilight at ~19:50 1-

C/2015 O1 (PANSTARRS): A morning comet visible in an 8-inch (20 cm) telescope
This comet begins the month in Hercules at magnitude 12.7. Look for a 1.5' coma. It should brighten slowly.  FINDER CHART
Latitude Visibility February 3 Visibility February 10 Visibility February 17 Visibility February 24 Visibility March 3 Nights Visible
55o N High during morning twilight at ~05:50 High at ~04:50 High at ~05:00 High at ~04:50 High during morning twilight at ~04:50 1-
40o N High during morning twilight at ~05:40 High in moonlight at ~05:20 High at ~05:10 High at ~05:00 High during morning twilight at ~05:00 1-
Equator High during morning twilight at ~05:10 High in moonlight at ~05:00 High at ~05:00 High at ~04:50 High during morning twilight at ~05:00 1-
30o S Low in the northern sky during morning twilight at ~04:30 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 ~04:30 Low in the northern sky during morning twilight at ~04:50 1-

185P/Petriew: An evening comet visible in a 12.5-inch (32 cm) telescope
This comet begins the month in Pisces at magnitude 11.6. Look for a 2' coma. It should fade slowly.  FINDER CHART
Latitude Visibility February 3 Visibility February 10 Visibility February 17 Visibility February 24 Visibility March 3 Nights Visible
55o N Low in the western sky during evening twilight at ~18:40 Low in the western sky during evening twilight at ~19:00 Low in the western sky during evening twilight at ~19:10 Fairly high in the western sky during evening twilight at ~19:10 Fairly high in the western sky during evening twilight at ~19:40 1-
40o N Fairly high in the western sky during evening twilight at ~18:50 Fairly high in the western sky at ~19:00 Fairly high in the western sky at ~19:10 Fairly high in the western sky during evening twilight at ~19:10 Fairly high in the western sky at ~19:20 1-
Equator Fairly high in the western sky during evening twilight at ~19:30 Fairly high in the western sky at ~19:30 Fairly high in the western sky at ~19:30 Fairly high during evening twilight at ~19:20 Fairly high at ~19:30 1-
30o S Low in the western sky during evening twilight at ~20:10 Low in the western sky during evening twilight at ~20:10 Low in the western sky during evening twilight at ~20:00 Low in the western sky during evening twilight at ~19:50 Low in the western sky during evening twilight at ~19:50 1-

C/2016 M1 (PANSTARRS): A morning comet visible in a 14-inch (36 cm) telescope
This comet begins the month in Serpens Cauda at magnitude 13.4. Look for a 1.5' coma. It should brighten by about 0.5 magnitudes, moving into Aquila by month's end.  FINDER CHART
Latitude Visibility February 3 Visibility February 10 Visibility February 17 Visibility February 24 Visibility March 3 Nights Visible
55o N Fairly high in the eastern sky during morning twilight at ~06:00 Low in the eastern sky during morning twilight at ~05:30 Low in the eastern sky during morning twilight at ~05:20 Low in the eastern sky during morning twilight at ~05:00 Fairly high in the eastern sky during morning twilight at ~05:10 1-
40o N Fairly high in the eastern sky during morning twilight at ~05:50 Fairly high in the eastern sky during morning twilight at ~05:30 Fairly high in the eastern sky during morning twilight at ~05:20 Fairly high in the eastern sky at ~05:10 Fairly high during morning twilight at ~05:10 1-
Equator 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 at ~05:00 Fairly high at ~05:00 Fairly high during morning twilight at ~05:10 1-
30o S Not visible Very low in the eastern sky during morning twilight at ~04:30 Low in the eastern sky during morning twilight at ~04:30 Fairly high in the eastern sky during morning twilight at ~04:30 Fairly high in the eastern sky during morning twilight at ~04:50 1-

C/2017 O1 (ASASSN): A northern hemisphere evening comet visible in a 16-inch (41 cm) telescope
This comet begins the month in Cepheus at magnitude 12.0. Look for a 2.5' coma. It should fade by about 0.9 magnitudes, moving into Camelopardus by month's end.  FINDER CHART
Latitude Visibility February 3 Visibility February 10 Visibility February 17 Visibility February 24 Visibility March 3 Nights Visible
55o N High at ~19:50 High at ~20:00 High at ~20:10 High at ~03:40 High during evening twilight at ~19:40 1-
40o N High at ~19:50 High at ~20:00 High at ~20:00 Fairly high at ~02:50 High at ~19:40 1-
Equator Very low in the northern sky at ~19:50 Very low in the northern sky at ~20:00 Low in the northern sky at ~20:00 Low in the northern sky in moonlight at ~19:50 Low in the northern sky at ~19:50 1-
30o S Not visible Not visible Not visible Not visible Not visible  

62P/Tsuchinshan: A morning comet visible in very large telescopes
This comet begins the month in Virgo at magnitude 12.8. Look for a 3.5' coma. It should fade by about 0.9 magnitudes by month's end.  FINDER CHART
Latitude Visibility February 3 Visibility February 10 Visibility February 17 Visibility February 24 Visibility March 3 Nights Visible
55o N Fairly high in moonlight at ~05:40 Fairly high at ~04:50 Fairly high at ~04:40 Fairly high at ~04:10 Fairly high in moonlight at ~04:10 1-
40o N High in moonlight at ~05:30 High at ~03:50 High at ~04:40 High at ~04:10 High in moonlight at ~04:10 1-
Equator High during morning twilight at ~05:00 High in moonlight at ~04:50 High at ~04:40 High at ~04:10 High in moonlight at ~04:00 1-
30o S High during morning twilight at ~04:20 High in moonlight at ~04:00 High at ~04:10 High at ~04:10 High in moonlight at ~04:00 1-

C/2015 V2 (Johnson): A southern hemisphere evening comet visible in very large telescopes
This comet begins the month in Grus at magnitude 13.8. Look for a 1.5' coma. It should fade slowly. The best visibility is early in the month as seen from the southern hemisphere.  FINDER CHART
Latitude Visibility February 3 Visibility February 10 Visibility February 17 Visibility February 24 Visibility March 3 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 Not visible Not visible Not visible Not visible Not visible  
30o S Low in the southern sky during evening twilight at ~20:20 Low in the southern sky during evening twilight at ~20:10 Low in the southern sky during evening twilight at ~20:10 Low in the southern sky during evening twilight at ~19:50 Low in the southern sky during evening twilight at ~19:50 1-

C/2017 K6 (Jacques): An evening comet visible in very large telescopes
This comet begins the month in Cetus at magnitude 13.8. Look for a 1' coma. It should fade slowly, moving into Eridanus by month's end.  FINDER CHART
Latitude Visibility February 3 Visibility February 10 Visibility February 17 Visibility February 24 Visibility March 3 Nights Visible
55o N Low in the southern sky during evening twilight at ~18:40 Low in the southern sky during evening twilight at ~19:00 Low in the southern sky during evening twilight at ~19:10 Fairly high in the southern sky during evening twilight at ~19:10 Low in the western sky during evening twilight at ~19:40 1-
40o N Fairly high in the southern sky at ~19:00 Fairly high in the southern sky at ~19:00 Fairly high in the southern sky at ~19:20 Fairly high during evening twilight at ~19:10 Fairly high in the western sky at ~19:30 1-
Equator High at ~19:40 High at ~19:30 High at ~19:30 High during evening twilight at ~19:20 High at ~19:30 1-
30o S High at ~20:30 High at ~20:20 High at ~20:10 Fairly high during evening twilight at ~19:50 Fairly high during evening twilight at ~19:50 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

February 1st

February 15th

February 28th

Observations as of (UT)
Mag Diam Mag Diam Mag Diam
C/2017 T1 (Heinze) Pegasus 10.3 2.3' 10.1 1.6' 10.5 1.4' 2018 January 18
C/2016 R2 (PANSTARRS) Taurus 11.3 3.5' 11.4 3.3' 11.5 3.1' 2018 January 23
185P/Petriew Pisces 11.6 2.1' 11.7 2.2' 12.0 2.1' 2018 January 18
C/2017 O1 (ASASSN) Cepheus 12.0 2.7' 12.5 2.4' 12.9 2.2' 2018 January 18
C/2015 O1 (PANSTARRS) Hercules 12.7 1.3' 12.6 1.4' 12.5 1.4' 2018 January 18
62P/Tsuchinshan Virgo 12.8 3.2' 13.3 3.3' 13.7 3.4' 2018 January 21
C/2016 N6 (PANSTARRS) Draco 12.8 35" 12.6 36" 12.5 38" 2018 January 17
C/2016 M1 (PANSTARRS) Serpens Cauda 13.4 1.1' 13.1 1.2' 12.8 1.3' 2017 December 13
C/2015 V2 (Johnson) Grus 13.8 1.6' 14.0 1.5' 14.2 1.5' 2018 January 16
C/2017 K6 (Jacques) Cetus 13.8 1.2' 14.0 1.1' 14.3 1.0' 2018 January 23
24P/Schaumasse Libra 14.1 1.0' 15.1 1.0' 16.0 1.1' 2018 January 21
174P/Echeclus Aries 14.7 47" 14.8 45" 14.8 44" 2018 January 20

*In solar conjunction and generally not visible

For information about specific 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