British Astronomical Association

Comet Section

Director: Nick James

Visual observations page

(Co-ordinator Jonathan Shanklin)

Latest Discoveries and news

Feb 24  Discovery of 2018 S3 (TESS) finally confirmed
Feb 28  Discovery of 2023 A3 (Tsuchinshan-ATLAS) reported
Mar 06  Zesheng Yang reports a Kreutz group comet in real time C3 images
Mar 06  Hanjie Tan reports a Kreutz group comet in real time C3 images
Mar 12  Discovery of 2023 E1 (ATLAS) reported
Mar 14  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Mar 14  Hanjie Tan reports a Kreutz group comet in real time C3 images
Mar 16  Designation change of 1951 G1 (Groeneveld) reported
Mar 18  Jiangao Ruan reports two Kreutz group comets in real time C2 images
Mar 19  Worachate Boonplod reports a Kreutz group comet in real time C2 images
Mar 21  Hanjie Tan reports a Meyer group comet in real time C3 images
Mar 21  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Mar 23  Update

If there have been no recent updates try The German comet group page or Seiichi Yoshida's page for information or the Liga Iberoamericana de Astronomia for observations.

Elsewhere on these pages: Highlights / Newly discovered comets / Periodic comets / Contributing observations / Comet Ephemerides / Upcoming Comets / Observing Comets / Links / Meetings / Publications / Comments and Contacts / Old 2023 News / Comet discovery procedure / Weather information / The Comet's Tale / BAA Comet Section image archive / Project Alcock / More information / Legacy page / Main BAA Comet Section page

Current comet magnitudes and observable region for 2023 March

Comet	                  Magnitude   Trend     Observable     When visible        Last visual observation
2017 K2 (PanSTARRS)            9      fade      10 N to 70 S   evening             2023 February
2022 A2 (PanSTARRS)           10      fade      75 N to 30 N   evening + morning   2023 March
2022 E3 (ZTF)                 10      fade      60 N to 65 S   evening             2023 March
2020 V2 (ZTF)                 10.5    fade      75 N to  0 S   evening             2023 March
2019 U5 (PanSTARRS)           11.5    bright    65 N to 65 S   best morning        2023 March
2019 L3 (ATLAS)               11.5    fade      30 N to 65 S   all night           2023 February
2020 K1 (PanSTARRS)           12.5    bright     0 N to 65 S   morning             2022 October
237P/LINEAR                   13      bright    35 N to 65 S   morning             Not yet observed
2019 T4 (ATLAS)               13      steady    65 N to 50 S   morning             2023 February
81P/Wild                      13      fade      50 N to 65 S   early morning       2023 February
29P/Schwassmann-Wachmann      13 ?    varies    80 N to 30 S   best evening        2023 January
2022 U2 (ATLAS)               13.5    fade      75 N to 45 S   evening             2023 February
96P/Machholz                  13.5    fade      Poor elongation                    2023 February
118P/Shoemaker-Levy           14      fade      80 N to 45 S   best evening        2023 February
2021 Y1 (ATLAS)               14      fade      35 N to 55 S   evening             2023 February

Details are usually fully updated at the beginning of each month, but some minor updates may be made more frequently, particularly for brighter comets. The last (partial) update was on March 16. The magnitude is a rough value for the mean magnitude reported; some observers will see the comet brighter than this, whilst others will see it fainter. The observable region is an approximate indication of the latitude at which the comet may be seen. Under good conditions comets may be visible outside this range. The period when visible is for the UK if the comet is visible from the UK, otherwise for 40 S or the Equator as appropriate. The last visual observation is as received by the Section, details are often updated on the basis of observations published elsewhere. Beginners will often find comets fainter than about 7th magnitude difficult to locate - see below for information on positions and finder charts.

Highlights and News

2017 K2 has passed its brightest and is at a high southern declination.
2022 E3 is fading rapidly. It and 2020 V2 are relatively easy telescopic objects.
Newly discovered comet 2023 A3 is likely to cause much speculation, indeed this is already happening. The comet is still 7.2 au from the Sun and the error bars on the extrapolated magnitude at perihelion are huge - more than 60 magnitudes! There are only nine observations in COBS and only two of those include a coma diameter. Even assuming a rate of brightening the comet could be anything from a naked eye object to one only visible in binoculars. I suggest waiting for more observations and for the comet to get closer to the Sun first.
There will be a BAA Comet Section meeting in London on 2023 July 8. This will be held at the National Maritime Museum.
The Section welcomes observations from all comet enthusiasts, whether members of the BAA or not. An advantage of joining the BAA is that you can read papers on comets published in the BAA Journal. The 2022 December Journal included a paper on "The brighter comets of 2019". Further papers in this series (2020) and a paper drawing conclusions from the series are in press, with that for 2021 being prepared. Best wishes go to our colleagues in the Ukraine.

Details

Details of the discovery, observations and analyses of new comets which were discovered during 1995 , 1996 , 1997 , 1998 , 1999 , 2000 , 2001 , 2002 , 2003 , 2004 , 2005 , 2006 , 2007 , 2008 , 2009 , 2010 , 2011 , 2012 , 2013 , 2014 , 2015 , 2016 , 2017 [updated 2021 November 3], 2018 [updated 2023 March 3] , 2019 [updated 2023 February 14] , 2020 [updated 2023 March 22] , 2021 [updated 2023 February 10] , 2022 [updated 2023 February 20] , 2023 [updated 2023 March 17] . Note that in general only details of brighter currently visually observable comets are updated and that analyses of the brighter comets of past years will be published in the BAA Journal.
Details, observations and analyses of periodic comets numbered 1 - 100 [updated 2023 March 21], 101 - 199 [updated 2022 October 3], 200 - 299 [updated 2022 August 7], 300 - 399 [updated 2022 February 2], 400 - 499 [updated 2023 March 22] and cometary asteroids, potentially numberable comets and periodic SOHO comets [updated 2023 March 23].
A list of SOHO comets discovered during 2000 , 2001 , 2002 , 2003 , 2004 , 2005 , 2006 , 2007 , 2008 , 2009 , 2010 , 2011 , 2012 , 2013 , 2014 , 2015 , 2016 , 2017 , 2018 , 2019 , 2020 , 2021 [updated 2022 June 29] , 2022 [updated 2023 February 7] , 2023 [updated 2023 March 22] and SOHO X/ comets.
Observations submitted in ICQ format for comets of 2006 , 2007 , 2008 , 2009 , 2010 , 2011 , 2012 , 2013 , 2014 , 2015 , 2016 , 2017 , 2018 , 2019 , 2020 , 2021 [updated 2022 December 2], 2022 [updated 2023 February 3], 2023 [updated 2023 March 1]. Observations submitted or published in ICQ. Observations in COBS.
Light curves of comets that may become brighter than 8th magnitude (aperture corrected for potential naked eye comets) [click on thumbnail to get the full scale image, updated on 2023 January 3]. The dotted lines represent 99% confidence limits. 2017 K2, 2020 V2, 2022 A2, 2022 E3.
Comet magnitude parameters [ updated 2023 March 1].
Full IAUC details of SOHO Kreutz group and other comets announced during 2000 , 2001 , 2002 , 2003 , 2004 , 2005 , 2006 , 2007 , 2008 , 2009 .
General information on Kreutz and sun approaching comets [updated 2022 February 3], on LASCO, STEREO and the Kreutz comets and a list of all SOHO comets [updated 2016 June 2].
Daily news from 1999 / 2000 / 2001 / 2002 / 2003 / 2004 / 2005 / 2006 / 2007 / 2008 / 2009 / 2010 / 2011 / 2012 / 2013 / 2014 / 2015 / 2016 / 2017 / 2018 / 2019 / 2020 / 2021 / 2022 / 2023 /
Maik Meyer's comet mailing list
Contact Nick James <ndj [at] nickdjames.com> to be added to the distribution list for the BAA Comet Section electronic discussion forum.

Comet ephemerides (positions) etc

For positions of newly discovered comets see the NEO confirmation page . You can also generate your own ephemerides and elements at the CBAT Minor Planet and Comet Ephemeris Service web page. The elements and ephemerides from the JPL Small-Body Database Browser give estimates of the errors, which are often far larger than might be thought from the accuracy of the elements given by the CBAT. Seiichi Yoshida has pages for currently visible comets, which include finder charts. Seiichi also has a comet rendezvous page, which lists conjunctions between comets, variable stars and nebulae and a comet recovery page, which lists periodic comets not yet recovered at the present return. The T3 project aims to discover comets amongst the population of asteroids influenced by Jupiter.

Planning aids and information for forthcoming comets, valid out to about 2025.

Comets reaching within three degrees of 180° opposition [updated 2013 December 31]
Comets reaching within three degrees of zero phase angle [updated 2013 December 31]

The MPC also has a list of the last observation for all comets. Electronic observers should try and observe any comets that have not recently been observed according to the CBAT but which are expected to be within range of their equipment. Negative observations are also useful. In addition, the MPC has orbital elements for unusual asteroids, many of which have cometary orbits.

Finder charts

The BAA Computing Section has online charts for the comets listed here. There are daily finder charts for bright comets at Heavens Above. Reinder Bouma and Edwin van Dijk's astrosite Groningen has an excellent set of finder charts for brighter comets, which also show suitable comparison stars.

Orbits etc

The elements and ephemerides from the JPL Small-Body Database Browser give estimates of the errors, which are often far larger than might be thought from the accuracy of the elements given by the CBAT. Full details of the latest orbits were available from Kazuo Kinoshita's Comet Orbit Home Page (Kazuo died in 2021 July and his web page hadn't been updated since 2020 February). I compile orbital elements in Megastar format for: numbered periodic comets , recent comets (updated 2023 March 3) and comets prior to 2006. Most of the more recent elements include the latest magnitude parameters. The elements are from a mix of CBAT catalogues, MPC, MPEC, JPL and individual orbit computers. Older elements are for the epoch of perihelion, but most recent elements from the MPEC are for epoch of date.

Downloads etc

Download Richard Fleet's GraphDark software for graphically displaying comet (and other object) visibility. Latest version is 2.05, 2007 May.

Download William Schwittek's CometWin software for generating comet ephemerides and visibility diagrams. [Updated 2002 March 5]

Download Solex, N-body solar system dynamics software.

Upcoming comets

Predictions for the comets expected to return in 2022 [updated 2022 January 7], 2023 [Updated 2022 October 20], 2024 [Updated 2022 November 6] and 2025 [Created 2022 October 20] are published in the BAA Journal in December each year. This list [Updated 2023 March 1] gives the period of visibility and maximum brightness for comets that are predicted to be brighter than 12th magnitude within the next few years. A few are listed further into the future. Seiichi Yoshida also has a list of comets likely to be visible in the next five years.

Contributing observations

Observations may be used in the reports on comets which appear on these pages, in The Comet's Tale and in the BAA Journal. Guidance on observing is given in the BAA Comet Observing Guide

Thanks to the many observers who do send in their observations in ICQ format. Imagers are encouraged to reduce their observations to equivalent visual magnitude (see Project Alcock ) and submit them in this format. Do check the observation files to see if what you sent matches what is there, as I still have to edit some of the submitted records, particularly the position of "m" when tail length is given in minutes, the focal ratio and the designation of periodic comets 1-99. If your observations are missing it may be because you have not used the correct format, which includes ICQ as a key. If you use the Comet Observation Database to enter your observations they will be formatted correctly, but please send them to me for inclusion in TA.

Visual and visual equivalent magnitude observations should be sent to me at <jds [at] ast.cam.ac.uk> in simple text format. Visual observers can use the BAA visual report form to log observations. To avoid the use of multiple formats the ICQ format , which uses special keys to code observation particulars, is now standardised as the one to use for submission and archiving of observations. The ICQ have not updated their observation keys since 2010, so these additional keys are suggested for use when submitting observations to the BAA (updated 2020 October 3). Crni Vhr Observatory has launched the Comet Observation Database which allows entry of observations in ICQ format, and plots of light curves. Visual observations entered using this system should be emailed to me at the end of the month. Observations are usually analysed and sent to TA as soon as possible after the end of the month with a TA deadline of the 2nd; any late observations will be used in subsequent analyses. Observations will continue to be published by Guy Hurst in The Astronomer magazine in TA format. There is also a visual drawing form. The German comet group also has a computer program that will correctly format observations for the ICQ [2009 December].

Images should be sent to Denis Buczynski.

Regular contributors include James Abbott, Jose Aguiar, Alexander Amorim, Nicolas Biver, Denis Buczynski, Paul Camilleri, Peter Carson, Matyas Csukas, Roger Dymock, John Fletcher, Marco Goiato, Juan Gonzalez, Bjorn Granslo, Werner Hasubick, Kevin Hills, Nick James, Heinz Kerner, Carlos Labordena, Rolando Ligustri, Michael Mattiazzo, Maik Mayer, Antonio Milani, Martin Mobberley, Giuseppe Pappa, Jose Navarro Pina, Gabriel Oksa, Mieczyslaw Paradowski, Nirmal Paul, Stuart Rae, Walter Robledo, Tony Scarmato, Willian Souza, David Strange, Johan Warrell, Chris Wyatt and Seiichi Yoshida, several of whom contribute observations from their colleagues. Thanks are due to all of them.

Warning I receive a large number of emails containing viruses or other junk. Please try and make clear that your message is legitimate, otherwise it may be deleted without being read. It is advisable to use your own name, rather than an alias, in the 'from' field and use an obvious, recent subject.

Comments and contact

Many thanks to those that regularly access this page for your interest. If you have any comments, suggestions for improvement or find any problems, please email the visual co-ordinator, Jon Shanklin, at j.shanklin @ bas.ac.uk. If you need to phone me, my home number is +44 (0)1223 571250 or my BAS number is +44 (0)1223 221482. Snail mail will reach me at the British Antarctic Survey, Madingley Road, CAMBRIDGE CB3 0ET, England. For information about my work with BAS see my web page at BAS. There is a small piece of Antarctica named as Shanklin Glacier. See also this BBC report. Exploration of icy parts of the world clearly runs in the blood as my great-grandfather kept diaries which record the passage of a comet below the Plough, the discovery of a comet by his brother, Bernard Thomas, from Tasmania and the expeditions to Antarctica by Scott and Shackleton. A write up of my George Alcock lecture, which tells a little of the Antarctic story was published in the 2021 October BAA Journal.

Published by jds@ast.cam.ac.uk