British Astronomical Association

Comet Section

Director: Nick James

Visual observations page


(Co-ordinator Jonathan Shanklin)

Latest Discoveries

Mar 08  Worachate Boonplod reports two Meyer group comets in real time C2 images
Mar 10  Masanori Uchina reports a Kreutz group comet in real time C3 images
Mar 10  Krzysztof Kida reports a Kreutz group comet in real time C3 images
Mar 12  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Mar 12  Masanori Uchina reports a Kreutz group comet in real time C2 images
Mar 13  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Mar 14  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Mar 16  Cometary activity reported in Centaur asteroid 2014 OG392
Mar 18  Michal Kusiak reports a Kreutz group comet in real time C3 images
Mar 23  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Mar 23  Masanori Uchina reports a Kreutz group comet in real time C2 images
Mar 25  Cometary activity confirmed in 2019 U6
Mar 26  Discovery of 2020 F1 (P/Leonard) reported
Mar 26  Trygve Prestgard reports a Kreutz group comet in real time C2 images
Mar 26  Worachate Boonplod reports a Kreutz group comet in real time C2 images
Mar 27  Worachate Boonplod reports a Meyer group comet in real time C2 images
Mar 28  Cometary activity confirmed in 2019 S4
Mar 30  Trygve Prestgard reports four Kreutz group comets in archival C2 images
Apr 01  Discovery of 2020 F2 (ATLAS) reported
Apr 01  Discovery of 2020 F3 (NEOWISE) reported
Apr 04  Szymon Liwo reports a Kreutz group comet in real time C3 images
Apr 06  Discovery of 2020 F4 = 2011 GN5 (P/PanSTARRS) reported
Apr 06  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 2020 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 on April 1

Comet	                  Magnitude   Trend    Observable     When visible        Last visual observation
2019 Y4 (ATLAS)                7      bright   70 N to 10 S   all night           2020 March
2019 Y1 (ATLAS)                9      fade     70 N to 25 N   evening + morning   2020 April
2017 T2 (PanSTARRS)            9      steady   70 N to  5 N   all night           2020 March
2019 U6 (Lemmon)              11.5    bright   10 N to 75 S   evening             2020 March
88P/Howell                    13 ?    bright   60 N to 70 S   best midnight       Not yet observed
2018 N2 (ASASSN)              13      fade     70 N to 55 N   best morning        2020 January
29P/Schwassmann-Wachmann      13 ?    varies   Poor elongation                    2020 February

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

  1. Moonlight is now affecting observations of 2019 Y4.  At face value there has been a slowdown in the rate of brightening, however a wide range of apertures is in use, and many observers currently have to observe in light polluted skies.  The outer parts of the coma are faint and difficult to see with larger apertures or under poor conditions.  There is increasing evidence of strong non-gravitational effects in the astrometric observations and this may imply a small nucleus that is in the process of disintegrating.  The future brightness remains uncertain.  The graph below takes what is now an optimistic view, allowing for relatively rapid brightening.  It uses an absolute magnitude of 3.8 and 20 log r for the rate of brightening.  The uncertainty in brightness at the time of perihelion is large, though the worst case indicator is 2nd magnitude, but it could disappear well before perihelion.    It will remain well placed for UK observers into May.
  2. 2017 T2 is just within range of binocular observation, but requires large binoculars and/or dark skies.  It is unlikely to get much brighter than at present.  It will remain well placed for observation until 2020 October. 
  3. 2019 Y1 brightened quite rapidly but is now fading from its brightest at around 9th magnitude.  It will remain moderately well placed for UK observers.
  4. 2019 U6  is also brightening rapidly.  It won't become visible to UK observers until after perihelion.
  5. The comet predictions for 2020, 2021 and 2022 were updated or created in early January.
  6. 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 2019 December Journal included a paper on "The brighter comets of 2015".  Further papers in this series are in press (2016 - 2017).
  7. Thanks to the many observers who have sent 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 (updated January 4) 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.

Details

2017 T2


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 are available from Kazuo Kinoshita's Comet Orbit Home Page.  I compile orbital elements in Megastar format for: periodic comets , current comets , comets prior to 2005.  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.

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 2020 [updated 2020 January 11] , 2021 [updated 2020 January 11] and 2022 [created 2020 January 11] are published in the BAA Journal in December each year. This list [Updated 2020 April 2] gives the period of visibility and maximum brightness for comets that are predicted to be visible within the next five 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

Visual and visual equivalent magnitude observations should be sent to me at <jds [at] ast.com.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 2017 January 4).   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, 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, Jose Navarro Pina, Gabriel Oksa, Mieczyslaw  Paradowski, Nirmal Paul, Stuart Rae, Walter Robledo, Tony Scarmato, Willian Souza, David Strange Johan Warrell and Seiichi Yoshida, several of whom contribute observations from their colleagues.

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.


Published by jds@ast.cam.ac.uk