British Astronomical Association

Comet Section

Director: Nick James

Visual observations page

(Co-ordinator Jonathan Shanklin)

Latest Discoveries

Aug 24  Masanori Uchina reports a Kreutz group comet in real time C3 images
Aug 28  Zhijian Xu reports a Kreutz group comet in real time C3 images
Aug 29  Worachate Boonplod reports three Kreutz group comets in real time C3 images
Sep 01  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Sep 02  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Sep 03  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Sep 05  Zhijian Xu reports a Kreutz group comet in real time C3 images
Sep 08  Recovery of 2001 R6 (P/LINEAR-SKiff) as 2018 R1 by Erwin Schwab reported
Sep 08  Masanori Uchina reports a Kreutz group comet in real time C3 images
Sep 12  Zhijian Xu reports a Kreutz group comet in real time C3 images
Sep 14  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Sep 16  Recovery of 2008 O2 (P/McNaught) as 2018 P6 by Gareth Williams reported
Sep 16  Recovery of 2011 W2 (P/Rinner) as 2018 R2 by J-F Soulier and Krisztian Sarneczky reported
Sep 16  Discovery of 2018 R3 (Lemmon) reported
Sep 16  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Sep 16  Discovery of 2018 R4 (Fuls) reported
Sep 18  Recovery of 2007 V1 (P/Larson) as 2018 S1 by Krisztian Sarneczky and Robert Szakats reported
Sep 18  Discovery of 2018 R5 (Lemmon) reported
Sep 19  Zhijian Xu reports a Kreutz group comet in real time C3 images
Sep 20  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 2018 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 (September 2) and observable region (September 1)

Comet	                  Magnitude   Trend    Observable     When visible        Last visual observation
21P/Giacobini-Zinner           7      steady   65 N to 30 S   all night           2018 September
PanSTARRS (2017 S3)            8      fade?    Conjunction                        2018 August
PanSTARRS (2016 M1)            9.5    fade      5 N to 85 S   evening             2018 August
NEOWISE (2018 N1)             10      fade     35 N to 65 S   evening             2018 September
38P/Stephan-Oterma            10.5    bright   65 N to 60 S   morning             2018 August
PanSTARRS (2016 R2)           11      fade     65 N to 60 N   early evening       2018 September
64P/Swift-Gehrels             12      bright   65 N to 40 S   all night           2018 September
ATLAS (2017 T3)               12      fade     45 S to 85 S   early morning       2018 July
37P/Forbes                    12      fade     65 N to 60 S   morning             2018 August
46P/Wirtanen                  13 ?    bright   45 N to 80 S   best morning        Not yet observed
29P/Schwassmann-Wachmann      13 ?    varies   65 N to 65 S   all night           2018 September
Lemmon (2018 EF9)             13      fade     65 N to  5 N   all night           2018 May
PanSTARRS (2016 N6)           13      fade     Poor elongation                    2018 June
ATLAS (2017 M4)               13.5    steady   65 N to 35 S   evening             2018 July
48P/Johnson                   13.5    steady   40 N to 85 S   all night           2018 August
240P/NEAT                     13.5 ?  fade     Poor elongation                    Not yet observed
ATLAS (2018 L2)               14      bright   25 N to 60S    evening             Not yet observed
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.   Details are normally fully updated at the beginning of each month, but may be updated more frequently for comets brighter than 10th magnitude; the date of the most recent partial update, which may apply to only one object, is given.  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. 21P/Giacobini-Zinner is 7th magnitude, however it is not observable until after midnight and most observers don't get up early!
  2. Gas emission from 2017 S3 seems to be quite eratic, leading to irregular changes in the brightness of the comet.   It is in conjunction.
  3. There is to be a Pro-am observing campaign on 46P/Wirtanen in 2018.  There is a brief observing window for UK observers in September which will be useful for determing the magnitude parameters at this return, but it is best seen from the southern hemisphere during this period.   It quickly moves into the evening sky in mid November, and could be a naked eye object in December.  It makes a close approach to Earth on 2018 December 16, passing 0.078 au from us.  It could remain within visual range until March 2019.
  4. The comet predictions for 2019 were updated in 2018 August. The preliminary 2020 predictions were posted in 2017 October. 
  5. 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 2018 June Journal included a paper on "The brighter comets of 2012".  Further papers in this series are in press (2013 - 2014) or under review (2015).
  6. 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 August 1) 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 and the focal ratio.  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.


2016 M1

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. 

Longer period ephemerides are given here for planning purposes for comets that may reach naked eye brightness. All are for the UK.  The ephemerides give B1950 and J2000 positions.  Modern star charts use J2000, but older atlases will use B1950.  The predicted magnitudes are extremely uncertain. 

  • None at present

Planning aids and information for forthcoming comets

  • 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.

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 2017 , 2018 [updated 2018 February 1] , 2019 [updated 2018 August 26] and 2020 [created 2017 October 25] are published in the BAA Journal in December each year. This list [Updated 2018 August 16] 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]> 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; 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, 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 @ 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