British Astronomical Association
&
Society for Popular Astronomy
Comet Section

Latest Discoveries 

Apr 16  Sergei Schmalz reports a Kreutz group comet in real time C2 images
Apr 17  Sergei Schmalz reports a Kreutz group comet in real time C2 images
Apr 17  PanSTARRS discovers faint comet 2012 G1
Apr 18  Sergei Schmalz reports a Kreutz group comet in real time C2 images
Apr 19  Sergei Schmalz reports a Kreutz group comet in real time C3 images
Apr 19  67P/Churyumov-Gerasimenko recovered by Richard Miles et al using the Faulkes Telescope
Apr 19  Sergei Schmalz reports a Kreutz group comet in real time C2 images
Apr 20  Sergei Schmalz reports a Kreutz group comet in real time C2 images
Apr 22  Sergei Schmalz reports a Kreutz group comet in real time C3 images
Apr 22  Szymon Liwo, Krzysztof Kida and Rafal Reszelewski report a Kreutz group comet in real time C2 images
Apr 23  Sergei Schmalz reports a Marsden group comet in real time C2 images
Apr 23  Bo Zhou reports a non-group comet in real time C3 images
Apr 27  Masanori Uchina reports a Kreutz group comet in real time C2 images
Apr 28  Sergei Schmalz reports a Kreutz group comet in C2 images
Apr 28  Sergei Schmalz and Szymon Liwo report a Kreutz group comet in real time C2 images
Apr 28  Sergei Schmalz reports a Kreutz group comet in real time C2 images
Apr 28  Bo Zhou reports a non-group comet in real time C3 images
Apr 29  Sergei Schmalz reports a Kreutz group comet in real time C2 images
Apr 30  PanSTARRS discovers faint periodic comet 2012 H1
Apr 30  Zhijian Xu reports a Kreutz group comet in real time C2 images
May 01  Sergei Schmalz and Krzysztof Kida report a Kreutz group comet in real time C2 images
May 01  Zhijian Xu reports a Marsden group comet in real time C2 images
May 02  Rob McNaught discovers comet 2012 H2
May 12  Salil Mulye, Sergei Schmalz, Szymon Liwo report a Kreutz group comet in real time C2 images
May 14  Rob Matson reports a Kreutz group comet in real time C3 images
May 15  The Catalina Sky Survey discovers comet 2012 J1
May 15  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 / Current meteor showers / Links / Meetings / IWCA / IWCA III home page / Publications / Comments and Contacts / Old 2012 News / SPA News / Comet discovery procedure / Weather information / The Comet's Tale / More information

Current comet magnitudes (May 1) and observable region (May 1) 

Comet	                  Magnitude   Trend    Observable     When visible   Last visual observation
Garradd (2009 P1)              8.5    fade     60 N to 40 S   best evening   2012 April
Gibbs (2011 A3)               11 ?    fade     35 N to 85 S   morning        2011 October
LINEAR (2011 F1)              11.5    bright   60 N to 10 S   all night      2012 April
246P/NEAT                     11.5    steady ? 60 N to 50 S   all night      2012 March
78P/Gehrels                   12      fade     Poor elongation               2012 April
21P/Giacobini-Zinner          12      fade     Poor elongation               2011 December
LONEOS (2006 S3)              12      steady   50 N to 75 S   morning        2012 April
Hill (2010 G2)                12.5    fade     Poor elongation               2012 February
29P/Schwassmann-Wachmann      13 ?    varies   50 N to 70 S   evening        2012 April
49P/Arend-Rigaux              13.5    fade     60 N to 30 S   best evening   2011 December
Bruenjes (2012 C2)            13.5    fade     Poor elongation               2012 February
LINEAR (2010 S1)              14 ?    steady   60 N to 15 N   morning        2011 November
PanSTARRS (2011 L4)           14      bright   35 N to 85 S   best morning   2012 March

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.  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. Following a Rosetta comet workshop in London held on April 17 & 18, there are plans for a European Amateur Rosetta Network, with a possible European Comet Workshop held in London prior to the 2013 Astrofest. More details when available. Although thought unlikely at the meeting, Richard Miles et al recovered 67P/Churyumov-Gerasimenko using the Faulkes Telescope on April 19.
  2. Yudish Ramanjooloo, a PhD student at MSSL is studying comet ion tails and would welcome any amateur images that show such tail features. He is studying time evolution, so even those images of lower quality may be of use. Contact Yudish at yr2 [at] mssl.ucl.ac.uk if you can help.
  3. 2009 P1 (Garradd) is still visible with binoculars from suburban locations, however it is fading and becoming more diffuse.
  4. 29P/Schwassmann-Wachmann is having frequent outbursts. It was around 11th magnitude when it emerged from conjunction in November and most recently outburst in February.
  5. RAS Press Release on Space Weathering on 81P/Wild
  6. There will be a joint meeting of the Comet and Asteroid Sections of the BAA on Saturday, October 6 at Milton Keynes
  7. Image of the month: Recovery image of 67P/Churyumov-Gerasimenko taken on 2012 April 19 by Richard Miles et al.

Details

Note that in general only details of currently visible comets are updated and that analyses of past years will be published in the BAA Journal.

Comet ephemerides (positions) etc

 The following ephemerides for currently observable comets brighter than 12th magnitude, each for two months, use orbital elements courtesy of the CBAT. Observable limits are for the UK unless stated otherwise. All ephemerides give B1950 and J2000 positions. Modern star charts use J2000, but older atlases will use B1950. Ephemerides were updated as indicated (mm/dd) following the comet name. The following longer period ephemerides are given for planning purposes for comets that may reach binocular brightness. All are for the UK. The predicted magnitudes are extremely uncertain.

An explanation of the information in the ephemerides is given here. The following magnitude parameters, last updated 2012 February, are used in the ephemerides, but note that ephemerides are not updated every time the magnitude parameters are.

The following lists [updated 2012 May 1] give the ephemeris details, including the approximate current magnitude and local visibility for all the comets in the CBAT list for the UK, the equator and 40 south. CCD 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.

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. 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. Following a hack at the MPC, MPECs etc are now available at this site

Finder charts

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.

A plot of recent search areas by professional teams looking for NEOS.

Orbits etc

You can generate your own ephemerides and list of orbital elements at the CBAT Minor Planet and Comet Ephemeris Service web page. The MPC also has a list of the last observation for all comets. In addition, the MPC has orbital elements for unusual asteroids, many of which have cometary orbits. The 2009 edition of the CBAT comet catalogue is now available. Full details of the latest orbits are available from Kazuo Kinoshita's Comet Orbit Home Page.

Downloads etc

Download the January 2012 newsletter.

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 2011, 2012 and 2013 which are published in the BAA Journal in December each year [Updated 2011 October 27]. This list [Updated 2011 December 18] gives the period of visibility and maximum brightness for comets that are predicted to be visible within the next couple of 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

 Please send me observations, they will be used in the reports on comets which appear in the BAA Journal. Visual observers can use the BAA visual report form to log observations and the ICQ format is used to archive observations. There is also a visual drawing form. If you would like to submit by email you should use ICQ format if possible. You can also send observations to Guy Hurst of The Astronomer magazine for publication. I have written a program that creates files with data in the ICQ, BAA and TA formats which you can send to me by email. It now runs under Windows and is available as a self extracting zip file. [New version, 2004 February 2] The German comet group also has a computer program that will correctly format observations for the ICQ [2009 December]. Crni Vhr Observatory has launched the Comet Observation Database which allows entry of observations in ICQ format, and plots of light curves. The ICQ format uses special keys to code observation particulars. I would be particularly pleased to receive drawings, as well as photographs and CCD images. If you are submitting images, please use the standard name format for naming your files, for example 2001q4_20040515_shanklin.jpg. Regular contributors include Seiichi Yoshida and the AGEO team, Jose Carvajal, Jose Aguiar, Marco Goiato, Bjorn Granslo, Werner Hasubick, Rolando Ligustri, Martin Mobberley, David Strange, Nick James, Antonio Milani, Maik Mayer, Stuart Rae, James Abbott, Giovanni Sostero, Nicolas Biver, Pepe Manteca, Michael Mattiazzo, Alexander Amorim, Gabriel Oksa, Rafael Ferrando, Heinz Kerner, Willian Souza, Tony Scarmato, Carlos Labordena, Juan Gonzalez, Walter Robledo, John Fletcher 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 mail the comet section director, Jon Shanklin, but please make sure that it is possible to reply to your address. If you need to phone me, my home number is +44 (0)1223 571250 or my work number is +44 (0)1223 221400. The work fax is +44 (0)1223 221279 I can also be contacted at j.shanklin @ bas.ac.uk and snail mail will reach me at British Antarctic Survey, Madingley Road, CAMBRIDGE CB3 0ET, England. For information about my day job I have a web page at BAS.

Published by jds@ast.cam.ac.uk