British Astronomical Association
&
Society for Popular Astronomy
Comet Section


Latest Discoveries

Jul 21  Discovery of 2015 O1 (PanSTARRS) announced
Jul 24  Zhijian Xu reports a Kreutz group comet in real time C3 images
Aug 02  Bo Zhou reports a Kreutz group comet in real time C3 images
Aug 03  Masanori Uchina reports a Kreutz group comet in real time C3 images
Aug 04  Worachate Boonplod reports a Meyer group comet in real time C2 images
Aug 10  Recovery of 2007 V2 (P/Hill) as 2015 P1 reported
Aug 10  Michal Biesiada reports a Meyer group comet in real time C2 images
Aug 11  Recovery of 2002 Q1 (P/Van Ness) as 2015 P2 reported
Aug 11  Discovery of 2015 P3 (SWAN) by Michael Mattiazzo reported
Aug 19  Worachate Boonplod reports a Meyer group comet in real time C2 images
Aug 19  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Aug 19  Discovery of 2015 P4 (P/PanSTARRS) reported
Aug 19  Discovery of 2015 Q1 (Scotti) reported
Aug 19  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 2015 News / SPA News / Comet discovery procedure / Weather information / The Comet's Tale / More information

Current comet magnitudes (August 18) and observable region (August 18)

Comet	                  Magnitude   Trend    Observable     When visible        Last visual observation
Catalina (2013 US10)           6.5    bright   10 N to 85 S   all night           2015 August
PanSTARRS (2014 Q1)            9      fade      0 N to 85 S   evening             2015 August
Lovejoy (2014 Q2)             10      fade     60 N to 20 S   all night           2015 August
SWAN (2015 P3)                10.5    fade     30 N to 70 S   evening             2015 August
Jacques (2015 F4)             11      fade     60 N to 30 S   all night           2015 August
19P/Borelly                   11.5 ?  fade     Poor elongation                    Not yet observed
88P/Howell                    11.5    fade     60 N to 55 S   morning             2015 August
MASTER (2015 G2)              12      fade     Poor elongation                    2015 June
22P/Kopff                     12      bright   30 N to 70 S   evening             2015 August
67P/Churyumov-Gerasimenko     12.5    bright   45 N to 15 S   early morning       2015 August
Spacewatch (2011 KP36)        12.5 ?  steady   55 N to 60 S   best evening        Not yet observed
29P/Schwassmann-Wachmann      13 ?    varies   30 N to 85 S   best evening        2015 August
PanSTARRS (2012 F3)           13.5 ?  fade     45 N to 70 S   best evening        2014 May
PanSTARRS (2012 K1)           13.5 ?  fade     35 N to 85 S   best morning        2015 January
10P/Tempel                    14 ?    bright   45 N to 75 S   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 updated at the beginning and middle of each month, but may be updated more frequently for bright comets.  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. Read the Cometary Science Newsletter
  2. 2013 US10 continues to brighten, but remains a southern hemisphere object.  The light curve based on electronic and visual observations currently indicates a peak aperture corrected magnitude of around 5.   UK observers won't get to see the comet until after perihelion in 2015 November.   
  3. A European Comet Meeting was held in Ondrejov, near Prague, Czech Republic from June 6 -7.  Jakub Cerny has written notes from the meeting..
  4. Do sign up to the Rosetta amateur campaign.  See also the information provided under Rosetta.
  5. 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 and submit them in this format.  Do check the observation files (updated August 18) to see if what you sent matches what is there, as I still have to edit some of the submitted records, particularly the positioning of the DC, which should go in column 56, and the position of "m" when tail length is given in minutes.  If your observations are missing it may be because you have not used the correct format, which includes ICQ as a key.
  6. Selected recent images are displayed in the BAA Comet Gallery.  The full BAA Comet Section image archive is updated whenever images are sent to <cometobs [at] britastro.org> or are received by Denis Buczynski <buczynski8166 [at] btinternet.com>  
  7. Roger Dymock continues to develop his Project Alcock website, with updates posted regularly.  Observers submitting images are encouraged to reduce their images and provide the data in ICQ format for use in analysis.  Nick James has hopes of producing simplified software that will make the reduction easier.
  8. The Planetary Science Institute have a facility for enhancing coma images
  9. Jon's Blog [Updated November 14]

Details


Comet ephemerides (positions) etc

The following ephemerides for currently observable comets brighter than 11th 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. 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.

Planning aids and information for forthcoming comets

  • Rosetta
  • 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]

An explanation of the information in the ephemerides is given here. The following magnitude parameters, last updated 2015 August 18, are used in the ephemerides, but note that ephemerides are not updated every time the magnitude parameters are.

The following lists [updated 2015 August 2] 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.  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. Following a hack at the MPC, MPECs etc are now available at this site

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.

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 available. Full details of the latest orbits are available from Kazuo Kinoshita's Comet Orbit Home Page.  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 and individual computers.

Downloads etc

Download the January 2015 newsletter, which has a report of an RAS meeting, an article on Rosetta, plus the usual reviews and forecasts.  

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 2014 , 2015 and 2016 are published in the BAA Journal in December each year [2016 updated 2015 April 1]. This list [Updated 2015 April 1] 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

Observations may  be used in the reports on comets which appear on these pages, in The Comet's Tale and in the BAA Journal.

Images should be sent to Denis Buczynski at <cometobs [at] britastro.org> or to his personal email at <buczynski8166 [at] btinternet.com>.  We would be particularly pleased to receive drawings, as well as CCD images and photographs.  If you are submitting images, please use the standard name format for naming your files, for example 2001q4_20040515_shanklin.jpg. 

Visual 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 is now standardised as the one to use for submission and archiving of observations, however the ICQ have not updated their observation keys since 2010.  These additional keys are suggested for use when submitting observations to the BAA (updated 2015 February 1).  Observations will continue to be published by Guy Hurst in The Astronomer magazine in TA format. There is also a visual drawing form.   I have written a data entry program that creates a file with data in the ICQ format 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]. I have also written a program to convert from ICQ to TA format. 

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. 

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, Kevin Hills, Nick James, Werner Hasubick, Heinz Kerner, Carlos Labordena, Rolando Ligustri, Michael Mattiazzo, Maik Mayer, Antonio Milani, Martin Mobberley, Gabriel Oksa, Mieczyslaw  Paradowski, Stuart Rae, Walter Robledo, Tony Scarmato, Willian Souza, David Strange 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 comet section director, 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