British Astronomical Association
&
Society for Popular Astronomy
Comet Section


Latest Discoveries

Jan 25  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Jan 25  Discovery of 2015 A3 (P/PanSTARRS) reported
Jan 26  Worachate Boonplod reports a Meyer group comet in real time C2 images
Jan 28  Richard Miles reports a significant outburst on 17P/Holmes
Jan 31  Zhijian Xu reports a Meyer group comet in real time C2 images
Jan 31  Szymon Liwo reports a Kreutz group comet in real time C3 images
Feb 04  Discovery of 2015 B1 (PanSTARRS) reported
Feb 08  Trygve Prestgard reports a Kreutz group comet in real time C3 images
Feb 09  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Feb 10  Worachate Boonplod reports a Kreutz group comet in real time C3 images
Feb 12  Peiyuan Sun reports a Kreutz group comet in real time C3 images
Feb 13  Discovery of 2015 B2 (PanSTARRS) reported
Feb 14  Szymon Liwo reports a Kreutz group comet in real time C3 images
Feb 17  Discovery of 2015 C1 (P/TOTAS-Gibbs) reported
Feb 18  Masanori Uchina reports a Kreutz group comet in real time C3 images
Feb 18  Worachate Boonplod reports a non-group comet in real time C3 images
Feb 18  Trygve Prestgard reports a Kreutz group comet in real time C3 images
Feb 21  Trygve Prestgard reports a Kreutz group comet in real time C3 images
Feb 22  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 (February 15) and observable region (February 15)

Comet	                  Magnitude   Trend    Observable     When visible        Last visual observation
Lovejoy (2014 Q2)              5      fade     85 N to 20 S   all night           2015 February
88P/Howell                    11      bright   30 N to 60 S   morning             2015 February
15P/Finlay                    11      fade     80 N to 25 S   evening             2015 February
PanSTARRS (2012 K1)           11.5    fade     Poor elongation                    2014 December
Siding Spring (2013 A1)       12      steady   80 N to 20 S   morning             2014 November
Catalina (2013 US10)          12      bright   Conjunction                        2014 November
Borisov (2014 R1)             12.5    fade     45 N to 55 S   morning             2014 November
Oukaimeden (2013 V5)          13      fade     65 N to 45 S   morning             2014 October
29P/Schwassmann-Wachmann      13 ?    varies   20 N to 60 S   morning             2014 October
PanSTARRS (2012 F3)           13.5 ?  steady   30 N to 40 S   early morning       2014 May
32P/Comas Sola                13.5    fade     80 N to 40 S   best morning        2014 November
17P/Holmes                    13.5    fade     85 N to 15 S   best evening        Not yet observed
PanSTARRS (2014 Q1)           15 ?    bright   Poor elongation                    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. Richard Miles reports an outburst on 17P/Holmes.  The comet may be around 14th magnitude visually, with an expanding coma.
  2. 2014 Q2 (Lovejoy) is still an easy object in small binoculars.  The comet is past its brightest, but seems to be holding its brightness.  It looks like a small fuzzy patch of light, about a third the diameter of the moon in size.  It should remain an easy object for another month or two.  The ion tail suffered a disconnection event on January 8.  See the BAA Computing Section online charts for detailed finder maps, though these work better for fainter comets.  
  3. 15P/Finlay appears to have brightened very rapidly at the end of December, and brightened further in mid January, though this was short lived.   The data fits a linear type light curve with the comet brightest some 16 days after perihelion.
  4. The discovery of twelve comets from the ground during the second half of November was a record for a half-month.
  5. Magnitude analyses were updated on February 15, but do not change the following  :   Electronic and visual observations of 2013 US10 currently predict a peak aperture corrected magnitude of around 2.   UK observers won't get to see the comet until after perihelion in 2015 November.   Electronic observations by Kevin Hills suggest that 2014 Q1 has a relatively faint absolute magnitude and its rate of brightening is slowing as it gets closer to perihelion.  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 February 15) 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.  If your observations are missing it may be because you have not used the correct format, which includes ICQ as a key.
  6. Rosetta is orbiting about 67P/Churyumov-Gerasimenko and is taking stunningly detailed images, which show an irregularly shaped nucleus full of varied rock formations.   The unusual shape of the nucleus could help explain the light curve of this and other comets which exhibit linear behaviour.  Philae landed, successfully carried out science observations as planned, and is now in sleep mode.  It may wake up as the comet approaches the Sun.
  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.  
  8. BAA Comet Section image archive This archive is updated whenever images are sent to <cometobs [at] britastro.org> or are received by Denis Buczynski <buczynski8166 [at] btinternet.com>
  9. The Planetary Science Institute have a facility for enhancing coma images
  10. Jon's Blog [Updated November 14]
  11. Image of the month: Sequence of images showing the outburst of 29P/Schwassmann-Wachmann in 2013 June and July taken by Damian Peach.

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

An explanation of the information in the ephemerides is given here. The following magnitude parameters, last updated 2015 February 15, are used in the ephemerides, but note that ephemerides are not updated every time the magnitude parameters are.

The following lists [updated 2015 February 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.  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 2000.  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 [updated 2014 December 2]. This list [Updated 2014 December 2] 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