British Astronomical Association

Comet Section

Director: Nick James

Visual observations page


(Co-ordinator Jonathan Shanklin)

Latest Discoveries

Feb 25  Zhijian Xu reports a Kreutz group comet in real time C3 images
Feb 27  Zhijian Xu reports a Kreutz group comet in real time C3 images
Mar 01  Discovery of 2017 D1 (P/Fuls) reported
Mar 01  Discovery of 2017 D2 (Barros) reported
Mar 01  Discovery of 2017 D3 (ATLAS) reported
Mar 01  Discovery of 2017 D4 (P/PanSTARRS) reported
Mar 01  Masanori Uchina reports a Meyer group comet in real time C2 images
Mar 02  Masanori Uchina reports a Kreutz group comet in real time C3 images
Mar 02  Michal Biesiada reports a Kreutz group comet in real time C3 images
Mar 04  Discovery of 2017 E1 (Borisov) reported
Mar 04  Szymon Liwo reports a Kreutz group comet in real time C3 images
Mar 07  Discovery of 2017 E2 (XuYi) reported
Mar 12  Worachate Boonplod and Michal Biesiada report a Kreutz group comet in real time C3 images
Mar 13  Discovery of 2017 E3 (PanSTARRS) reported
Mar 13  Discovery of 2017 E4 (Lovejoy) reported
Mar 14  Worachate Boonplod reports two Kreutz group comets in real time C3 images
Mar 21  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 2017 News / Comet discovery procedure / Weather information / The Comet's Tale / BAA Comet Section image archive / Project Alcock / More information / Legacy page

Current comet magnitudes (March 21) and observable region (March 21)

Comet	                  Magnitude   Trend    Observable     When visible        Last visual observation
2P/Encke                       6.5    fade      0 N to 70 S   early morning       2017 February
41P/Tuttle-Giacobinni-Kresak   8.5    bright   80 N to 45 S   best evening        2017 March
PanSTARRS (2015 ER61)          9      bright   50 N to 75 S   early morning       2017 March
Lovejoy (2017 E4)              9      bright   45 N to 75 S   morning             2017 March
Johnson (2015 V2)              9.5    bright   80 N to 30 S   best morning        2017 March
45P/Honda-Mrkos-Pajdusakova   10      fade     80 N to 45 S   best morning        2017 March
73P/Schwassmann-Wachmann      11      bright   10 N to 50 S   early morning       2017 February
PanSTARRS (2016 VZ18)         11      steady   80 N to 15 S   evening             2017 March
Borisov (2017 E1)             12      steady   35 N to 50 S   early morning       2017 March
315P/LONEOS                   12.5    o'burst? 70 N to  5 S   all night           2017 March
PanSTARRS (2016 R2)           13 ?    bright   15 N to 55 S   evening             Not yet observed
29P/Schwassmann-Wachmann      13 ?    varies   Poor elongation                    2016 November
237P/LINEAR                   14      fade     In conjunction                     2016 November
Spacewatch (2011 KP36)        14      fade     Poor elongation                    2016 November
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 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. 2017 E4 is much brighter than had been expected from the initial CCD observations.  It could brighten another magnitude or more, but will remain a morning object.
  2. 41P is visible in large binoculars and will brighten a little more as it approaches its close (0.14 au) pass to the Earth on April 1.  It is well placed for observation for UK observers.
  3. 2015 ER61 is brightening and it should be in range of large binoculars.  The light curve remains a little uncertain, however the comet could reach 6th magnitude (2 magnitudes) around the time of perihelion in 2017 May.  It is a morning object when at its best and doesn't get into the evening sky until it is fading in 2017 August.
  4. 2015 V2 is currently brightening slowly, with electronic VEM observations rather fainter than the visual ones.  It could reach binocular visibility this month and might reach 6th magnitude.  It will become visible in the late evening, but is highest in the morning skies.
  5. 45P/Honda-Mrkos-Pajdusakova seems to have retained a faint outer coma and is brighter than indicated by the mean light-curve.
  6. The comet predictions for 2019 were published in early January.
  7. 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 February Journal includes a paper on "The brighter comets of 2009".  Further papers in this series are in press or in draft.
  8. 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 March 2) 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, 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.

Details

2p.jpg (298432 bytes)41p.jpg (241852 bytes)15erobs.jpg (308854 bytes)15v2obs.jpg (308631 bytes)


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.  It is currently unlikely that either comet will be bright.

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 2016 , 2017 [updated 2017 January 1] , 2018 [updated 2017 January 1] and 2019 [new 2017 January 7] are published in the BAA Journal in December each year. This list [Updated 2017 January 7] 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.

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; 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, Kevin Hills, Nick James, Werner Hasubick, 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 and Seiichi Yoshida, several of whom contribute observations from their colleagues.

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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