Objects in your sky: Comets
2P/Encke
1980 Nov 04 perihelion[chart]
1984 Feb 24 perihelion[chart]
1987 Jun 15 perihelion[chart]
1990 Oct 04 perihelion[chart]
1994 Jan 23 perihelion[chart]
1997 May 15 perihelion[chart]
2000 Sep 03 perihelion[chart]
2003 Dec 24 perihelion[chart]
2007 Apr 14 perihelion[chart]
2010 Aug 03 perihelion[chart]
2013 Nov 22 perihelion[chart]
2017 Mar 13 perihelion[chart]
2020 Jul 02 perihelion[chart]
2023 Oct 22 perihelion[chart]
2027 Feb 10 perihelion[chart]
8P/Tuttle
1980 Oct 16 perihelion[chart]
1994 May 31 perihelion[chart]
2008 Jan 13 perihelion[chart]
2021 Aug 27 perihelion[chart]
10P/Tempel
1983 Sep 17 perihelion[chart]
1994 Jun 06 perihelion[chart]
2010 Jul 04 perihelion[chart]
2021 Mar 23 perihelion[chart]
2026 Aug 02 perihelion[chart]
15P/Finlay
1982 Jan 31 perihelion[chart]
1988 Aug 28 perihelion[chart]
1995 Mar 27 perihelion[chart]
2001 Oct 22 perihelion[chart]
2008 May 19 perihelion[chart]
2014 Dec 16 perihelion[chart]
2021 Jul 13 perihelion[chart]
2028 Feb 08 perihelion[chart]
19P/Borrelly
1980 Dec 24 perihelion[chart]
1987 Oct 31 perihelion[chart]
2022 Feb 01 perihelion[chart]
2028 Dec 09 perihelion[chart]
21P/Giacobini-Zinner
1992 Jul 30 perihelion[chart]
2005 Aug 21 perihelion[chart]
2018 Sep 13 perihelion[chart]
2025 Mar 25 perihelion[chart]
22P/Kopff
1990 May 24 perihelion[chart]
2009 Jun 26 perihelion[chart]
2022 Mar 18 perihelion[chart]
2028 Jul 28 perihelion[chart]
45P/Honda-Mrkos-Pajdusakova
1984 Nov 30 perihelion[chart]
1990 Apr 05 perihelion[chart]
1995 Aug 09 perihelion[chart]
2000 Dec 11 perihelion[chart]
2006 Apr 16 perihelion[chart]
2011 Aug 19 perihelion[chart]
2016 Dec 22 perihelion[chart]
2022 Apr 27 perihelion[chart]
2027 Aug 30 perihelion[chart]
46P/Wirtanen
1980 Nov 21 perihelion[chart]
1991 Oct 06 perihelion[chart]
1997 Mar 14 perihelion[chart]
2008 Jan 27 perihelion[chart]
2018 Dec 11 perihelion[chart]
2024 May 19 perihelion[chart]
2029 Oct 25 perihelion[chart]
58P/Jackson-Neujmin
1995 Aug 06 perihelion[chart]
2003 Nov 13 perihelion[chart]
2020 May 27 perihelion[chart]
2028 Sep 02 perihelion[chart]
67P/Churyumov-Gerasimenko
2008 Dec 23 perihelion[chart]
2021 Nov 02 perihelion[chart]
2028 Apr 07 perihelion[chart]
71P/Clark
2006 May 10 perihelion[chart]
2017 Jun 29 perihelion[chart]
2023 Jan 22 perihelion[chart]
2028 Aug 17 perihelion[chart]
73P/Schwassmann-Wachmann
1995 Jun 25 perihelion[chart]
2006 May 07 perihelion[chart]
2022 Aug 26 perihelion[chart]
2028 Feb 01 perihelion[chart]
81P/Wild
1997 Apr 15 perihelion[chart]
2010 Feb 14 perihelion[chart]
2022 Dec 15 perihelion[chart]
2029 May 16 perihelion[chart]
88P/Howell
1982 May 26 perihelion[chart]
1987 Nov 16 perihelion[chart]
1993 May 08 perihelion[chart]
1998 Oct 30 perihelion[chart]
2004 Apr 21 perihelion[chart]
2009 Oct 12 perihelion[chart]
2015 Apr 05 perihelion[chart]
2020 Sep 25 perihelion[chart]
2026 Mar 18 perihelion[chart]
96P/Machholz
1980 Nov 14 perihelion[chart]
1986 Feb 24 perihelion[chart]
1991 Jun 05 perihelion[chart]
1996 Sep 13 perihelion[chart]
2001 Dec 23 perihelion[chart]
2007 Apr 03 perihelion[chart]
2012 Jul 12 perihelion[chart]
2017 Oct 21 perihelion[chart]
2023 Jan 31 perihelion[chart]
2028 May 11 perihelion[chart]
104P/Kowal
1981 Oct 19 perihelion[chart]
1999 Jan 15 perihelion[chart]
2004 Oct 15 perihelion[chart]
2022 Jan 11 perihelion[chart]
2027 Oct 12 perihelion[chart]
141P/Machholz
1988 Nov 18 perihelion[chart]
2004 Dec 02 perihelion[chart]
2020 Dec 17 perihelion[chart]
2026 Apr 22 perihelion[chart]
154P/Brewington
1992 Dec 10 perihelion[chart]
2013 Dec 10 perihelion[chart]
2024 Jun 11 perihelion[chart]
The position of each comet is calculated from orbital elements published by the Minor Planet Center (MPC).
The brightnesses of comets are estimated from magnitude parameters published by the BAA Comet Section, where these are available. These are computed from the observations they receive from amateur astronomers.
Comets are intrinsically highly unpredictable objects, since their brightness depends on the scattering of sunlight from dust particles in the comet's coma and tail. This dust is continually streaming away from the comet's nucleus, and its density at any particular time is governed by the rate of sublimation of the ice in the comet's nucleus, as it is heated by the Sun's rays. It also depends on the amount of dust that is mixed in with that ice. This is very difficult to predict in advance, and can be highly variable even between successive apparitions of the same comet.
In consequence, while the future positions of comets are usually known with a high degree of confidence, their future brightnesses are not. For most comets, we do not publish any magnitude estimates at all. For the few comets where we do make estimates, we generally prefer the BAA's magnitude parameters to those published by the Minor Planet Center, since they are typically updated more often.