Objects in your sky: Comets
2P/Encke
1980 Nov 08 perihelion[chart]
1984 Feb 28 perihelion[chart]
1987 Jun 19 perihelion[chart]
1990 Oct 07 perihelion[chart]
1994 Jan 26 perihelion[chart]
1997 May 17 perihelion[chart]
2000 Sep 05 perihelion[chart]
2003 Dec 25 perihelion[chart]
2007 Apr 15 perihelion[chart]
2010 Aug 04 perihelion[chart]
2013 Nov 23 perihelion[chart]
2017 Mar 14 perihelion[chart]
2020 Jul 02 perihelion[chart]
2023 Oct 22 perihelion[chart]
2027 Feb 10 perihelion[chart]
8P/Tuttle
1980 Oct 12 perihelion[chart]
1994 May 29 perihelion[chart]
2008 Jan 12 perihelion[chart]
2021 Aug 28 perihelion[chart]
10P/Tempel
1983 Sep 10 perihelion[chart]
1994 Jun 01 perihelion[chart]
1999 Oct 11 perihelion[chart]
2010 Jul 02 perihelion[chart]
2021 Mar 22 perihelion[chart]
2026 Aug 02 perihelion[chart]
15P/Finlay
1982 Jan 25 perihelion[chart]
1988 Aug 23 perihelion[chart]
1995 Mar 22 perihelion[chart]
2001 Oct 19 perihelion[chart]
2008 May 17 perihelion[chart]
2014 Dec 14 perihelion[chart]
2021 Jul 13 perihelion[chart]
2028 Feb 09 perihelion[chart]
19P/Borrelly
1980 Dec 19 perihelion[chart]
1987 Oct 27 perihelion[chart]
2022 Feb 02 perihelion[chart]
2028 Dec 10 perihelion[chart]
21P/Giacobini-Zinner
1992 Aug 07 perihelion[chart]
2005 Aug 26 perihelion[chart]
2018 Sep 14 perihelion[chart]
2025 Mar 25 perihelion[chart]
22P/Kopff
1990 Jul 15 perihelion[chart]
2009 Jul 17 perihelion[chart]
2022 Mar 19 perihelion[chart]
2028 Jul 19 perihelion[chart]
26P/Grigg-Skjellerup
1987 May 02 perihelion[chart]
2008 Apr 10 perihelion[chart]
2029 Mar 20 perihelion[chart]
45P/Honda-Mrkos-Pajdusakova
1984 Nov 28 perihelion[chart]
1990 Apr 03 perihelion[chart]
1995 Aug 07 perihelion[chart]
2000 Dec 10 perihelion[chart]
2006 Apr 15 perihelion[chart]
2011 Aug 19 perihelion[chart]
2016 Dec 22 perihelion[chart]
2022 Apr 27 perihelion[chart]
2027 Aug 31 perihelion[chart]
46P/Wirtanen
1980 Nov 23 perihelion[chart]
1991 Oct 08 perihelion[chart]
1997 Mar 15 perihelion[chart]
2008 Jan 28 perihelion[chart]
2018 Dec 11 perihelion[chart]
2024 May 19 perihelion[chart]
2029 Oct 25 perihelion[chart]
58P/Jackson-Neujmin
1995 Aug 02 perihelion[chart]
2003 Nov 09 perihelion[chart]
2020 May 27 perihelion[chart]
2028 Sep 04 perihelion[chart]
67P/Churyumov-Gerasimenko
2008 Dec 22 perihelion[chart]
2021 Nov 02 perihelion[chart]
2028 Apr 08 perihelion[chart]
71P/Clark
1989 May 03 perihelion[chart]
2000 Jul 30 perihelion[chart]
2017 Jun 10 perihelion[chart]
2023 Jan 23 perihelion[chart]
2028 Sep 06 perihelion[chart]
73P/Schwassmann-Wachmann
1990 Jul 31 perihelion[chart]
2006 Aug 17 perihelion[chart]
2017 Apr 29 perihelion[chart]
2022 Sep 04 perihelion[chart]
2028 Jan 10 perihelion[chart]
81P/Wild
1997 Apr 20 perihelion[chart]
2010 Feb 16 perihelion[chart]
2022 Dec 15 perihelion[chart]
2029 May 15 perihelion[chart]
88P/Howell
1982 May 19 perihelion[chart]
1987 Nov 10 perihelion[chart]
1993 May 03 perihelion[chart]
1998 Oct 25 perihelion[chart]
2004 Apr 17 perihelion[chart]
2009 Oct 10 perihelion[chart]
2015 Apr 03 perihelion[chart]
2020 Sep 24 perihelion[chart]
2026 Mar 18 perihelion[chart]
96P/Machholz
1980 Nov 12 perihelion[chart]
1986 Feb 22 perihelion[chart]
1991 Jun 03 perihelion[chart]
1996 Sep 12 perihelion[chart]
2001 Dec 22 perihelion[chart]
2007 Apr 02 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 18 perihelion[chart]
1999 Jan 15 perihelion[chart]
2004 Oct 15 perihelion[chart]
2022 Jan 12 perihelion[chart]
2027 Oct 12 perihelion[chart]
141P/Machholz
1988 Nov 20 perihelion[chart]
2004 Dec 04 perihelion[chart]
2020 Dec 17 perihelion[chart]
2026 Apr 22 perihelion[chart]
154P/Brewington
1992 Dec 02 perihelion[chart]
2013 Dec 09 perihelion[chart]
2024 Jun 13 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.