Objects in your sky: Comets

by Dominic Ford


2018 Nov 12 perihelion[chart]


1998 Feb 01 perihelion[chart]


2026 Nov 28 perihelion[chart]

C/1995 O1 (Hale-Bopp)

1997 Mar 30 perihelion[chart]

C/2009 G1 (STEREO)

2009 Apr 18 perihelion[chart]


2022 Dec 19 perihelion[chart]


2020 May 05 perihelion[chart]

C/2018 L2 (ATLAS)

2018 Dec 01 perihelion[chart]

C/2018 N2 (ASASSN)

2019 Nov 11 perihelion[chart]

C/2018 R3 (Lemmon)

2019 Jun 08 perihelion[chart]

C/2018 V1 (Machholz-Fujikawa-Iwamoto)

2018 Dec 03 perihelion[chart]

C/2018 W1 (Catalina)

2019 May 12 perihelion[chart]

C/2018 W2 (Africano)

2019 Sep 05 perihelion[chart]

C/2018 Y1 (Iwamoto)

2019 Feb 04 perihelion[chart]

C/2019 L3 (ATLAS)

2022 Jan 09 perihelion[chart]

C/2019 N1 (ATLAS)

2020 Nov 30 perihelion[chart]

C/2019 U6 (Lemmon)

2020 Jun 18 perihelion[chart]

C/2020 F3 (NEOWISE)

2020 Jul 04 perihelion[chart]

C/2020 K8 (Catalina-ATLAS)

2020 Sep 15 perihelion[chart]

C/2020 M3 (ATLAS)

2020 Oct 25 perihelion[chart]

C/2020 P1 (NEOWISE)

2020 Oct 20 perihelion[chart]

C/2020 Q1 (Borisov)

2020 Aug 14 perihelion[chart]

C/2020 R4 (ATLAS)

2021 Mar 02 perihelion[chart]

C/2020 S3 (Erasmus)

2020 Dec 11 perihelion[chart]

C/2020 T2 (Palomar)

2021 Jul 10 perihelion[chart]

C/2021 A1 (Leonard)

2022 Jan 03 perihelion[chart]

C/2021 A2 (NEOWISE)

2021 Jan 22 perihelion[chart]

C/2021 D1 (SWAN)

2021 Feb 27 perihelion[chart]

C/2021 F1 (Lemmon-PANSTARRS)

2022 Apr 06 perihelion[chart]

C/2021 P4 (ATLAS)

2022 Jul 30 perihelion[chart]


2024 Feb 14 perihelion[chart]

C/2021 T4 (Lemmon)

2023 Jul 31 perihelion[chart]


2023 Feb 18 perihelion[chart]

C/2022 P1 (NEOWISE)

2022 Nov 28 perihelion[chart]

C/2022 U2 (ATLAS)

2023 Jan 14 perihelion[chart]

C/2023 A3 (Tsuchinshan-ATLAS)

2024 Sep 27 perihelion[chart]

C/2023 E1 (ATLAS)

2023 Jul 01 perihelion[chart]

C/2023 H2 (Lemmon)

2023 Oct 29 perihelion[chart]

C/2023 P1 (Nishimura)

2023 Sep 17 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.





Color scheme