Objects in your sky: Comets
Below is a list of the brightest few comets that are visible at present.
You are welcome to reproduce the text below for non-profit purposes, providing you credit In-The-Sky.org.
Comet name | Mag | Constellation | Separation from Sun |
Trend |
Absolute magnitude last updated |
Comet name | Mag | Constellation | Separation from Sun |
Trend |
Absolute magnitude last updated |
C/2023 A3 (Tsuchinshan-ATLAS) | 8.6 | Serpens Cauda | 51° | Fading (peak at mag 2.5 on 7 Oct 2024) | 5 Sep 2024 |
333P/LINEAR | 11.5 | Leo | 75° | Brightening (peak at mag 10.4 on 8 Dec 2024) | 2 Jun 2016 |
C/2024 G3 (ATLAS) | 12.1 | Lupus | 22° | Brightening (peak at mag -1.6 on 13 Jan 2025) | 2 Aug 2024 |
C/2024 S1 (ATLAS) | 12.3 | Hydra | 56° | Fading (peak at mag -5.9 on 28 Oct 2024) | 3 Oct 2024 |
37P/Forbes | 12.8 | Sagittarius | 44° | Fading | 2 Oct 2018 |
12P/Pons-Brooks | 12.8 | Lupus | 27° | Fading – in outburst | 3 Oct 2024 |
C/2022 E2 (ATLAS) | 12.8 | Camelopardalis | 129° | Brightening (peak at mag 12.8 on 25 Nov 2024) | 3 Oct 2024 |
13P/Olbers | 13.3 | Ophiuchus | 13° | Fading | 3 Oct 2024 |
154P/Brewington | 13.5 | Leo | 102° | Fading | 8 Feb 2017 |
C/2017 K2 (PANSTARRS) | 14.2 | Orion | 147° | Fading (peak at mag 14.1 on 21 Oct 2024) | 2 Dec 2023 |
48P/Johnson | 14.2 | Sagittarius | 32° | Brightening (peak at mag 13.9 on 27 Mar 2025) | 31 Oct 2018 |
C/2023 C2 (ATLAS) | 14.3 | Sagittarius | 43° | Fading | 5 Sep 2024 |
C/2021 G2 (ATLAS) | 14.3 | Libra | 20° | Brightening (peak at mag 13.8 on 18 Apr 2025) | 4 Apr 2024 |
C/2021 S3 (PANSTARRS) | 14.3 | Cygnus | 86° | Fading | 1 May 2024 |
65P/Gunn | 15.4 | Libra | 6° | Brightening (peak at mag 13.5 on 27 Jun 2025) | 1 Aug 2017 |
32P/ComasSola | 15.5 | Virgo | 42° | Fading | 14 Sep 2017 |
21P/Giacobini-Zinner | 15.6 | Ophiuchus | 27° | Brightening (peak at mag 11.0 on 25 Mar 2025) | 4 Feb 2019 |
C/2020 V2 (ZTF) | 15.8 | Pavo | 65° | Fading | 30 Aug 2023 |
60P/Tsuchinshan | 15.8 | Pisces | 132° | Brightening (peak at mag 15.0 on 17 Jul 2025) | 3 Oct 2020 |
C/2020 K1 (PANSTARRS) | 16.1 | Columba | 107° | Fading | 30 Aug 2023 |
43P/Wolf-Harrington | 16.2 | Aries | 150° | Brightening | 4 Dec 2018 |
47P/Ashbrook-Jackson | 16.3 | Sagittarius | 35° | Brightening | 29 Feb 2012 |
C/2022 L2 (ATLAS) | 16.4 | Antlia | 81° | Brightening | 1 May 2024 |
C/2019 U5 (PANSTARRS) | 16.5 | Puppis | 96° | Fading | 3 Jul 2023 |
69P/Taylor | 16.5 | Sagittarius | 60° | Fading | Unknown |
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.