Objects in your sky: Comets
Below is a list of the brightest few comets that are visible at present.
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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/2017 K2 (PANSTARRS) | 9.7 | Ophiuchus | 130° | Brightening | 1 May 2022 |
22P/Kopff | 10.7 | Pisces | 65° | Fading (peak at mag 10.3 on 1 Apr 2022) | 1 Apr 2018 |
C/2021 E3 (ZTF) | 10.7 | Indus | 104° | Brightening (peak at mag 10.5 on 2 Jun 2022) | 1 May 2022 |
45P/Honda-Mrkos-Pajdusakova | 10.8 | Taurus | 25° | Fading (peak at mag 8.8 on 28 Apr 2022) | 4 Dec 2018 |
C/2019 L3 (ATLAS) | 11.0 | Canis Minor | 50° | Fading | 1 May 2022 |
C/2021 O3 (PANSTARRS) | 11.6 | Camelopardalis | 60° | Fading (peak at mag 8.0 on 24 Apr 2022) | 2 Apr 2022 |
9P/Tempel | 11.6 | Aquarius | 91° | Fading | 4 Dec 2018 |
C/2021 P4 (ATLAS) | 11.7 | Camelopardalis | 40° | Brightening (peak at mag 9.2 on 29 Jul 2022) | 1 May 2022 |
116P/Wild | 11.9 | Leo | 86° | Fading | 4 Dec 2018 |
19P/Borrelly | 12.0 | Lynx | 50° | Fading | 1 Apr 2018 |
C/2019 T4 (ATLAS) | 12.1 | Crater | 118° | Fading (peak at mag 12.0 on 9 Apr 2022) | 1 May 2022 |
C/2021 F1 (Lemmon-PANSTARRS) | 12.2 | Cetus | 27° | Fading (peak at mag 8.7 on 4 Apr 2022) | 2 Apr 2022 |
117P/Helin-Roman-Alu | 13.0 | Sagittarius | 135° | Brightening (peak at mag 12.8 on 1 Jul 2022) | 16 Oct 2014 |
C/2020 V2 | 13.6 | Ursa Major | 73° | Brightening | 1 May 2022 |
67P/Churyumov-Gerasimenko | 13.7 | Leo | 81° | Fading | 1 Apr 2018 |
110P/Hartley | 13.7 | Cancer | 71° | Fading | 29 Feb 2012 |
8P/Tuttle | 13.8 | Ara | 143° | Fading | 3 Jan 2022 |
C/2021 A1 (Leonard) | 13.9 | Corona Australis | 137° | Fading | 4 Feb 2022 |
104P/Kowal | 13.9 | Leo | 78° | Fading | 4 Dec 2018 |
73P/Schwassmann-Wachmann | 14.0 | Leo | 80° | Brightening (peak at mag 11.0 on 4 Sep 2022) | 4 Apr 2017 |
C/2019 U5 (PANSTARRS) | 14.0 | Bootes | 114° | Brightening | 1 May 2022 |
81P/Wild | 14.1 | Taurus | 18° | Brightening (peak at mag 10.4 on 14 Jan 2023) | 4 Dec 2018 |
C/2020 K1 (PANSTARRS) | 14.3 | Hercules | 122° | Brightening | 1 May 2022 |
4P/Faye | 14.7 | Cancer | 60° | Fading | 14 Sep 2017 |
52P/Harrington-Abell | 14.8 | Virgo | 122° | 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.