71 days ago
Dominic Ford, Editor
From the Comets feed
Comet C/2022 U2 (ATLAS) will make its closest approach to the Sun on 14 January, at a distance of 1.33 AU.
From San Diego on the day of perihelion it will be visible all night because it is circumpolar. It will be highest in the sky at dusk, becoming accessible around 18:05 (PDT), 47° above your northern horizon. It will be lost to dawn twilight around 05:46, 18° above your northern horizon.
The events that comprise the 2022–2023 apparition of C/2022 U2 (ATLAS) are as follows:
|14 Jan 2023||Comet C/2022 U2 (ATLAS) passes perihelion|
The table below lists the times when C/2022 U2 (ATLAS) will be visible from San Diego day-by-day through its apparition:
|24 Dec 2022||Draco||Visible from 17:51 until 05:42|
Highest at 17:51, 40° above N horizon
|26 Dec 2022||Draco||Visible from 17:52 until 05:43|
Highest at 17:52, 40° above N horizon
|28 Dec 2022||Cepheus||Visible from 17:53 until 05:44|
Highest at 17:53, 40° above N horizon
|30 Dec 2022||Cepheus||Visible from 17:54 until 05:45|
Highest at 17:54, 40° above N horizon
|01 Jan 2023||Cepheus||Visible from 17:56 until 05:45|
Highest at 17:56, 41° above N horizon
|03 Jan 2023||Cepheus||Visible from 17:57 until 05:46|
Highest at 17:57, 41° above N horizon
|05 Jan 2023||Cepheus||Visible from 17:58 until 05:46|
Highest at 17:58, 42° above N horizon
|07 Jan 2023||Cepheus||Visible from 18:00 until 05:46|
Highest at 18:00, 43° above N horizon
|09 Jan 2023||Cepheus||Visible from 18:01 until 05:46|
Highest at 18:01, 44° above N horizon
|11 Jan 2023||Cassiopeia||Visible from 18:03 until 05:47|
Highest at 18:03, 45° above N horizon
|13 Jan 2023||Cassiopeia||Visible from 18:05 until 05:46|
Highest at 18:05, 47° above N horizon
|15 Jan 2023||Cassiopeia||Visible from 18:06 until 05:46|
Highest at 18:08, 48° above N horizon
|17 Jan 2023||Cassiopeia||Visible from 18:08 until 05:46|
Highest at 18:32, 50° above N horizon
|19 Jan 2023||Cassiopeia||Visible from 18:10 until 05:46|
Highest at 18:52, 53° above N horizon
|21 Jan 2023||Camelopardalis||Visible from 18:11 until 02:39|
Highest at 19:07, 55° above N horizon
|23 Jan 2023||Camelopardalis||Visible from 18:13 until 02:33|
Highest at 19:18, 58° above N horizon
|25 Jan 2023||Camelopardalis||Visible from 18:15 until 02:26|
Highest at 19:27, 61° above N horizon
|27 Jan 2023||Camelopardalis||Visible from 18:16 until 02:19|
Highest at 19:33, 64° above N horizon
|29 Jan 2023||Camelopardalis||Visible from 18:18 until 02:11|
Highest at 19:37, 67° above N horizon
|31 Jan 2023||Perseus||Visible from 18:20 until 02:03|
Highest at 19:40, 71° above N horizon
|02 Feb 2023||Perseus||Visible from 18:21 until 01:55|
Highest at 19:42, 74° above N horizon
A more detailed table of C/2022 U2 (ATLAS)'s position on each night is available here. A diagram of the orbit of C/2022 U2 (ATLAS) is available here.
The chart below shows the path of C/2022 U2 (ATLAS) over the course of its apparition, as calculated from the orbital elements published by the Minor Planet Center (MPC). It is available for download, either on dark background, in PNG, PDF or SVG formats, or on a light background, in PNG, PDF or SVG formats. It was produced using StarCharter.
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.
Based on the magnitude parameters published for this comet by the BAA Comet Section, we estimate that it may be around mag 11 on 14 January 2023. This estimate is based on observations that the BAA has received from amateur astronomers, assuming that its current level of activity will remain constant.
You will probably require a telescope to see this comet. It is unlikely to be visible through bird-watching binoculars, and even less likely to be visible to the unaided eye.
The comet's position at perihelion will be:
|Comet C/2022 U2 (ATLAS)||01h33m50s||75°28'N||Cassiopeia||11.2|
The coordinates are given in J2000.0.
The sky on 14 Jan 2023
|The sky on 14 January 2023|
22 days old
All times shown in PST.
This event was automatically generated on the basis of orbital elements published by the Minor Planet Center (MPC) , and is updated whenever new elements become available. It was last updated on 21 Mar 2023.
© Andy Roberts 1997. Pictured comet is C/1995 O1 Hale-Bopp.