1,667 days ago
Dominic Ford, Editor
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Comet C/2018 W2 (Africano) is forecast to reach the brightest point in its 2019 apparition on 26 September. At that time, it will lie at a distance of 1.49 AU from the Sun, and at a distance of 0.50 AU from the Earth.
From Cambridge on 26 September it will be visible in the evening sky, becoming accessible around 19:41 (EDT), 24° above your eastern horizon, as dusk fades to darkness. It will then reach its highest point in the sky at 00:28, 63° above your southern horizon. It will continue to be observable until around 05:27, when it sinks below 21° above your western horizon.
The events that comprise the 2019 apparition of C/2018 W2 (Africano) are as follows:
| Date | Event |
| 05 Sep 2019 | Comet C/2018 W2 (Africano) passes perihelion |
| 26 Sep 2019 | Comet C/2018 W2 (Africano) reaches peak brightness |
| 27 Sep 2019 | Comet C/2018 W2 (Africano) passes perigee |
The table below lists the times when C/2018 W2 (Africano) will be visible from Cambridge day-by-day through its apparition:
| Date | Constellation | Comet visibility |
| 05 Sep 2019 | Perseus | Visible from 21:11 until 05:02 Highest at 04:32, 80° above N horizon |
| 07 Sep 2019 | Andromeda | Visible from 20:58 until 05:04 Highest at 04:11, 82° above N horizon |
| 09 Sep 2019 | Andromeda | Visible from 20:45 until 05:06 Highest at 03:50, 83° above N horizon |
| 11 Sep 2019 | Andromeda | Visible from 20:33 until 05:09 Highest at 03:27, 85° above N horizon |
| 13 Sep 2019 | Andromeda | Visible from 20:21 until 05:11 Highest at 03:04, 88° above N horizon |
| 15 Sep 2019 | Andromeda | Visible from 20:09 until 05:14 Highest at 02:40, 89° above S horizon |
| 17 Sep 2019 | Andromeda | Visible from 19:58 until 05:16 Highest at 02:15, 86° above S horizon |
| 19 Sep 2019 | Andromeda | Visible from 19:54 until 05:18 Highest at 01:50, 81° above S horizon |
| 21 Sep 2019 | Andromeda | Visible from 19:50 until 05:21 Highest at 01:25, 77° above S horizon |
| 23 Sep 2019 | Andromeda | Visible from 19:47 until 05:23 Highest at 01:00, 71° above S horizon |
| 25 Sep 2019 | Pegasus | Visible from 19:43 until 05:25 Highest at 00:36, 65° above S horizon |
| 27 Sep 2019 | Pegasus | Visible from 19:39 until 04:56 Highest at 00:13, 59° above S horizon |
| 29 Sep 2019 | Pisces | Visible from 19:36 until 04:07 Highest at 23:46, 53° above S horizon |
| 01 Oct 2019 | Pisces | Visible from 19:32 until 03:22 Highest at 23:25, 47° above S horizon |
| 03 Oct 2019 | Aquarius | Visible from 19:32 until 02:37 Highest at 23:04, 42° above S horizon |
| 05 Oct 2019 | Aquarius | Visible from 19:38 until 01:52 Highest at 22:45, 37° above S horizon |
| 07 Oct 2019 | Aquarius | Visible from 19:47 until 01:06 Highest at 22:27, 33° above S horizon |
| 09 Oct 2019 | Aquarius | Visible from 20:00 until 00:19 Highest at 22:09, 29° above S horizon |
| 11 Oct 2019 | Aquarius | Visible from 20:18 until 23:28 Highest at 21:53, 26° above S horizon |
| 13 Oct 2019 | Piscis Austrinus | Visible from 20:53 until 22:22 Highest at 21:37, 23° above S horizon |
| 15 Oct 2019 | Piscis Austrinus | Not observable |
A more detailed table of C/2018 W2 (Africano)'s position on each night is available here. A diagram of the orbit of C/2018 W2 (Africano) is available here.
Finder chart
The chart below shows the path of C/2018 W2 (Africano) 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.
Comet brightnesses
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.
No estimate for the brightness of comet C/2018 W2 (Africano) is currently available.
The comet's position on 26 September 2019 will be:
| Object | Right Ascension | Declination | Constellation | Magnitude |
| Comet C/2018 W2 (Africano) | 00h03m00s | 16°11'N | Pegasus | 8.9 |
The coordinates are given in J2000.0.
The sky on 26 Sep 2019
| The sky on 26 September 2019 | ||||||||||||||||||||||||||||||||||
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3% 27 days old |
All times shown in EDT.
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Source
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 02 Jan 2024.
Image credit
© Andy Roberts 1997. Pictured comet is C/1995 O1 Hale-Bopp.