© Andy Roberts 1997. Pictured comet is C/1995 O1 Hale-Bopp.

46P/Wirtanen at perihelion

Dominic Ford, Editor
From the Comets feed

Please wait
Loading 0/4
Click and drag to rotate
Mouse wheel to zoom in/out
Touch with mouse to dismiss
The sky at

Comet 46P/Wirtanen will make its closest approach to the Sun, at a distance of 1.05 AU.

From Ashburn the 2018–2019 apparition of 46P/Wirtanen will progress as follows:

Begin typing the name of a town near to you, and then select the town from the list of options which appear below.
12 Dec 2018 – 46P/Wirtanen at perihelion
15 Dec 2018 – 46P/Wirtanen reaches its brightest
15 Dec 2018 – 46P/Wirtanen at perigee
21 Nov 2018FornaxVisible from 20:46 until 00:35
Highest at 22:41, 21° above S horizon
23 Nov 2018FornaxVisible from 20:25 until 00:50
Highest at 22:37, 23° above S horizon
25 Nov 2018FornaxVisible from 20:06 until 01:06
Highest at 22:36, 24° above S horizon
27 Nov 2018FornaxVisible from 19:43 until 01:20
Highest at 22:32, 26° above S horizon
29 Nov 2018EridanusVisible from 19:26 until 01:41
Highest at 22:33, 29° above S horizon
01 Dec 2018EridanusVisible from 19:06 until 02:01
Highest at 22:34, 32° above S horizon
03 Dec 2018EridanusVisible from 18:44 until 02:21
Highest at 22:33, 36° above S horizon
05 Dec 2018EridanusVisible from 18:28 until 02:49
Highest at 22:39, 40° above S horizon
07 Dec 2018EridanusVisible from 18:10 until 03:19
Highest at 22:45, 46° above S horizon
09 Dec 2018TaurusVisible from 17:51 until 03:50
Highest at 22:51, 52° above S horizon
11 Dec 2018TaurusVisible from 17:32 until 04:23
Highest at 22:57, 60° above S horizon
13 Dec 2018TaurusVisible from 17:32 until 05:02
Highest at 23:10, 68° above S horizon
15 Dec 2018TaurusVisible from 17:30 until 05:46
Highest at 23:27, 76° above S horizon
17 Dec 2018AurigaVisible from 17:32 until 06:28
Highest at 23:42, 84° above S horizon
19 Dec 2018AurigaVisible from 17:37 until 06:37
Highest at 00:08, 89° above N horizon
21 Dec 2018AurigaVisible from 17:39 until 06:39
Highest at 00:29, 84° above N horizon
23 Dec 2018AurigaVisible from 17:41 until 06:37
Highest at 00:46, 80° above N horizon
25 Dec 2018LynxVisible from 17:47 until 06:35
Highest at 01:09, 77° above N horizon
27 Dec 2018LynxVisible from 17:52 until 06:32
Highest at 01:24, 74° above N horizon
29 Dec 2018LynxVisible from 17:54 until 06:30
Highest at 01:42, 73° above N horizon
31 Dec 2018LynxVisible from 18:00 until 06:28
Highest at 01:54, 72° above N horizon

A more detailed table of 46P/Wirtanen's position on each night is available here. A diagram of the orbit of 46P/Wirtanen is available here.

At the moment of perihelion it will be visible in the evening sky, becoming accessible around 17:55 (EST), 19° above your eastern horizon, as dusk fades to darkness. It will then reach its highest point in the sky at 22:47, 60° above your southern horizon. It will continue to be observable until around 03:53, when it sinks below 16° above your western horizon.

Finder chart

The chart below shows the path of 46P/Wirtanen 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 46P/Wirtanen is currently available.

The comet's position at perihelion will be:

Object Right Ascension Declination Constellation Magnitude
Comet 46P/Wirtanen 04h01m30s 9°37'N Taurus 3.2

The coordinates are given in J2000.0.

The sky on 12 December 2018
Twilight ends
Twilight begins

5-day old moon
Waxing Crescent


5 days old

Rise Culm. Set
Mercury 05:35 10:38 15:42
Venus 03:40 09:06 14:32
Moon 11:13 16:28 21:46
Mars 12:13 17:57 23:41
Jupiter 06:17 11:09 16:00
Saturn 08:40 13:24 18:09
All times shown in EST.


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 27 Jul 2021.

Image credit

© Andy Roberts 1997. Pictured comet is C/1995 O1 Hale-Bopp.






Color scheme