Comet 46P/Wirtanen passes perihelion

Dominic Ford, Editor
From the Comets feed


Comet 46P/Wirtanen will make its closest approach to the Sun on 1 January, at a distance of 1.05 AU.

From South El Monte on the day of perihelion it will be visible in the evening sky, becoming accessible around 18:00 (PST), 61° above your south-eastern horizon, as dusk fades to darkness. It will then reach its highest point in the sky at 19:26, 69° above your southern horizon. It will continue to be observable until around 00:16, when it sinks below 21° above your western horizon.

The events that comprise the 1969–1970 apparition of 46P/Wirtanen are as follows:

Date Event

The table below lists the times when 46P/Wirtanen will be visible from South El Monte day-by-day through its apparition:

Date Constellation Comet visibility
20 Feb 1997CetusVisible from 18:41 until 19:09
Highest at 18:41, 27° above W horizon
22 Feb 1997PiscesVisible from 18:43 until 19:11
Highest at 18:43, 28° above W horizon
24 Feb 1997PiscesVisible from 18:44 until 19:13
Highest at 18:44, 28° above W horizon
26 Feb 1997PiscesVisible from 18:46 until 19:14
Highest at 18:46, 28° above W horizon
28 Feb 1997PiscesVisible from 18:48 until 19:16
Highest at 18:48, 28° above W horizon
02 Mar 1997PiscesVisible from 18:49 until 19:18
Highest at 18:49, 28° above W horizon
04 Mar 1997PiscesVisible from 18:51 until 19:21
Highest at 18:51, 28° above W horizon
06 Mar 1997PiscesVisible from 18:53 until 19:23
Highest at 18:53, 28° above W horizon
08 Mar 1997PiscesVisible from 18:54 until 19:25
Highest at 18:54, 28° above W horizon
10 Mar 1997AriesVisible from 18:56 until 19:27
Highest at 18:56, 28° above W horizon
12 Mar 1997AriesVisible from 18:57 until 19:30
Highest at 18:57, 29° above W horizon
14 Mar 1997AriesVisible from 18:59 until 19:32
Highest at 18:59, 29° above W horizon
16 Mar 1997AriesVisible from 19:01 until 19:35
Highest at 19:01, 29° above W horizon
18 Mar 1997AriesVisible from 19:02 until 19:38
Highest at 19:02, 29° above W horizon
20 Mar 1997AriesVisible from 19:04 until 19:40
Highest at 19:04, 29° above W horizon
22 Mar 1997AriesVisible from 19:06 until 19:43
Highest at 19:06, 30° above W horizon
24 Mar 1997AriesVisible from 19:07 until 19:46
Highest at 19:07, 30° above W horizon
26 Mar 1997AriesVisible from 19:09 until 19:49
Highest at 19:09, 30° above W horizon
28 Mar 1997AriesVisible from 19:11 until 19:52
Highest at 19:11, 30° above W horizon
30 Mar 1997AriesVisible from 19:12 until 19:55
Highest at 19:12, 31° above W horizon
01 Apr 1997TaurusVisible from 19:14 until 19:58
Highest at 19:14, 31° above W 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.

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 02h20m00s 13°22'N Aries 9.9

The coordinates are given in J2000.0.

The sky on 4 Nov 2025

The sky on 4 November 2025
Sunrise
06:12
Sunset
16:55
Twilight ends
18:21
Twilight begins
04:46


Waxing Gibbous

99%

14 days old

Planets
Rise Culm. Set
Mercury 08:10 13:04 17:57
Venus 04:59 10:37 16:15
Moon 16:16 23:14 06:23
Mars 07:40 12:45 17:49
Jupiter 21:38 04:42 11:46
Saturn 14:48 20:40 02:31
All times shown in PST.

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 04 Nov 2025.

Image credit

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

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