Comet 168P/Hergenrother passes perihelion

Dominic Ford, Editor
From the Comets feed


Comet 168P/Hergenrother will make its closest approach to the Sun on 22 October, at a distance of 1.36 AU.

From Cambridge on the day of perihelion it will be visible in the evening sky, becoming accessible around 18:58 (EDT), 44° above your south-eastern horizon, as dusk fades to darkness. It will then reach its highest point in the sky at 20:26, 48° above your southern horizon. It will continue to be observable until around 00:30, when it sinks below 21° above your western horizon.

The events that comprise the 2012 apparition of 168P/Hergenrother are as follows:

Date Event
22 Oct 2012Comet 168P/Hergenrother passes perihelion

The table below lists the times when 168P/Hergenrother will be visible from Cambridge day-by-day through its apparition:

Date Constellation Comet visibility
01 Oct 2012CapricornusVisible from 19:31 until 00:10
Highest at 21:40, 31° above S horizon
03 Oct 2012CapricornusVisible from 19:28 until 00:14
Highest at 21:32, 33° above S horizon
05 Oct 2012CapricornusVisible from 19:24 until 00:17
Highest at 21:24, 35° above S horizon
07 Oct 2012CapricornusVisible from 19:21 until 00:19
Highest at 21:16, 36° above S horizon
09 Oct 2012CapricornusVisible from 19:18 until 00:21
Highest at 21:08, 38° above S horizon
11 Oct 2012AquariusVisible from 19:14 until 00:23
Highest at 21:01, 40° above S horizon
13 Oct 2012AquariusVisible from 19:11 until 00:24
Highest at 20:54, 41° above S horizon
15 Oct 2012AquariusVisible from 19:08 until 00:25
Highest at 20:47, 43° above S horizon
17 Oct 2012AquariusVisible from 19:05 until 00:25
Highest at 20:41, 45° above S horizon
19 Oct 2012AquariusVisible from 19:02 until 00:26
Highest at 20:35, 46° above S horizon
21 Oct 2012AquariusVisible from 18:59 until 00:26
Highest at 20:28, 48° above S horizon
23 Oct 2012AquariusVisible from 18:56 until 00:26
Highest at 20:22, 49° above S horizon
25 Oct 2012PegasusVisible from 18:54 until 00:26
Highest at 20:17, 50° above S horizon
27 Oct 2012PegasusVisible from 18:51 until 00:26
Highest at 20:11, 52° above S horizon
29 Oct 2012PegasusVisible from 18:49 until 00:26
Highest at 20:06, 53° above S horizon
31 Oct 2012PegasusVisible from 18:46 until 00:25
Highest at 20:00, 54° above S horizon
02 Nov 2012PegasusVisible from 18:44 until 00:25
Highest at 19:55, 56° above S horizon
04 Nov 2012PegasusVisible from 17:42 until 23:25
Highest at 18:50, 57° above S horizon
06 Nov 2012PegasusVisible from 17:40 until 23:24
Highest at 18:45, 58° above S horizon
08 Nov 2012PegasusVisible from 17:38 until 23:24
Highest at 18:41, 59° above S horizon
10 Nov 2012PegasusVisible from 17:36 until 23:23
Highest at 18:36, 60° above S horizon

A more detailed table of 168P/Hergenrother's position on each night is available here. A diagram of the orbit of 168P/Hergenrother is available here.

Finder chart

The chart below shows the path of 168P/Hergenrother 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 168P/Hergenrother is currently available.

The comet's position at perihelion will be:

Object Right Ascension Declination Constellation Magnitude
Comet 168P/Hergenrother 21h49m40s 1°11'N Aquarius 9.9

The coordinates are given in J2000.0.

The sky on 4 Apr 2025

The sky on 4 April 2025
Sunrise
06:19
Sunset
19:13
Twilight ends
20:51
Twilight begins
04:41


Waxing Crescent

48%

6 days old

Planets
Rise Culm. Set
Mercury 05:38 11:38 17:39
Venus 05:06 11:25 17:44
Moon 10:39 18:50 02:54
Mars 11:59 19:37 03:16
Jupiter 09:18 16:50 00:23
Saturn 05:46 11:34 17:23
All times shown in EDT.

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 23 Feb 2025.

Image credit

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

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