Comet Chasing in January
Comet chasing is the visual observation of telescopic comets. Jump to: Observing synopses Summary data Buy me a Coffee
We have three comets visible in small telescopes this month, and one visible in a 6-inch telescope. See the Observing Synopses for which comets are visible from your latitude, the best dates and the time of night.
3I/ATLAS is the 3rd interstellar comet. It is currently magnitude 12.1 and fading rapidly. It passed closest to the sun on October 29 at a distance of 1.4 AU. See below for information about observing it in the telescope.
C/2024 E1 (Wierzchos) will reach perihelion on January 20 2026. It is currently predicted to reach maximum brightness of magnitude 8.4 in late January.
24P/Schuamasse is a periodoc comet with an 8.2 year orbital period. Perihelion is on January 8, 2026. It is predicted to reach maximum brightness of magnitude 10 in early January.
C/2025 A6 (Lemmon) is an amazing comet that brightened quickly in late August and became a naked eye object in October and November. There were reports of fans, streamers, and other structures apparent in the eyepiece at high magnification. Its been hiding in the glare of the sun, but will be moving into the morning sky in January.
C/2025 T1 (ATLAS) will reach perihelion in early December. It reached maximum brightness of magnitude 11.2 in mid November. This is currently the best comet to observe with small telescopes.
C/2025 K1 (ATLAS) fragmented, splitting into at least three parts (November 10). It has since faded. This comet was discovered on May 24 and is currently magnitude 14.5. It passed perihelion on October 8.
240P/NEAT is a periodic comet with a 7.6 year orbital period. Perihelion is on December 19. It is predicted to reach maximum brightness of magnitude 13 in early December.
235P/LINEAR is a periodic comet with a 6.4 year orbital period. Perihelion is on December 22 at a distance of 2.0 AU. It is currently predicted to reach maximum brightness of magnitude 12.5 in late April 2026.
210P/Christensen is a periodic comet with a 5.6 year orbital period. Perihelion is on November 22, when it will also be within 0.5 AU of the earth.
C/2025 R2 (SWAN) was identified by Vladimir Bezugly in SWAN images around 2025-09-11 (visible in SWAN since at least Sep 4, with STEREO-A/HI-1 detections into late August. C/2025 R2 (SWAN) is past perihelion, which occurred in mid September 2025. On September 12 this comet passed within 0.3 AU of the earth. It reached maximum brightness in late September
C/2021 G2 (ATLAS) is past perihelion, which occurred in early September 2024. It reached maximum brightness of magnitude 14 in late August.
29P/Schwassmann-Wachmann has frequent outbursts, typically resulting in a brightening of 1 - 4.0 magnitudes. It varies in its distance from the Sun from 5.8 AU (at perihelion) to 6.3 AU (at aphelion), which is an unusually small variation for a comet, and remains quite far from the sun at all times. This means that it can be observed more or less continuously. See Mission 29P from the BAA for up to date information.
C/2014 UN271 (Bernardinelli-Bernstein) is an interesting Oort cloud comet that was reported as a result of the Dark Energy Survey. Soon after it was made public, images showed a cometary coma. Discovery credit goes to Pedro Bernardinelli and Gary Bernstein. This is a remarkable comet that was at 29 AU in 2014, with a perihelion of 10.9 AU in 2031. Its orbit extends out to 40,000 AU! It was unusually bright for its distance. HST observations that isolate the nucleus estimate the diameter to be between 120 and 140 km, making this possibly the largest comet nucleus yet measured. Because of its distant perihelion, this comet is not expected to become bright enough to be visually observed except in large instruments, and not until the end of the decade, but it is likely going to be the subject of intense scientific scrutiny.
Comets that have apparently di
sintegrated: C/2025 F2, C/2024 G3, C/2024 S1 (ATLAS), C/2022 S3 (PANSTARRS), C/2021 P4 (ATLAS), C/2020 Q1 (Borisov), C/2020 P1 (NEOWISE), and C/2019 Y4 (ATLAS). Beware that various sources often fail to keep track of whether or not a comet still exists!Comet Visibility in the Eyepiece
When you read below that a particular aperture is required to see a comet you can have a reasonable degree of confidence that the comet can in fact be seen in the eyepiece.
This
page uses code developed for SkyTools to predict the visibility of a comet. Predicting how much
aperture is required to see a comet is a very complex task. The magnitude
alone is a very poor predictor. SkyTools considers the magnitude, coma
diameter, and degree of concentration of the comet, based on recent
observations.The predictions are made for a Country/Suburban site,
which is approximately
Bortle
5, unless
indicated otherwise. But always
remember, comets are like cats. They both have tails and do what they want, and
not always what we expect. This is one of the things that makes comet chasing
interesting!
Observing
Synopses for January
Explanation
of Comet Synopses and charts (read this if you have questions) C/2024 E1 (Wierzchos): A
southern hemisphere evening comet visible in small telescopes at a dark site, or
a 6-inch (15 cm) under a country sky 24P/Schaumasse: A morning
comet visible in small telescopes at a dark site, or a 6-inch (15 cm) under a
country sky C/2025 A6 (Lemmon): A
southern hemisphere morning comet visible in small telescopes at a dark site, or
a 6-inch (15 cm) under a country sky 29P/Schwassmann-Wachmann:
A morning comet visible in a 6-inch (15 cm) telescope at a dark site, or a
12.5-inch (32 cm) under a country sky C/2025 T1 (ATLAS): A
northern hemisphere evening comet visible in an 8-inch (20 cm) telescope at a
dark site 3I/ATLAS: A morning comet
visible in an 10-inch (20 cm) telescope at a dark site, or a 24-inch telescope
under a country sky 240P/NEAT: An evening
comet visible in an 8-inch (20 cm) telescope at a dark site, or a 14-inch (36
cm) under a country sky 235P/LINEAR: A morning
comet visible in a 10-inch (25 cm) telescope at a dark site Summary
Data for This Month's Telescopic Comets
This comet begins the month in Sagittarius at magnitude 9.6.
Look for a 2' coma, diffuse condensation at center. It should brighten by about
1.2 magnitudes, moving into Grus by month's end. The best visibility is late in
the month as seen from the southern hemisphere. FINDER
CHART
Latitude
Visibility January 3
Visibility January 10
Visibility January 17
Visibility January 24
Visibility January 31
Nights Visible
55o
N
Not visible
Not visible
Not visible
Not visible
Not visible
40o
N
Not visible
Not visible
Not visible
Not visible
Not visible
Equator
Not visible
Not visible
Not visible
Not visible
Not visible
29-
30o S
Not visible
Not visible
Not visible
Very low in the western sky
during evening twilight at ~20:10
Low in the western sky during
evening twilight at ~20:10
18-
This comet begins the month in Coma Berenices at magnitude 10.0.
Look for a 3.5' coma, center much brighter than edges, though still diffuse. It
should fade slowly, moving into Bootes by month's end. FINDER
CHART
Latitude
Visibility January 3
Visibility January 10
Visibility January 17
Visibility January 24
Visibility January 31
Nights Visible
55o
N
High during morning twilight at
~06:20
High in moonlight at ~06:00
High during morning twilight at
~06:10
High during morning twilight at
~06:00
High during morning twilight at
~06:00
1-
40o
N
High during morning twilight at
~06:00
High in moonlight at ~05:40
High during morning twilight at
~06:00
High during morning twilight at
~05:50
High during morning twilight at
~05:50
1-
Equator
High during morning twilight at
~05:00
High during morning twilight at
~04:50
High during morning twilight at
~04:50
High during morning twilight at
~05:00
High during morning twilight at
~05:10
1-
30o S
Fairly high during morning
twilight at ~03:50
Fairly high during morning
twilight at ~03:50
Fairly high during morning
twilight at ~03:50
High during morning twilight at
~04:00
High during morning twilight at
~04:10
1-
This comet begins the month in Scorpius at magnitude 9.6. Look
for a 2.5' coma, condensation is a bright diffuse spot at center of coma. It
should fade by about 1.3 magnitudes, moving into Ara by month's end. The best
visibility is mid-month as seen from the southern hemisphere. FINDER
CHART
Latitude
Visibility January 3
Visibility January 10
Visibility January 17
Visibility January 24
Visibility January 31
Nights Visible
55o
N
Not visible
Not visible
Not visible
Not visible
Not visible
40o
N
Not visible
Not visible
Not visible
Not visible
Not visible
Equator
Not visible
Low in the eastern sky during
morning twilight at ~05:10
Low in the southern sky during
morning twilight at ~05:10
Fairly high in the southern sky
during morning twilight at ~05:10
Fairly high in the southern sky
during morning twilight at ~05:10
1-
30o S
Low in the eastern sky during
morning twilight at ~03:50
Fairly high in the eastern sky
during morning twilight at ~03:50
Fairly high in the eastern sky
during morning twilight at ~04:00
Fairly high during morning
twilight at ~04:00
High during morning twilight at
~04:10
1-
This comet begins the month in Leo at magnitude 12.7 after an
apparent outburst. Look for a 1' coma, diffuse condensation at center. It should
fade as the outburst subsides. FINDER
CHART
Latitude
Visibility January 3
Visibility January 10
Visibility January 17
Visibility January 24
Visibility January 31
Nights Visible
55o
N
Fairly high in moonlight at
~05:30
Fairly high in moonlight at
~04:10
Fairly high at ~03:40
Fairly high at ~03:20
Not visible
1-
40o
N
High during morning twilight at
~05:50
High in moonlight at ~04:00
High at ~03:40
High at ~03:20
Fairly high in moonlight at
~05:30
1-
Equator
High during morning twilight at
~05:00
High in moonlight at ~04:00
High at ~03:40
High at ~03:20
High during morning twilight at
~05:10
1-
30o S
High during morning twilight at
~03:40
High in moonlight at ~03:30
High during morning twilight at
~03:40
High at ~03:20
High during morning twilight at
~04:10
1-
This comet begins the month in Aquila at magnitude 10.9. Look
for a 2' coma, center much brighter than edges, though still diffuse. It should
fade rapidly, moving into Aquarius by month's end. FINDER
CHART
Latitude
Visibility January 3
Visibility January 10
Visibility January 17
Visibility January 24
Visibility January 31
Nights Visible
55o
N
Low in the western sky during
evening twilight at ~17:40
Not visible
Not visible
Not visible
Not visible
1-14
40o
N
Low in the western sky during
evening twilight at ~18:10
Not visible
Not visible
Not visible
Not visible
1-15
Equator
Not visible
Not visible
Not visible
Not visible
Not visible
1-7
30o S
Not visible
Not visible
Not visible
Not visible
Not visible
This comet begins the month in Leo at magnitude 12.1. Look for a
2' coma, diffuse condensation at center. It should fade rapidly, moving into
Gemini by month's end. FINDER
CHART
Latitude
Visibility January 3
Visibility January 10
Visibility January 17
Visibility January 24
Visibility January 31
Nights Visible
55o
N
Not visible
High at ~01:30
Not visible
Not visible
Not visible
1-28
40o
N
Not visible
High at ~01:10
High at ~00:40
Not visible
Not visible
1-29
Equator
Not visible
High at ~00:30
High at ~00:40
Not visible
Not visible
1-29
30o S
Not visible
High in moonlight at ~01:10
Not visible
Not visible
Not visible
1-30
This comet begins the month in Aries at magnitude 12.6. Look for
a 50" coma, center much brighter than edges, though still diffuse. It
should fade by about 0.5 magnitudes, moving into Taurus by month's end. FINDER
CHART
Latitude
Visibility January 3
Visibility January 10
Visibility January 17
Visibility January 24
Visibility January 31
Nights Visible
55o
N
High during evening twilight at
~17:50
High at ~20:00
High at ~19:30
High in moonlight at ~19:10
High during evening twilight at
~18:30
1-
40o
N
High during evening twilight at
~18:10
High at ~20:00
High at ~19:30
High in moonlight at ~19:10
High during evening twilight at
~18:40
1-
Equator
High during evening twilight at
~19:10
High at ~20:00
High at ~19:40
High in moonlight at ~19:30
High during evening twilight at
~19:20
1-
30o S
High during evening twilight at
~20:20
High during evening twilight at
~20:40
Fairly high during evening
twilight at ~20:30
Fairly high during evening
twilight at ~20:30
Fairly high during evening
twilight at ~20:10
1-
This comet begins the month in Libra at magnitude 13.2. Look for
a 1' coma, diffuse condensation at center. It should brighten slowly. FINDER
CHART
Latitude
Visibility January 3
Visibility January 10
Visibility January 17
Visibility January 24
Visibility January 31
Nights Visible
55o
N
Not visible
Not visible
Not visible
Not visible
Not visible
1-
40o
N
Not visible
Fairly high in the southern sky
during morning twilight at ~05:50
Fairly high in the southern sky
during morning twilight at ~05:50
Fairly high in the southern sky
during morning twilight at ~06:00
Fairly high in the southern sky
during morning twilight at ~05:50
1-
Equator
High during morning twilight at
~04:50
High during morning twilight at
~04:50
High during morning twilight at
~05:00
High during morning twilight at
~05:00
High during morning twilight at
~05:10
1-
30o S
Fairly high during morning
twilight at ~03:40
Fairly high during morning
twilight at ~03:50
High during morning twilight at
~03:50
High during morning twilight at
~04:00
High during morning twilight at
~04:10
1-
Comets
brighter than 16th magnitude. This table is
updated as necessary. The last column indicates the date of the last
observation used to compute these values. The constellation listed is
where the comet was on the first of the month.
| Comet | Constellation |
January 1st |
January 15th |
January 31st |
Observations as of (UT) | |||
| Mag | Diam | Mag | Diam | Mag | Diam | |||
| C/2025 A6 (Lemmon) | Scorpius | 9.6 | 2.5' | 10.3 | 2.4' | 10.9 | 2.4' | 2025 November 21 |
| C/2024 E1 (Wierzchos) | Sagittarius | 9.6 | 1.5' | 8.7 | 1.7' | 8.4 | 2.2' | 2025 December 10 |
| 24P/Schaumasse | Coma Berenices | 10.0 | 3.5' | 10.0 | 3.5' | 10.4 | 3.4' | 2025 December 28 |
| C/2025 T1 (ATLAS) | Aquila | 10.9 | 1.8' | 11.8 | 1.6' | 12.9 | 1.4' | 2025 December 28 |
| 3I/ATLAS | Leo | 12.1 | 1.8' | 13.2 | 1.6' | 14.5 | 1.3' | 2025 December 28 |
| 198P/ODAS | Taurus | 12.3 | 1.9' | 12.6 | 1.7' | 12.9 | 1.5' | 2021 November 30 |
| 240P/NEAT | Aries | 12.6 | 51" | 12.8 | 47" | 13.1 | 41" | 2025 December 28 |
| 29P/Schwassmann-Wachmann | Leo | 12.7 | 59" | 12.6 | 1.0' | 12.5 | 1.1' | 2025 December 27 |
| 235P/LINEAR | Libra | 13.2 | 60" | 13.1 | 1.1' | 13.0 | 1.1' | 2025 December 20 |
| 210P/Christensen | Libra | 13.5 | 60" | 14.5 | 55" | 15.3 | 53" | 2025 December 25 |
| C/2025 R2 (SWAN) | Pisces | 13.9 | 1.6' | 14.8 | 1.3' | 15.6 | 1.1' | 2025 December 27 |
| C/2022 N2 (PANSTARRS) | Aries | 14.3 | 58" | 14.5 | 55" | 14.7 | 51" | 2025 November 26 |
| C/2025 K1 (ATLAS) | Andromeda | 14.5 | 1.1' | 15.6 | 47" | 16.6 | 36" | 2025 November 28 |
| 240P-B/NEAT | Aries | 14.8 | 47" | 15.0 | 42" | 15.3 | 38" | 2025 November 28 |
| C/2022 QE78 (ATLAS) | Leo | 15.0 | 56" | 15.0 | 57" | 15.0 | 57" | 2025 December 27 |
| C/2024 T5 (ATLAS) | Eridanus | 15.1 | 30" | 15.1 | 30" | 15.0 | 29" | 2025 December 27 |
| C/2025 R3 (PANSTARRS) | Pegasus | 16.9 | 24" | 16.5 | 24" | 15.8 | 24" | 2025 December 15 |
For information about specific comets see Gary W. Kronk's Cometography
Make your own visual observing custom charts for your location and telescope/binoculars: Software for visual comet observing
Select comets that are appropriate for your
imaging system, and plan when they are best imaged: Software
for comet imaging
| Links
Skyhound's Guide
to Comets
|