Latest image

Comet C/2020 M3 (ATLAS)
Comet C/2020 M3 (ATLAS), obtained on 2020 Nov. 21 (21h49-22h22UT) with 19-cm, f/4 Flat Field Camera and astro modified Canon EOS 700D DSLR. Exposure time was 30x60 seconds at ISO 3200.
Copyright © 2020 by H. Mikuz, Črni Vrh Observatory.

Welcome to COBS!

Comet Observation database (COBS) saw first light in 2010 and is maintained by Crni Vrh Observatory. It is a free and unique service for comet observers worldwide which allows submission, display and analysis of comet data in a single location.

Amateur astronomers can make valuable contributions to comet science by observing comets and submitting their observations to COBS as professional astronomers typically do not have telescope time required to acquire regular observations. We therefore encourage comet observers worldwide to submit their observations and contribute to the COBS database.

Registered observers may submit observations using a web based form which which stores the observations in an SQL database and stores them in ICQ format. Observations may be queried and plotted in the web site or exported for further processing, analysis and publication. The database currently contains more than 257000 comet observations of more than 1400 different comets and represents the largest available database of comet observations.

The data stored in COBS is freely available to everyone who honors our data usage policy. Please cite COBS as the reference if you use it for comet studies.

Latest lightcurve

Light-curve of C/2020 S3 (Erasmus) (Mar 05, 2021).

Type Comet name Obs date Mag App T Pow Dia DC Tail PA Obs
V C/2020 T2 2021 03 04.95 13.4 53.1 L 215 0.8 s3/ HAR11
V C/2021 A2 2021 03 04.93 13.8 53.1 L 215 0.8 1 HAR11
V 156P 2021 03 04.92 13.8 53.1 L 215 0.5 2/ HAR11
V 141P 2021 03 04.91 14.0 53.1 L 215 0.25 s4 HAR11
V C/2019 L3 2021 03 04.91 13.0 53.1 L 215 0.8 4 HAR11
V 141P 2021 03 04.89 13.5 30.5 L 188 0.7 1/ KAR02
V C/2019 L3 2021 03 04.87 12.8 30.5 L 188 0.6 4 KAR02
C 141P 2021 03 03.87 13.7 25.0 T A440 1 0.6m 63 MAS01
C 141P 2021 03 03.87 12.9 25.0 T A440 2 MAS01
C C/2021 A4 2021 03 03.78 12.8 5.4 A a900 1.8 PAR03
C C/2021 A4 2021 03 03.78 12.5 5.4 A a900 2.2 PAR03
C C/2021 A2 2021 03 02.95 13.2 10.0 R A800 0.5 DEK01
C C/2021 A4 2021 03 02.92 14.7 10.0 R a930 0.5 DEK01
C 11P 2021 03 02.89 14.2: 54.0 L a 1 1 2 KUT
C C/2021 A2 2021 03 02.85 13.7 54.0 L a 1 1.2 5 KUT
V 156P 2021 03 02.81 14.1 53.1 L 215 0.6 2/ HAR11
C C/2019 L3 2021 03 02.81 11.7 10.0 R B100 1 DEK01
V 156P 2021 03 02.80 13.0 25.4 L 150 1.1 3 MEY
V C/2021 A4 2021 03 02.80 12.4 53.1 L 155 1.6 2 HAR11
V C/2019 L3 2021 03 02.80 13.0 53.1 L 155 0.6 4 HAR11


Comet Observing Planner

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Current comet magnitudes and observable region

Comet name Mag Trend Observable Visiblity
10P/Tempel 10.5 bright 75N to 90S Early evening Early evening
7P/Pons-Winnecke 11.0 bright 90N to 80S Best morning Early evening
C/2020 X3 (SOHO) 12.5 fade 68N to 90S Evening Best evening
246P/NEAT 13.0 bright 67N to 90S Early evening Best morning
C/2019 L3 (ATLAS) 13.0 bright 90N to 38S All night Never up
C/2019 N1 (ATLAS) 13.0 fade 5N to 90S Never up Never up
C/2021 D1 (SWAN) 13.5 steady 90N to 73S Evening Early evening
28P/Neujmin 13.5 steady 79N to 90S Poor elongation Poor elongation
C/2021 A2 (NEOWISE) 13.5 fade 90N to 51S Best evening Early evening
156P/Russell-LINEAR 13.5 fade 90N to 49S Best evening Early evening
C/2020 T2 (Palomar) 13.5 bright 90N to 58S Best morning Best morning
P/2013 PA104 (PANSTARRS) 13.5 fade 84N to 90S Best evening Best evening
C/2019 F1 (ATLAS-Africano) 14.0 bright 30N to 90S Never up Never up
C/2021 A4 (NEOWISE) 14.0 fade 90N to 81S Best evening Evening
29P/Schwassmann-Wachmann 14.0 steady 90N to 66S Evening Early evening
141P/Machholz 14.0 fade 90N to 86S Best evening Best evening

The observable region is an approximate indication of the latitude at which the comet may be seen. The period when visible is calculated for latitude 45°N and 45°S.

Latest news

Mar. 02, 2021

New Comet C/2021 C4 (ATLAS)

CBET 4937 & MPEC 2021-D113, issued on 2021, February 26, announce the discovery of an apparently asteroidal object (magnitude ~19) on CCD images taken on Feb. 12.6 UT with a 0.5-m f/2 Schmidt reflector at Haleakala, Hawaii, in the course of the "Asteroid Terrestrial-Impact Last Alert System" (ATLAS) search program. This object has been found to show cometary appearance by CCD astrometrists elsewhere after the object was posted on the Minor Planet Center's PCCP webpage due to its orbit. The new comet has been designated C/2021 C4 (ATLAS).


Feb. 26, 2021

Comet makes a pit stop near Jupiter's asteroids

After traveling several billion miles toward the Sun, a wayward young comet-like object orbiting among the giant planets has found a temporary parking place along the way. The object has settled near a family of captured ancient asteroids, called Trojans, that are orbiting the Sun alongside Jupiter. This is the first time a comet-like object has been spotted near the Trojan population.


Feb. 15, 2021

The comet that killed the dinosaurs

Scientists have put forth a new theory that could explain the origin and journey of the comet that killed the Chicxulub impactor and others like it.


Feb. 06, 2021

New Comet C/2021 B3 (NEOWISE)

CBET 4929 & MPEC 2021-C16, issued on 2021, February 04, announce the discovery of a comet (magnitude ~19) in infrared images obtained during Jan. 22 UT with the Near-Earth Object Wide-field Infrared Survey Explorer (or NEOWISE; formerly the WISE earth-orbiting satellite). The new comet has been designated C/2021 B3 (NEOWISE).


Jan. 31, 2021

New Comet C/2021 A1 (Leonard)

CBET 4907 & MPEC 2021-A99, issued on 2021, January 10, announce the discovery of a comet (magnitude ~19.5) by Gregory J. Leonard on CCD images taken on Jan. 3.54-3.56 UT with the Mount Lemmon Survey's 1.5-m reflector. The new comet has been designated C/2021 A1 (Leonard).