Latest image

Comet C/2020 F3 (NEOWISE)
Comet C/2020 F3 (NEOWISE) obtained on 2020 July 27 (21h10-21h25UT) with 300 mm, f/4.7 lens and Canon EOS 6D DSLR. Exposure time was 15x60 seconds at ISO 1600.
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 255000 comet observations of more than 1300 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) (Nov 28, 2020).

Type Comet name Obs date Mag App T Pow Dia DC Tail PA Obs
V C/2020 S3 2020 11 27.91 7.3: 8.0 B 20 GUOaa
V C/2020 S3 2020 11 27.28 7.1 10.0 B 25 6 6 DES01
C 220P 2020 11 26.77 19.7 50.0 C a 60 PAP04
V C/2020 S3 2020 11 26.73 7.1 10.0 B 25 3 7 MAT08
V C/2020 S3 2020 11 26.53 7.1 5.0 B 10 5 7 HER02
V C/2020 M3 2020 11 26.52 8.0 5.0 B 10 10 2 HER02
V C/2020 S3 2020 11 26.30 7.1 7.0 B 15 4 5 SOU01
V C/2020 S3 2020 11 26.29 7.1 15.0 L 38 4 5 SOU01
V C/2020 S3 2020 11 26.28 7.1 10.0 B 25 7 5/ DES01
V C/2020 S3 2020 11 26.14 7.0 15.0 L 23 3.5 6 NOV01
C P/2013 TL117 2020 11 26.13 18.0 50.0 C a 60 0.2 PAP04
C 99P 2020 11 26.13 18.5 50.0 C a 60 0.3 PAP04
C P/2005 XA54 2020 11 26.12 17.2 50.0 C a 60 0.5 PAP04
V C/2020 M3 2020 11 26.12 8.5: 27.0 L 90 DES01
V C/2020 M3 2020 11 26.08 8.6 19.0 L 73 6 3 KWI
C 191P 2020 11 25.78 18.5 50.0 C a 60 PAP04
V C/2020 S3 2020 11 25.30 7.1 7.0 B 15 5 6 SOU01
V C/2020 S3 2020 11 25.30 7.0 10.0 B 20 4 7 0.2 270 GOI
V C/2020 S3 2020 11 25.29 7.1 15.0 L 42 5 6 SOU01
V C/2020 S3 2020 11 25.28 7.2 10.0 B 25 7 4 DES01


Comet Observing Planner

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Current comet magnitudes and observable region

Comet name Mag Trend Observable Visiblity
C/2020 S3 (Erasmus) 6.5 bright 67N to 90S Early evening Early evening
141P-B/Machholz 6.5 fade 74N to 90S Early evening Early evening
C/2020 M3 (ATLAS) 8.5 fade 90N to 68S Best morning Best morning
141P-A/Machholz 9.0 fade 80N to 90S Early evening Early evening
141P-D/Machholz 9.5 fade 80N to 90S Early evening Early evening
141P/Machholz 10.0 bright 80N to 90S Evening Evening
88P/Howell 10.0 fade 67N to 90S Evening Evening
156P/Russell-LINEAR 10.5 fade 90N to 84S Best evening Best evening
C/2019 Y4 (ATLAS) 12.0 steady 81N to 90S Best morning Best morning
D/1978 R1 (Haneda-Campos) 12.5 fade 90N to 77S Best morning Best morning
C/2019 N1 (ATLAS) 12.5 bright 70N to 90S Early evening Early evening
C/2017 T2 (PANSTARRS) 13.0 fade 69N to 90S Poor elongation Poor elongation
398P/Boattini 13.0 bright 77N to 90S Best morning Best morning
162P/Siding Spring 13.0 steady 72N to 90S Evening Best evening
29P/Schwassmann-Wachmann 13.0 steady 90N to 64S Best evening Best evening
75D/Kohoutek 13.5 bright 90N to 67S Best evening Best evening
P/2013 PA104 (PANSTARRS) 13.5 fade 84N to 90S Best evening Best evening
246P/NEAT 14.0 steady 75N to 90S Poor elongation Poor elongation
141P-H/Machholz 14.0 steady 68N to 90S Poor elongation Poor elongation
C/2019 L3 (ATLAS) 14.0 bright 90N to 28S All night Never up

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

Oct. 29, 2020

Philae’s second touchdown site discovered at ‘skull-top’ ridge

After years of detective work, the second touchdown site of Rosetta’s Philae lander has been located on Comet 67P/Churyumov-Gerasimenko in a site that resembles the shape of a skull. Philae left its imprint in billions-of-years-old ice, revealing that the comet’s icy interior is softer than cappuccino froth.


Sep. 22, 2020

QHYCCD Camera type keys

In order to unify the camera type abbreviation keys of all QHYCCD camera models, we had to change some of the currently used camera type keys.


Sep. 21, 2020

Comet discovered to have its own northern lights

Comet 67P/Churyumov-Gerasimenko has its own far-ultraviolet aurora, data reveal. It is the first time such electromagnetic emissions in the far-ultraviolet have been documented on a celestial object other than a planet or moon.


Sep. 21, 2020

New Comet C/2020 S3 (Erasmus)

CBET 4885 & MPEC 2020-S119, issued on 2020, September 20, announce the discovery of a comet (magnitude ~18.5) by Nicolas Erasmus (South African Astronomical Observatory), in four 30-s CCD images taken in 5" seeing on Sept. 17.6 UT with a 0.5-m f/2 Schmidt reflector at Mauna Loa, Hawaii, in the course of the "Asteroid Terrestrial-Impact Last Alert System" (ATLAS) search program. The new comet has been designated C/2020 S3 (Erasmus).


Sep. 07, 2020

Rainbow comet with a heart of sponge

A permeable heart with a hardened facade –the resting place of Rosetta’s lander on comet 67P/Churyumov-Gerasimenko is revealing more about the interior of the 'rubber duck' shaped-body looping around the Sun.