Latest image

Periodic comet 67P/Churyumov-Gerasimenko
Image of periodic comet 67P/Churyumov-Gerasimenko, obtained on 2021 Nov. 11 (2h54-3h30UT) with 15-cm, f/6 Maksutov-Cassegrain astrocamera and Conon EOS 6D DSLR. Image is a composition 18x120 second exposures.
Copyright © 2021 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 262000 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/2021 A1 (Leonard) (Nov 30, 2021).

Type Comet name Obs date Mag App T Pow Dia DC Tail PA Obs
C 29P 2021 11 30.93 10.2 31.5 C A260 7.9 CARah
C C/2021 A1 2021 11 30.50 8.1 43.0 Y a180 BUIaa
V C/2021 A1 2021 11 30.47 7.1 5.0 B 10 5 5 0.3 320 HER02
C C/2021 A1 2021 11 29.51 8.0 43.0 Y a300 BUIaa
V 19P 2021 11 29.49 10.5 20.0 L 70 4 5 MAT08
V 6P 2021 11 29.48 10.1 20.0 L 70 6 2 MAT08
C C/2021 A1 2021 11 29.22 8.1 28.0 T C012 10.15 JAMaa
C C/2021 A1 2021 11 29.22 7.2 9.0 R B754 14.66 JAMaa
V C/2019 L3 2021 11 29.17 9.7 12.0 R 30 3 5 MEY
V 67P 2021 11 29.16 8.9 12.0 R 30 4 5/ MEY
V C/2021 A1 2021 11 29.14 7.8 5.0 B 10 8 5/ MEY
C C/2021 A1 2021 11 29.07 8.4 35.0 T a300 5.26 BUCaa
C C/2019 L3 2021 11 28.86 9.7 35.0 T A200 5.45 BUCaa
C 29P 2021 11 28.84 10.6 35.0 T A200 6.39 BUCaa
V C/2021 A1 2021 11 28.50 7.2 5.0 B 10 7 5 0.2 315 HER02
V 67P 2021 11 28.29 9.0 22.0 L 60 5 4/ GOI
V C/2021 A1 2021 11 28.20 7.8: 15.0 L 30 NOVaa
V C/2021 A1 2021 11 28.20 7.8: 5.0 B 7 NOVaa
C C/2019 L3 2021 11 28.19 9.6 31.5 C A200 8.1 CARah
V C/2021 A1 2021 11 28.18 7.9 25.0 C 62 6 4 25.0m 300 DECaa


Comet Observing Planner

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Current comet magnitudes and observable region

Comet name Mag Trend Observable Visiblity
C/2021 A1 (Leonard) 7.0 bright 90N to 60S Early evening Early evening
C/2019 L3 (ATLAS) 9.5 bright 90N to 53S Best morning Early evening
67P/Churyumov-Gerasimenko 9.5 fade 90N to 63S Best morning Early evening
19P/Borrelly 10.0 bright 52N to 90S Evening Best morning
29P/Schwassmann-Wachmann 10.5 steady 90N to 58S Best morning Best morning
342P/SOHO 11.5 fade 62N to 90S Poor elongation Poor elongation
4P/Faye 11.5 fade 90N to 82S Best morning Best morning
8P/Tuttle 11.5 fade 40N to 90S Never up Never up
C/2017 K2 (PANSTARRS) 12.5 bright 90N to 74S Evening Early evening
73P-V/Schwassmann-Wachmann 13.0 fade 60N to 90S Early evening Evening
83D/Russell 13.5 bright 68N to 90S Early evening Early evening
C/2019 T4 (ATLAS) 13.5 bright 62N to 90S Early evening Best morning
181P/Shoemaker-Levy 13.5 bright 58N to 90S Evening Best evening
97P/Metcalf-Brewington 13.5 steady 85N to 90S Best evening Best morning
P/2013 PA104 (PANSTARRS) 13.5 fade 84N to 90S Best evening Best evening
9P/Tempel 1 14.0 bright 83N to 90S Early evening Early evening
110P/Hartley 14.0 bright 90N to 72S Best morning Best morning
57P/du Toit-Neujmin-Delporte 14.0 fade 72N to 90S Evening 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

Nov. 10, 2021

New Comet P/2021 U3 (Attard-Maury)

CBET 5064 & MPEC 2021-V21, issued on 2021, November 02, announce the discovery of a new comet (magnitude ~19) by A. Maury and G. Attard on CCD images taken on October 24.3 UT with the 0.28-m f/2.2 Rowe-Ackermann Schmidt astrograph at San Pedro de Atacama, Chile in the course of the MAP (W94) survey. The new comet has been designated P/2021 U3 (Attard-Maury). This is the 4th amateur comet discovery of 2021. It is also the second comet discovered using the synthetic tracking technique (using TYCHO software).


Oct. 25, 2021

To watch a comet form, a spacecraft could tag along for a journey toward the sun

A new article proposes that space probes could hitch a ride with 'centaurs' as they become comets. Along the way, the spacecraft would gather data that would otherwise be impossible to record -- including how comets, Earth-like planets, and even the solar system formed.


Oct. 02, 2021

New Comet P/2021 Q5 (ATLAS)

CBET 5029 & MPEC 2021-R98 , issued on 2021, September 06, announce the discovery of a new comet (magnitude ~17) on CCD images taken on August 29.6 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. The new comet has been designated P/2021 Q5 (ATLAS).


Sep. 30, 2021

New Comet C/2021 Q4 (Fuls)

CBET 5028 & MPEC 2021-Q102, issued on 2021, August 31 & September 02, announce the discovery of a new comet (magnitude ~20) on CCD images taken on August 26.2 UT with the Mt. Lemmon Survey (G96) 1.5-m reflector. The new comet has been designated C/2021 Q4 (Fuls).


Aug. 31, 2021

New Comet C/2021 P4 (ATLAS)

With the MPEC 2021-Q42 issued on 21 August 2021, the discovery of a new Magn comet is announced. 19.4 identified by the ATLAS-HKO program (T05).