Latest image

Comet C/2019 Q4 (Borisov)
Comet C/2019 Q4 (Borisov) obtained on 2019 Sep. 11 (2h52-3h15UT), with 60-cm, f/3.3 Deltagraph telescope and CCD. Exposure time was 3x60 seconds.
Copyright © 2019 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 241000 comet observations of more than 1200 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/2018 W2 (Africano) (Sep 15, 2019).

Type Comet name Obs date Mag App T Pow Dia DC Tail PA Obs
V C/2017 T2 2019 09 11.10 12.2 25.4 L 104 1.1 3/ MEY
V C/2017 T2 2019 09 11.10 11.5 30.0 L 96 1.9 2/ HAR11
V C/2018 N2 2019 09 11.09 11.6 25.4 L 104 1.5 5 MEY
V C/2018 N2 2019 09 11.09 10.8 30.0 L 96 2 4/ HAR11
V 260P 2019 09 11.08 12.1 25.4 L 104 1.1 5 MEY
V 260P 2019 09 11.08 12.3 30.0 L 133 0.8 6 2.5m 245 HAR11
V C/2018 W2 2019 09 11.07 9.8 25.4 L 64 4.5 2/ MEY
V C/2018 W2 2019 09 11.07 8.7 19.8 L 49 9 2 HAR11
V C/2018 W2 2019 09 11.06 10.0 20.0 L 42 & 5 2 SCH04
C 260P 2019 09 11.01 12.3 5.4 A A200 1.5 0.04 248 PAR03
C C/2018 N2 2019 09 11.01 12.6 5.4 A A200 1.5 0.04 190 PAR03
V C/2017 T2 2019 09 10.10 11.7 30.0 L 96 1.8 3 HAR11
V C/2018 N2 2019 09 10.09 11.6 30.0 L 96 2.1 5 HAR11
V 260P 2019 09 10.09 12.2 30.0 L 133 0.8 6 2.0m 220 HAR11
V C/2018 W2 2019 09 10.08 9.0 19.8 L 49 7 2 HAR11
V C/2017 T2 2019 09 09.74 11.6 40.0 L 75 1.8 5 YOS04
V 29P 2019 09 09.72 [14.0 40.0 L 257 YOS04
V 260P 2019 09 09.71 11.6 40.0 L 75 1.7 6 3.2m 225 YOS04
V C/2018 N2 2019 09 09.70 11.9 40.0 L 75 1.5 7 YOS04
V C/2018 W2 2019 09 09.69 9.6 40.0 L 36 6 2 YOS04


Comet Observing Planner

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Current comet magnitudes and observable region

Comet name Mag Trend Observable Visiblity
85P/Boethin 7.0 steady 90N to 66S Best morning Early evening
P/2008 Y12 (SOHO) 7.5 bright 71N to 90S Early evening Evening
289P/Blanpain 11.0 bright 70N to 90S Best morning Best morning
C/2018 N2 (ASASSN) 12.0 bright 90N to 62S Best morning Best morning
260P/McNaught 12.5 steady 90N to 59S Best morning Best morning
C/2017 T2 (PANSTARRS) 12.5 bright 90N to 65S Best morning Early evening
C/2008 Y12 (SOHO) 12.5 bright 56N to 90S Best morning Best morning
68P/Klemola 13.0 steady 78N to 90S Evening Best evening
29P/Schwassmann-Wachmann 13.5 steady 90N to 74S Best morning Best morning
C/2018 A6 (Gibbs) 14.0 steady 16N to 90S Never up 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.

Top news

Sep. 13, 2019

Newly discovered comet is likely interstellar visitor

A newly discovered comet has excited the astronomical community this week because it appears to have originated from outside the solar system. The official confirmation that comet C/2019 Q4 is an interstellar comet has not yet been made, but if it is interstellar, it would be only the second such object detected.


Latest news

Sep. 14, 2019

Astronomers May Have Found an Interstellar Comet. Here's Why That Matters.

It’s looking likely that a newly discovered comet is actually an interstellar interloper from beyond our solar system. Since its discovery on 30 August, more and more measurements of C/2019 Q4 (Borisov)—named after the amateur astronomer from Crimea who found it—indicate it isn’t orbiting our Sun. Even NASA now says the comet’s extrasolar origin is promising.


Sep. 14, 2019

Interstellar 2.0

Astronomers have spotted an object that looks likely to be a very rare visitor from outside our Solar System. If confirmed, this unusual body would be only the second interstellar object ever detected passing through our neighbourhood.


Sep. 12, 2019

A possible interstellar comet

A new comet just discovered by amateur astronomer Gennady Borisov is rocketing through the solar system too fast for the sun's gravity to hang onto it. Indeed, it appears to be a visitor from the stars. Interstellar Comet Borisov will make its closest approach to the sun and to Earth in Dec. 2019.


Aug. 14, 2019

An Unexpected Companion

Last week marked five years since ESA’s Rosetta probe arrived at its target, a comet named 67P/Churyumov-Gerasimenko (or 67P/C-G). Tomorrow, 13 August, it will be four years since the comet, escorted by Rosetta, reached its perihelion – the closest point to the Sun along its orbit.


Jul. 02, 2019

'Oumuamua is not an alien spacecraft. New analysis suggests a natural origin for our first interstellar visitor.

Early reports of the interstellar visitor 'Oumuamua's odd characteristics led some to speculate that the object could be an alien spacecraft, sent from a distant civilization to examine our star system. But a new analysis by an international team of 14 astronomers strongly suggests that 'Oumuamua has a purely natural origin.