Latest image

Comet 2I/Borisov
True color image of comet 2I/Borisov, obtained on 2019 Nov. 25 with RASA 11 and ZWO asi 294 mc Pro camera. Exposure time was 37x120sec.
Copyright © 2019 by Dan Bartlett

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 242000 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/2017 T2 (PANSTARRS) (Dec 13, 2019).

Type Comet name Obs date Mag App T Pow Dia DC Tail PA Obs
C 2I 2019 12 09.26 16.0 25.0 T A200 0.6 0.7m 321 MAS01
C 2I 2019 12 09.25 15.8 25.0 T A200 0.6 1.1m 322 MAS01
C 76P 2019 12 08.11 17.1 50.0 L a150 0.3 HILaa
C 78P 2019 12 08.10 13.9 50.0 L a150 0.5 HILaa
V C/2017 T2 2019 12 06.93 9.8 25.4 T 96 3 4/ 4.6m 187 COLac
V 2I 2019 12 06.71 15.7 40.0 L 261 0.3 2/ WYA
V 155P 2019 12 06.69 15.6 40.0 L 261 0.4 2 WYA
V C/2018 F4 2019 12 06.67 13.5 40.0 L 108 0.8 5/ WYA
V C/2017 T2 2019 12 06.16 10.5 20.0 T 40 & 1.4 4/ AGUaa
V C/2017 T2 2019 12 05.96 10.0 18.5 L 73 2.7 4 KWI
C C/2018 F4 2019 12 05.72 13.9 12.7 R a360 BUIaa
C 2I 2019 12 05.21 15.2 10.0 R A682 1.2 FRIaa
C 155P 2019 12 05.16 15.3 10.0 R C369 1.4 0.07 294 FRIaa
C 78P 2019 12 05.11 15.7 10.0 R C610 1.3 0.05 278 FRIaa
C 114P 2019 12 05.09 13.5 35.0 T a360 0.56 BUCaa
C 260P 2019 12 05.08 12.0 35.0 T a360 1.7 BUCaa
C 384P 2019 12 05.04 17.9 10.0 R G461 0.7 0.2m 252 FRIaa
V 260P 2019 12 05.00 13.0 30.0 L 133 0.9 3 HAR11
C C/2018 N2 2019 12 05.00 11.4 35.0 T a360 1.3 BUCaa
C C/2017 T2 2019 12 04.99 9.7 35.0 T a360 2 BUCaa


Comet Observing Planner

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Current comet magnitudes and observable region

Comet name Mag Trend Observable Visiblity
C/2017 T2 (PANSTARRS) 10.0 bright 90N to 39S All night Never up
C/2018 N2 (ASASSN) 11.5 fade 90N to 51S Best evening Early evening
C/2008 Y12 (SOHO) 12.5 bright 56N to 90S Best morning Best morning
260P/McNaught 13.0 fade 90N to 43S All night Never up
29P/Schwassmann-Wachmann 13.5 steady 90N to 77S Best evening Best evening
155P/Shoemaker 14.0 steady 90N to 78S Best morning Early evening
114P/Wiseman-Skiff 14.0 steady 90N to 57S 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

Dec. 13, 2019

Interstellar Comet 2I/Borisov swings past the Sun

HUBBLE SNAPS THE BEST CLOSE-UPS YET OF SPEEDY VISITOR FROM THE STARS When astronomers see something in the universe that at first glance seems like one-of-a-kind, it's bound to stir up a lot of excitement and attention. Enter comet 2I/Borisov. This mysterious visitor from the depths of space is the first identified comet to arrive here from another star. We don't know from where or when the comet started heading toward our Sun, but it won't hang around for long. The Sun's gravity is slightly deflecting its trajectory, but can't capture it because of the shape of its orbit and high velocity of about 100,000 miles per hour. Telescopes around the world have been watching the fleeting visitor. Hubble has provided the sharpest views as the comet skirts by our Sun. Since October the space telescope has been following the comet like a sports photographer following horses speeding around a racetrack. Hubble revealed that the heart of the comet, a loose agglomeration of ices and dust particles, is likely no more than about 3,200 feet across, about the length of nine football fields. Though comet Borisov is the first of its kind, no doubt there are many other comet vagabonds out there, plying the space between stars. Astronomers will eagerly be on the lookout for the next mysterious visitor from far beyond.


Oct. 17, 2019

Hubble observes new Interstellar Visitor [HEIC1918]

On 12 October 2019, the NASA/ESA Hubble Space Telescope provided astronomers with their best look yet at an interstellar visitor – Comet 2I/Borisov – which is believed to have arrived here from another planetary system elsewhere in our galaxy.


Sep. 27, 2019

Naming of new interstellar visitor: 2I/Borisov

A new object from interstellar space has been found within the Solar System, only the second such discovery of its kind. Astronomers are turning their telescopes towards the visitor, which offers a tantalising glimpse beyond our Solar System and raises some puzzling questions. The object has been given the name 2I/Borisov by the IAU.


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.