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 245000 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) (Jan 18, 2020).

Type Comet name Obs date Mag App T Pow Dia DC Tail PA Obs
V C/2017 T2 2020 01 17.83 9.9 35.5 L 61 2.1 7 10.8m 120 CER01
V C/2017 T2 2020 01 17.79 10.3 25.0 L 42 4 5 WAR01
V C/2017 T2 2020 01 17.78 8.5 25.4 T 96 2.8 5 5.7m 121 COLac
V C/2018 N2 2020 01 17.77 12.4 25.0 L 91 1 4 WAR01
V C/2017 T2 2020 01 16.95 9.5 25.0 L 42 3 5 WAR01
V C/2017 T2 2020 01 16.92 9.9 40.0 L 90 1.5 5 2.4m 125 MAS01
V C/2017 T2 2020 01 16.90 9.4 30.0 L 69 3 4 8.0m 120 HAR11
C C/2017 T2 2020 01 16.89 9.0 35.0 T a180 4.3 BUCaa
V C/2017 T2 2020 01 16.88 9.2 5.0 B 18 5 4 KAR02
C C/2018 N2 2020 01 16.87 11.5 35.0 T a360 1.5 BUCaa
V C/2017 T2 2020 01 16.86 9.8 25.0 L 38 2.1 5 0.07 KUT
C 114P 2020 01 16.81 13.8 54.0 L a 10 0.7 2 KUT
V C/2017 T2 2020 01 16.80 9.6 18.5 L 73 2.7 4 KWI
V C/2018 N2 2020 01 16.80 12.5 54.0 L 180 1.2 3 KUT
V C/2018 N2 2020 01 16.78 12.3 25.4 L 104 0.9 2/ MEY
C 29P 2020 01 16.78 13.3 54.0 L a 10 0.9 3 KUT
V C/2017 T2 2020 01 16.77 9.6 25.4 L 64 4 4 0.1 115 MEY
V C/2017 T2 2020 01 16.77 10.5 32.0 L 80 3 7 0.07 182 PIL01
C C/2017 T2 2020 01 16.77 10.6 30.0 L B400 3.2 16.2m 154 DEK01
V C/2017 T2 2020 01 16.76 9.5 19.5 L 64 3 4 4.5m 120 HAR11


Comet Observing Planner

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Current comet magnitudes and observable region

Comet name Mag Trend Observable Visiblity
321P/SOHO 7.0 steady 69N to 90S Poor elongation Poor elongation
C/2017 T2 (PANSTARRS) 10.0 steady 90N to 33S All night Never up
C/2008 Y12 (SOHO) 12.5 bright 56N to 90S Best morning Best morning
C/2018 N2 (ASASSN) 12.5 fade 90N to 49S Best evening Early evening
155P/Shoemaker 13.5 steady 90N to 78S Best morning Best morning
29P/Schwassmann-Wachmann 14.0 steady 90N to 77S Evening Early 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

Jan. 07, 2020

New Comet C/2019 Y1 (ATLAS)

CBET 4708 & MPEC 2020-A72, issued on 2020, January 05, announce the discovery of a comet (magnitude ~18) in the course of the "Asteroid Terrestrial-Impact Last Alert System" (ATLAS) search program, in images taken on 2019, Dec 16 with a 0.5-m reflector + CCD. The new comet has been designated C/2019 Y1 (ATLAS).


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.