Latest image

Comet C/2010 U3 (Boattini)
False color unfiltered image of comet C/2010 U3 (Boattini), obtained on 2019 Jun. 2 (21h32-21h40UT) with 60-cm, f/3.3 Deltagraph telescope and CCD. Exposure time was 6x60 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 240000 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 Y1 (Iwamoto) (Jun 19, 2019).

Type Comet name Obs date Mag App T Pow Dia DC Tail PA Obs
C C/2015 V2 2019 06 12.39 16.9 30.0 C C840 0.5 MAS01
C 68P 2019 06 12.30 15.6 30.0 C a840 0.4 MAS01
C 68P 2019 06 12.30 16.1 30.0 C a840 0.4 MAS01
C C/2018 N2 2019 06 12.20 13.1 50.0 T a 60 0.3 7 2.6m 186 PAUaa
V C/2018 R3 2019 06 11.89 10.3 20.0 T 50 4 2 LAB02
C C/2017 B3 2019 06 10.37 14.8 30.0 C a720 0.7 MAS01
C C/2017 B3 2019 06 10.37 14.4 30.0 C a720 0.7 0.7m 219 MAS01
C 260P 2019 06 09.34 16.9 30.0 C B760 0.4 0.8m 241 MAS01
C C/2016 R2 2019 06 08.89 14.1 50.0 L a150 0.9 HILaa
C C/2018 U1 2019 06 08.01 18.4 50.0 L a150 0.2 HILaa
V C/2018 R3 2019 06 07.94 8.5 10.0 B 25 10 2 GON05
C 74P 2019 06 07.94 16.3 50.0 L a150 0.4 HILaa
V C/2018 R3 2019 06 07.93 9.3 20.3 T 77 6 2/ GON05
C 29P 2019 06 07.21 13.0 50.0 L a150 2.8 HILaa
C C/2017 K2 2019 06 07.00 16.0 50.0 L a180 0.4 HILaa
C C/2019 D1 2019 06 06.02 14.4 10.0 R B642 2.2 0.04 254 FRIaa
C 68P 2019 06 06.02 15.2 50.0 L a150 0.4 HILaa
C 68P 2019 06 05.98 15.5 10.0 R B883 1.3 0.01 234 FRIaa
C C/2016 R2 2019 06 05.94 15.2 10.0 R B883 2.6 FRIaa
V C/2018 R3 2019 06 05.90 10.2 10.0 B 25 3 4 GUZ


Comet Observing Planner

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Limiting mag:
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Current comet magnitudes and observable region

Comet name Mag Trend Observable Visiblity
C/2018 R3 (Lemmon) 10.5 fade 90N to 38S All night Never up
C/2017 T2 (PANSTARRS) 12.5 bright 90N to 75S Early evening Early evening
C/2016 M1 (PANSTARRS) 13.0 fade 60N to 90S Early evening Evening
29P/Schwassmann-Wachmann 13.0 steady 90N to 76S Early evening Early evening
P/2008 Y12 (SOHO) 13.5 bright 60N to 90S Best morning Best morning
C/2008 Y12 (SOHO) 13.5 bright 60N to 90S Best morning Best morning
C/2017 M4 (ATLAS) 13.5 fade 47N to 90S Early evening Best morning
C/2018 N2 (ASASSN) 13.5 bright 90N to 84S Early evening Early evening
C/2018 W2 (Africano) 13.5 bright 90N to 28S All night Never up
C/2018 A6 (Gibbs) 14.0 steady 37N to 90S Never up Never up
68P/Klemola 14.0 bright 86N to 90S Best morning 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

May. 30, 2019

Comet inspires chemistry for making breathable oxygen on Mars

Researchers have demonstrated a new reaction for generating oxygen that could help humans explore the universe and perhaps even fight climate change at home.


May. 25, 2019

Comet Provides New Clues to Origins of Earth's Oceans

The mystery of why Earth has so much water, allowing our "blue marble" to support an astounding array of life, is clearer with new research into comets. Comets are like snowballs of rock, dust, ice, and other frozen chemicals that vaporize as they get closer to the Sun, producing the tails seen in images. A new study reveals that the water in many comets may share a common origin with Earth's oceans, reinforcing the idea that comets played a key role in bringing water to our planet billions of years ago.


May. 25, 2019

A family of comets reopens the debate about the origin of Earth's water

Researchers have found that one family of comets, the hyperactive comets, contains water similar to terrestrial water.


May. 23, 2019

Three exocomets discovered around the star Beta Pictoris

Three extrasolar comets have been discovered around the star Beta Pictoris, 63 light years away, by the University of Innsbruck. Analysis of data from the current NASA mission TESS by Sebastian Zieba and Konstanze Zwintz from the Institute for Astro- and Particle Physics, together with colleagues from Leiden University and the University of Warwick has revealed the extrasolar objects.


May. 15, 2019

New Comet C/2019 J1 (Lemmon)

CBET 4625 & MPEC 2019-J122, issued on 2019, May 12, announce the discovery of a comet (magnitude ~17.5) in the course of the "Mt. Lemmon Survey" (G96), in images taken on 2019, May 04 with a 1.5-m reflector + 10K CCD. This object was reported as a comet by R. A. Kowalski and D. Rankin (G96, May 4). The new comet has been designated C/2019 J1 (Lemmon).