Latest image

C/2020 R4 (ATLAS)
Image of comet C/2020 R4 (ATLAS), obtained on 2021 May 10 (20h24-20h49UT) with 19-cm, f/4 Flat Field Camera and Canon EOS 700D DSLR. Exposure time was 23x60 seconds at ISO 3200. Total exposure time 23 minutes.
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 259000 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/2020 T2 (Palomar) (Jun 18, 2021).

Type Comet name Obs date Mag App T Pow Dia DC Tail PA Obs
C C/2017 K2 2021 06 17.01 13.2 10.0 R B100 2.7 0.4m 220 DEK01
C C/2020 J1 2021 06 16.98 13.6 10.0 R A350 1.3 DEK01
V C/2017 K2 2021 06 16.97 12.7 29.8 L 132 0.7 3 HAR11
C C/2020 T2 2021 06 16.96 10.7 10.0 R A800 6.7 9.7m 118 DEK01
C C/2021 A1 2021 06 16.93 16.9 10.0 R C150 0.5 DEK01
V C/2020 T2 2021 06 16.92 10.4 25.0 L 60 2 d3/ FIL04
V C/2017 K2 2021 06 16.09 14.5 25.0 L 120 TRAab
C C/2017 K2 2021 06 16.05 12.8 10.0 R B100 2 DEK01
C C/2020 T2 2021 06 15.96 10.6 10.0 R A800 6.7 8.0m 127 DEK01
C C/2021 A1 2021 06 15.93 16.7 10.0 R C150 0.5 DEK01
C 7P 2021 06 15.83 10.5 10.6 R a600 17.5 8.5m 260 HER02
C 15P 2021 06 15.81 11.6 51.0 Y a120 4.5 4 2.5m 243 CHAab
C 7P 2021 06 15.81 11.2 51.0 Y a120 6 6.0m 264 CHAab
V C/2017 K2 2021 06 15.50 13.5 40.0 L 108 1.3 4 WYA
V C/2020 J1 2021 06 15.48 13.6 40.0 L 182 1.8 6 WYA
V C/2019 F1 2021 06 15.47 14.7 40.0 L 182 0.6 6 WYA
V C/2020 T2 2021 06 15.46 10.6 40.0 L 59 4 6 8.0m 118 WYA
C C/2020 S3 2021 06 15.45 15.8 61.0 Y a480 1.7 > 0.25 260 HER02
C C/2020 S3 2021 06 15.45 17.0 61.0 Y a480 0.4 HER02
V 7P 2021 06 15.22 11.2 22.0 L 160 3 3/ GOI

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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
45N
Visiblity
45S
C/2020 T2 (Palomar) 10.5 steady 90N to 75S Best morning Best evening
6P/dArrest 11.0 bright 90N to 73S Best morning Best morning
7P/Pons-Winnecke 11.5 fade 66N to 90S Early evening Best morning
C/2019 L3 (ATLAS) 12.0 bright 90N to 40S All night Never up
C/2020 X3 (SOHO) 12.5 fade 68N to 90S Evening Best evening
15P/Finlay 12.5 bright 90N to 83S Early evening Early evening
C/2020 J1 (SONEAR) 13.0 fade 73N to 90S Best evening Best evening
C/2017 K2 (PANSTARRS) 13.0 bright 90N to 47S Best morning Best morning
8P/Tuttle 13.0 bright 90N to 48S Early evening Early evening
P/2013 PA104 (PANSTARRS) 13.5 fade 84N to 90S Best evening Best evening
246P/NEAT 13.5 steady 59N to 90S Best morning Best morning
4P/Faye 13.5 bright 90N to 78S Early evening Early evening
29P/Schwassmann-Wachmann 14.0 steady 90N to 61S Early evening Early evening
C/2019 T4 (ATLAS) 14.0 steady 66N to 90S Early evening Evening
342P/SOHO 14.0 bright 56N to 90S Early evening Best morning
C/2020 K5 (PANSTARRS) 14.0 fade 53N to 90S Early 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

Jun. 15, 2021

New Comet C/2021 K2 (MASTER)

CBET 4975 & MPEC 2021-L89, issued on 2021, June 09, announce the discovery of a new comet (magnitude ~19.0) on CCD images taken on May 23.0 UT with the "Mobile Astronomical System of the Telescope-Robots" (MASTER) auto-detection system (double 0.40-m f/2.5 reflector) at the South African Astronomical Observatory. The object was reported by MASTER as a new NEO candidate and has been found to show cometary activity by CCD astrometrists elsewhere. The new comet has been designated C/2021 K2 (MASTER).

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Jun. 05, 2021

New Comet C/2021 J1 (Maury-Attard)

CBET 4972 & MPEC 2021-L11, issued on 2021, June 02, announce the discovery of a new comet (magnitude ~19.0) on CCD images taken by A. Maury and G. Attard on May 09.3 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 C/2021 J1 (Maury-Attard). This is the first amateur comet discovery of 2021. It is also the first comet ever discovered using the synthetic tracking technique (using TYCHO software).

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May. 31, 2021

New Comet C/2021 K1 (ATLAS)

CBET 4968 & MPEC 2021-K89, issued on 2021, May 27, announce the discovery of a new comet (magnitude ~17.0) on CCD images taken on May 14.5 UT with the 0.5-m reflector + CCD in the course of the ATLAS-HKO (T05) survey. The object was originally found by Peter Veres of Minor Planet Center (MPC) as unusually bright among the MPC's isolated tracklet file (ITF) and linked to the detections from May 22 (F51) and May 14 (T08). A review of the ATLAS images revealed the cometary nature of this object.

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May. 09, 2021

New Reference catalog keys

New reference catalog keys were assigned for GAIA DR catalog and APASS catalog.

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May. 07, 2021

New Comet C/2021 E3 (ZTF)

CBET xxxx & MPEC 2021-J71 , issued on 2021, May 06, announce the discovery of an apparently asteroidal object (magnitude ~19.5) on CCD images taken on March 09.5 UT with the 1.2-m Schmidt telescope at Palomar in the course of the "Zwicky Transient Facility" (ZTF) search program. This object has been found to show cometary appearance by CCD astrometrists elsewhere. The new comet has been designated C/2021 E3 (ZTF).

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