Latest image

Comet 46P/Wirtanen
Image of periodic comet 46P/Wirtanen, obtained on 2019 Jan. 5 (20h41-21h11UT) with 15-cm, f/6 Maksutov-Cassegrain astrograph and Canon EOS 6D DSLR. Exposure time was 10x180 seconds at ISO 3200.
Copyright © 2018 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 238000 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 46P/Wirtanen (Jan 20, 2019).

Type  Comet name  Obs date       Mag   App  T  Pow   Dia   DC  Tail PA  Observer
  C      2017M4   2019 01 19.28  14.3   25.0T a720    0.8               MAS01
  C      2017M4   2019 01 19.27  13.9   25.0T a840    0.8               MAS01
  V    46         2019 01 19.24   7.0    5.0B    7   12    2            WAR01
  V      2018Y1   2019 01 19.24   9.5   20.0T   50    4    3            LAB02
  V    46         2019 01 18.75   7.6   10.5R   16    5                 PIL01
  C    21         2019 01 18.32  15.6   30.0C A620    0.5               MAS01
  C    21         2019 01 18.31  15.4   30.0C A620    0.5       0.3m335 MAS01
  V      2018Y1   2019 01 18.22   9.0   19.8L   59    5.5  2            HAR11
  V    46         2019 01 18.20   6.9    4.4B    8   28    2            HAR11
  V    46         2019 01 18.19   7.0   19.8L   37   20    3            HAR11
  V    46         2019 01 18.18   7.3    5.6B    8  &20    3            SCH04
  C    38         2019 01 16.95  11.7   25.4Y A010    2.9       3.8m250 BAMaa
  V    38         2019 01 16.89  10.1   25.4T   96    2.1  3            COLac
  V    46         2019 01 16.88   6.8    4.0B   10   38    3            COLac
  V      2016M1   2019 01 16.63  10.9   20.0L   48    2.4  4/           RAE  

Comet Observing Planner

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Current comet magnitudes and observable region

Comet                                   Mag   Trend   Observable          When visible
                                                                      45N              45S
46P/Wirtanen                             7.0  fade    90N to 32S  All night        Never up        
C/2018 Y1 (Iwamoto)                      9.0  bright  69N to 90S  Early evening    Best morning    
64P/Swift-Gehrels                       10.0  fade    90N to 62S  Best evening     Evening         
C/2018 L2 (ATLAS)                       11.0  fade    90N to 64S  Evening          Early evening   
38P/Stephan-Oterma                      11.5  fade    90N to 44S  All night        Never up        
C/2016 M1 (PANSTARRS)                   12.0  fade    10N to 90S  Never up         Never up        
C/2016 N6 (PANSTARRS)                   13.0  fade    68N to 90S  Best morning     Best morning    
78P/Gehrels                             13.5  steady  88N to 90S  Evening          Early evening   
29P/Schwassmann-Wachmann                13.5  steady  90N to 89S  Evening          Early evening   
C/2016 R2 (PANSTARRS)                   13.5  fade    90N to 49S  Best morning     Early evening   
C/2018 N2 (ASASSN)                      14.0  steady  61N to 90S  Evening          Best evening    
59P/Kearns-Kwee                         14.0  fade    90N to 67S  Best morning     Best morning    
C/2017 M4 (ATLAS)                       14.0  steady  76N to 90S  Early evening    Early evening   
C/2018 V1 (Machholz-Fujikawa-Iwamoto)   14.0  fade    63N to 90S  Poor elongation  Poor elongation 
123P/West-Hartley                       14.0  bright  90N to 61S  Best morning     Best morning    
C/2015 O1 (PANSTARRS)                   14.0  steady  90N to 48S  Best morning     Early evening   
60P/Tsuchinshan                         14.0  fade    86N to 90S  Best morning     Best morning    

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. 15, 2019

COBS Maintenance: Switch to hosted services

In the recent days, COBS website was moved to a new server.


Jan. 03, 2019

MU69 appears as a bi-lobed baby comet in latest New Horizons images

The tiny world 2014 MU69 is far behind New Horizons now and no longer visible to its cameras. Now, New Horizons’ task is to return its precious data to Earth. The process will take 20 months, but the best images should all arrive between now and the end of February. Some early ones have come down from the spacecraft in the hours since the flyby. These are not the best we will get, but they already show us much about MU69: this is probably what comets look like, before they become comets.


Dec. 21, 2018

New Comet C/2018 Y1 (Iwamoto)

CBET 4588 & MPEC 2018-Y52, issued on 2018, Dec. 20, announce the discovery of a comet (magnitude ~12) by M. Iwamoto (MPC code 872) in images taken on 2018 Dec 18.8. The new comet has been designated C/2018 Y1 (Iwamoto).


Dec. 21, 2018

Hubble Takes a Close Look at the Brightest Comet of the Year

On December 13th, NASA’s Hubble Space Telescope photographed comet 46P/Wirtanen, a periodic comet that orbits the Sun once every 5.4 years.


Dec. 21, 2018

Rosetta witnesses birth of baby bow shock around Comet

A new study reveals that, contrary to first impressions, Rosetta did detect signs of an infant bow shock at the comet it explored for two years – the first ever seen forming anywhere in the Solar System.