Latest image

Comet C/2018 Y1 (Iwamoto)
Image of comet C/2018 Y1 (Iwamoto), obtained on 2019 Feb. 25 (19h39-20h18UT) with 15-cm, f/6 Maksutov-Cassegrain astrograph and Canon EOS 6D DSLR. Exposure time was 13x180 seconds at ISO 3200.
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 239000 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) (Mar 24, 2019).

Type  Comet name  Obs date       Mag   App  T  Pow   Dia   DC  Tail PA  Observer
  V      2018Y1   2019 03 23.83   9.8   10.0B   20    5    3            WAR01
  V      2018Y1   2019 03 23.81  10.2   18.5L   73    2.3  2            KWI  
  C      2017T2   2019 03 23.11  15.0   51.0Y a 60    0.3  3            BUIaa
  V      2018Y1   2019 03 22.82   9.6   30.0L   63    5    2            HAR11
  V      2018Y1   2019 03 22.81   9.9   19.8L   49    5    1/           HAR11
  C      2018A3   2019 03 21.97  16.3   20.0T A040                      SWAaa
  C      2018W2   2019 03 21.95  16.6   20.0T A000                      SWAaa
  C      2018W2   2019 03 17.51  16.2   61.0Y a180    0.25 4            BUIaa
  C      2018Y1   2019 03 16.91  10.7   20.0T a720    5.1               SWAaa
  C    60         2019 03 13.02  13.3   50.0T a 60    0.3  3   18.3m298 PAUaa
  V      2018Y1   2019 03 12.94   9.5   18.5L   73    4    2/           KWI  
  C      2016R2   2019 03 11.97  14.1   25.0T a360    0.7               WAR01
  C      2017K2   2019 03 11.97  16.1   25.0T a360    0.2               WAR01
  V      2018Y1   2019 03 11.96   8.7   10.0B   20    8    2/           GOI  
  C      2010U3   2019 03 11.92  14.0   25.0T a360    0.3               WAR01

Comet Observing Planner

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Current comet magnitudes and observable region

Comet                                   Mag   Trend   Observable          When visible
                                                                      45N              45S
C/2018 Y1 (Iwamoto)                     11.0  fade    90N to 56S  Best evening     Early evening   
C/2016 M1 (PANSTARRS)                   12.0  fade    38N to 90S  Never up         Never up        
46P/Wirtanen                            12.0  fade    90N to 52S  Best morning     Best morning    
123P/West-Hartley                       13.0  fade    90N to 60S  Best morning     Best morning    
29P/Schwassmann-Wachmann                13.5  steady  90N to 84S  Poor elongation  Poor elongation 
C/2017 M4 (ATLAS)                       13.5  bright  64N to 90S  Early evening    Best morning    
78P/Gehrels                             13.5  steady  90N to 80S  Early evening    Early evening   
38P/Stephan-Oterma                      13.5  fade    90N to 47S  Best morning     Best morning    
64P/Swift-Gehrels                       13.5  fade    90N to 66S  Best evening     Evening         
C/2018 L2 (ATLAS)                       14.0  fade    90N to 48S  Evening          Early evening   
60P/Tsuchinshan                         14.0  fade    85N 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.