Latest image

Comet C/2015 O1 (PANSTARRS)
False color unfiltered image of comet C/2015 O1 (PANSTARRS), obtained on 2018 Apr. 8 (1h13-1h23UT) with 60-cm, f/3.3 Deltagraph. Exposure time was 8x60s.
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 235000 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/2017 S3 (PANSTARRS) (Aug 14, 2018).

Type  Comet name  Obs date       Mag   App  T  Pow   Dia   DC  Tail PA  Observer
  V    21         2018 08 13.99   7.5    5.0B    7    9    5   45.0m265 KAR02
  V      2017M4   2018 08 13.93  14.3   30.5L  214    0.5  3            KAR02
  C    21         2018 08 13.88   8.4   28.0T A973    8                 JAMaa
  V    21         2018 08 13.84   7.8    8.0B   20    7    4            CAM03
  V    21         2018 08 13.84   7.9   80.0B   20                      JAKaa
  V    66         2018 08 13.82  13.9   40.6L  165    1    2            CAM03
  V   364         2018 08 13.81  13.3   40.6L   76    1    5            CAM03
  V    38         2018 08 13.80  13.8   40.6L  165    1    3            CAM03
  V    29         2018 08 13.79  14.0   40.6L  266    1.5  2            CAM03
  V    48         2018 08 13.78  12.5   40.6L   76    1    5            CAM03
  V      2018L2   2018 08 13.48  14.0   40.6L  165    1    3            CAM03
  V      2017M4   2018 08 13.47  14.0   40.6L  266    0.7  4            CAM03
  V      2018N1   2018 08 13.46  10.0   40.6L   76    6    1            CAM03
  V      2016M1   2018 08 13.45   9.0    8.0R   36    5    5            CAM03
  V      2018N1   2018 08 13.38  10.2   25.0L   39    6.4  3            WYA  

Comet Observing Planner

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Current comet magnitudes and observable region

Comet                               Mag   Trend   Observable         When visible
                                                                  45N            45S
C/2017 S3 (PANSTARRS)                2.5  steady  90N to 85S  Poor elongation Poor elongation
21P/Giacobini-Zinner                 8.0  bright  90N to 25S  All night      Never up      
C/2016 M1 (PANSTARRS)                9.0  fade    33N to 90S  Never up       Never up      
C/2017 T3 (ATLAS)                    9.5  fade    62N to 90S  Early evening  Evening       
C/2018 N1 (NEOWISE)                 10.5  fade    74N to 90S  Evening        Best evening  
C/2016 R2 (PANSTARRS)               12.0  fade    90N to 38S  All night      Never up      
48P/Johnson                         12.5  steady  66N to 90S  Best morning   Best morning  
C/2016 N6 (PANSTARRS)               12.5  steady  90N to 66S  Poor elongation Poor elongation
P/2013 R3-A (Catalina-PANSTARRS)    13.0  steady  72N to 90S  Best morning   Best morning  
P/2013 R3-B (Catalina-PANSTARRS)    13.0  steady  72N to 90S  Best morning   Best morning  
364P/PANSTARRS                      13.5  fade    55N to 90S  Early evening  Best morning  
37P/Forbes                          13.5  fade    90N to 84S  Best morning   Best morning  
66P/du Toit                         13.5  fade    75N to 90S  Best morning   Best morning  
38P/Stephan-Oterma                  13.5  bright  90N to 85S  Early evening  Early evening 
C/2017 M4 (ATLAS)                   14.0  steady  90N to 62S  Best evening   Evening       
29P/Schwassmann-Wachmann            14.0  steady  90N to 88S  Best morning   Best morning  
P/2010 H2 (Vales)                   14.0  fade    67N to 90S  Evening        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

Aug. 10, 2018

The cautionary tail of Comet Swift–Tuttle

Comet Swift–Tuttle, formally 109P/Swift–Tuttle, is an enormous, icy comet on a 133 year orbit around the Sun, and the reason for the spectacular annual Perseids meteor showers on Earth.


Jul. 18, 2018

New Comet: C/2018 N2 (ASASSN)

MPEC 2018-O01, issued on 2018, July 16, announces the discovery of a comet (magnitude ~16.1) in the course of the "All-Sky Automated Survey for Supernovae" (ASASSN) program, in images taken 2018 July 7-11 with the 14-cm "Cassius" survey telescope at Cerro Tololo. The new comet has been designated C/2018 N2 (ASASSN).


Jul. 09, 2018

Molecular oxygen in comet's atmosphere not created on its surface

Scientists have found that molecular oxygen around comet 67P is not produced on its surface, as some suggested, but may be from its body.


Jun. 29, 2018

Chasing 'Oumuamua

The interstellar object 'Oumuamua perplexed scientists in October 2017 as it whipped past Earth at an unusually high speed. This mysterious visitor is the first object ever seen in our solar system that is known to have originated elsewhere.


Jun. 29, 2018

Our Solar System's First Known Interstellar Object Gets Unexpected Speed Boost

Using observations from NASA's Hubble Space Telescope and ground-based observatories, an international team of scientists has confirmed 'Oumuamua (oh-MOO-ah-MOO-ah), the first known interstellar object to travel through our solar system, got an unexpected boost in speed and shift in trajectory as it passed through the inner solar system last year.