Comet C/2011 KP36 (Spacewatch)
False color image of comet C/2011 KP36 (Spacewatch), obtained on 2016 Jun. 29 (1h13-1h32UT) with 60-cm, f/3.3 Deltagraph. Exposure time 5x120s. Copyright © 2016 by H. Mikuz, Crni Vrh Observatory.

Welcome to COBS!

Comet Observation database (COBS) was developed in 2010 and is maintained by Crni Vrh Observatory. It is a unique service offering comet observers to submit, display and analyse comet data in a single location and is opened to comet observers worldwide. Registered observers may submit the observations using a simple web-based form which will store their observations into an SQL database and display them in ICQ format.

Data stored in COBS database is freely available to everyone with respect to our data usage policy, and can be analysed with COBS online tools or exported and further used in other analysis software and publications.

Database currently contains more than 225000 comet observations of more than 1100 different comets and represents the largest available database of comet observations.

Amateur comet observers can make a useful contribution to science by observing comets and submitting their observations to the COBS, as the professional astronomers do not have the time nor the telescopes needed to gather such data. We encourage comet observers worldwide to submit their observations and contribute to the COBS database.

Light-curve of Comet C/2015 V2 (Johnson) (Oct 18, 2016).

Recent observations

Type  Comet name  Obs date       Mag     Dia   DC  Tail     Observer
  C      2011KP36 2016 10 23.22  13.7     1.4               RAMaa
  C    56         2016 10 23.22  15.3     0.3               RAMaa
  C      2016N4   2016 10 23.21  15.6:    0.3               RAMaa
  C      2016R2   2016 10 20.53  15.3     2.5               LEHaa
  C      2015O1   2016 10 20.07  15.8     0.3               RAMaa
  C      2015V2   2016 10 19.49  13.7     1.5      0.03 307 LEHaa
  C      2015V2   2016 10 19.49  13.6     1.6      0.03 305 LEHaa
  V    29         2016 10 19.42 [14.8                       WYA  
  V      2011KP36 2016 10 19.42  13.2     1.7  3            WYA  
  V   237         2016 10 19.41  12.5     1    4            WYA  
  V      2011KP36 2016 10 18.41  13.1     1.7  2/           WYA  
  V   237         2016 10 18.40  12.3     0.5  4            WYA  
  V    29         2016 10 18.40 [14.5                       WYA  
  C      2015V2   2016 10 17.50  14.0     0.8      0.03 307 LEHaa
  C      2015V2   2016 10 16.49  13.8     1.5      0.03 309 LEHaa


Comet Observing Planner

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Current comet magnitudes (October 12)

Comet                     Magnitude   Trend    Observable     When visible
144P/Kushida                  10.5    fade     60 N to 20 S   early morning
43P/Wolf-Harrington           10.5    fade     55 N to 30 S   early morning
237P/LINEAR                   11      steady   20 N to 50 S   early evening
81P/Wild                      11.5    fade     Poor elongation
Johnson (2015 V2)             12      bright   80 N to 35 N   morning
PanSTARRS (2013 X1)           12      fade     Poor elongation
9P/Tempel                     12.5    fade     15 N to 65 S   evening
PanSTARRS (2014 S2)           12.5    fade     Conjunction
Spacewatch (2011 KP36)        12.5    steady   60 N to 65 S   best midnight
29P/Schwassmann-Wachmann      13 ?    varies   40 N to 70 S   evening
LINEAR (2016 A8)              13.5    fade     50 N to 55 S   evening
Catalina (2013 US10)         [13.5    fade     80 N to  0 N   best morning
226P/Pigott-LINEAR-Kowalski  [14 ?    steady   80 N to 50 S   best morning

List of comets maintained by Jonathan Shanklin at

Latest news

Oct. 19, 2016

Astronomers predict possible birthplace of Rosetta-probed comet 67P

When the Rosetta spacecraft successfully touched down on comet 67P/Churyumov-Gerasimenko on September 30, 2016, the news was shared globally via Twitter in dozens of languages. Citizens the world over were engaged by the astronomical achievement, and now experts are eager to learn as much as possible about the critically important celestial body of ice.


Oct. 18, 2016

Klim Churyumov (1937-2016)

We were saddened to learn the news yesterday that Klim Churyumov, who discovered Rosetta's comet together with Svetlana Gerasimenko in 1969, has passed away.


Oct. 16, 2016

A note to CCD observers - kphot review

It’s been several years that a new method of processing CCD observations was announced by german astronomer Uwe Pilz. The method was a promising way for amateur astronomers, to generate a visual equivalent magnitude using a CCD measures with a very simple way of processing. Now after several years, there were several observers which were using this method, one of most active was Kevin Hills from United Kingdom. The huge amount of his observations made possible a deep comparative analysis of this method with visual and classic CCD magnitudes.


Oct. 08, 2016

CometWatch from Kepler

During the last month of Rosetta's operations at Comet 67P/Churyumov-Gerasimenko, it was no longer possible to observe the comet with telescopes on Earth because it was not far from the Sun's position in the sky and therefore not visible in the night-time. Fortunately, NASA's Kepler space observatory stepped in, taking images of the comet every 30 minutes from 7 to 20 September, providing important context to Rosetta's in situ measurements.


Oct. 08, 2016

Loss of signal confirmation

Spacecraft Operations Manager Sylvain Lodiot confirms loss of signal (LOS) and end of Rosetta operations at 13:19 CEST, 30 September 2016, via the voice loop in the Main Control Room at ESA's space operations centre, Darmstadt, Germany.