Latest image

Comet C/2018 Y1 (Iwamoto)
Image of comet C/2018 Y1 (Iwamoto), passing the open clusters M38 and NGC 1907 in Auriga. Obtained on 2019 Feb. 28 (21h40-22h47UT) with 15-cm, f/6 Maksutov-Cassegrain astrograph and Canon EOS 6D DSLR. Exposure time was 66 minutes 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 240000 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) (Apr 23, 2019).

Type  Comet name  Obs date       Mag   App  T  Pow   Dia   DC  Tail PA  Observer
  V   123         2019 04 22.89  13.7   53.1L  155    1.1  3            HAR11
  C    38         2019 04 22.14  14.6   10.6R a180    2.1       6.9m265 RAMaa
  C    46         2019 04 22.13  13.6   10.5R a180    6                 RAMaa
  C    46         2019 04 21.91  15.3   10.0R A742    1.3               FRIaa
  C      2015O1   2019 04 21.88  15.6   10.0R B164    1.6               FRIaa
  V   123         2019 04 21.86  13.1   30.0L   96    1    3            HAR11
  C      2018Y1   2019 04 21.84  12.3   10.0R A622    3.7               FRIaa
  C      2018L2   2019 04 16.10  14.7   10.0R A141    0.8               FRIaa
  C      2016R2   2019 04 16.05  15.4   10.0R A983    1.3               FRIaa
  C      2010U3   2019 04 15.97  16.4   10.0R E168    1.2               FRIaa
  C    64         2019 04 15.88  15.7   10.0R A983    1.2               FRIaa
  C      2018Y1   2019 04 15.84  12.1   10.0R A742    4.8               FRIaa
  V   123         2019 04 09.90  13.8   53.1L  155    0.8  3            HAR11
  C      2018W2   2019 04 08.90  15.9   20.0L C480    0.8      0.01  75 LEHaa
  V   123         2019 04 08.88  12.5   53.1L  155    1    3            HAR11

Comet Observing Planner

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Current comet magnitudes and observable region

Comet                                   Mag   Trend   Observable          When visible
                                                                      45N              45S
C/2016 M1 (PANSTARRS)                   12.0  fade    48N to 90S  Early evening    Best evening    
123P/West-Hartley                       13.0  fade    90N to 65S  Best morning     Best evening    
C/2018 Y1 (Iwamoto)                     13.0  fade    90N to 56S  Evening          Early evening   
29P/Schwassmann-Wachmann                13.5  steady  90N to 81S  Early evening    Early evening   
C/2017 M4 (ATLAS)                       13.5  steady  55N to 90S  Best morning     Best morning    
C/2017 T2 (PANSTARRS)                   13.5  bright  90N to 82S  Early evening    Early evening   
78P/Gehrels                             14.0  steady  90N to 75S  Poor elongation  Poor elongation 
C/2018 N2 (ASASSN)                      14.0  steady  84N to 90S  Poor elongation  Poor elongation 

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

Apr. 16, 2019

Tiny fragment of a comet found inside a meteorite

Astronomers have made a surprising discovery that gives clues to how solar system formed.


Apr. 02, 2019

Comets & Asteroids - Summary for Jan & Feb 2019

During the 2-month period January through February 2019, 14 new comets were discovered. Moreover inner main-belt minor planet (6478) GAULT developed a lengthening tail or trail.


Mar. 29, 2019

Hubble watches spun-up asteroid coming apart

A small asteroid has been caught in the process of spinning so fast it's throwing off material, according to new data.


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.