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 stores the observations in an SQL database and stores them in ICQ format. Observations may be queried and plotted in the website or exported for further processing, analysis and publication. The database currently contains more than 292500 comet observations of more than 1700 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 image

Unfiltered false color image of comet C/2025 A6 (Lemmon), obtained on 2025 Sep. 4 (2h32-2h45UT) UT with 60-cm, f/3.3 Deltagraph telescope and CMO. Exposure time was 10 minutes (10x60 seconds). Image scale is 1.56 arc sec/pixel. Copyright © 2025 by H. Mikuz, Crni Vrh Observatory.

Comets visible today at Crni Vrh Observatory

Comet Mag T Source Best time Const Obs Chart Comet PK Comet MPC Type MPC name

Location: Crni Vrh Observatory
Latitude: 45.94583; longitude: 14.07111; elevation: 726.0
Limiting mag: 15; Min altitude: 0; Min solar elong: 0; Min moon elong: 0
All times are in UTC

Comet finding charts provided by Dominic Ford: https://in-the-sky.org/

Lightcurve of comet C/2024 E1 (Wierzchos)

Recent observations

Type Comet Obs date Meth Mag T App P Dia DC Tail Tail unit PA User Pk

Latest news

NASA’s Webb Space Telescope Reveals Secrets of Interstellar Comet 3I/ATLAS
September 02, 2025

Webb, Hubble, and SPHEREx are joining forces to study the interstellar comet 3I/ATLAS, revealing details about its structure and chemistry. The comet isn’t dangerous, but it’s offering scientists a rare chance to explore material from outside our solar system.

Our solar system has a new interstellar visitor: Meet 3I/ATLAS
August 30, 2025

Astronomers have spotted 3I/ATLAS, just the third interstellar object ever seen in our solar system. Bigger, faster, and possibly far older than ‘Oumuamua or Borisov, this icy traveler could help unlock clues about how other star systems formed billions of years ago.

Is 3I/ATLAS really a Comet?
August 27, 2025

The most intriguing mystery in astronomy today is the nature of interstellar object 3I/ATLAS. Most astronomers believe it is a comet. However, iconoclast Avi Loeb of Harvard University makes the case that it might be something else--like alien tech.

Hubble just snapped the clearest-ever picture of a rare interstellar comet
August 19, 2025

Hubble has taken the clearest image to date of the interstellar comet 3I/ATLAS, which is racing through our solar system at 130,000 miles per hour. Astronomers are using Hubble and other telescopes to better understand its icy nucleus and chemical composition.

This interstellar comet may be a frozen relic from before the Sun
July 13, 2025

A newly discovered comet, 3I/ATLAS, may be the most ancient visitor ever detected, potentially older than our solar system itself. Unlike previous interstellar objects, this ice-rich comet seems to originate from the thick disk of the Milky Way, a region filled with ancient stars. First spotted in July 2025, it’s already showing signs of activity and could help scientists understand more about galactic chemistry and the origins of planetary systems.