Update 1. 1. 2025 A new comet was spotted on the night of 24–25 December 2024 by scientist Martin Mašek from the Institute of Physics over the western horizon in Argentina. He operated the telescope online from Liberec (city in the Czech Republic). This is the first Czech discovery of a comet where the observer was not physically present in the observatory, and the first Czech discovery from the southern hemisphere. The comet will not appear above our horizon until late February or early March.
Martin Mašek unwrapped his presents on Christmas Eve and then, as he does every evening, sat down at his computer, connected to the FRAM telescope in Argentina and looked at the band of evening sky over the western horizon. Around midnight, he was given an unexpected Christmas present when he spotted an unknown object – a comet C/2024 Y1 (Mašek).
This is the first comet discovered by a Czech operating a telescope in Argentina remotely while being in Liberec. The operator of the FRAM robotic telescope from the Institute of Physics of the Czech Academy of Sciences (FZÚ AV ČR) is systematically observing a strip of sky not very high above the western horizon in an area not searched through by large observatories.
"The brightness of the discovered comet is now about 3000 times fainter than the faintest star visible to the naked eye. The comet passed the closest point in its orbit around the Sun in late November and is now approaching Earth. It will not appear above our horizon until late February/March, when it passes from the constellation Eridanus to Orion, but it will have already dimmed considerably and its photographing will require large telescopes," explains Martin Mašek.
Artefact or real object?
When observing the sky, so-called synthetic tracking is done by using a special program called Tycho-Tracker to search for moving asteroids or comets and trying to stack a series of images on top of each other at different directions and speeds. This process, a conventional search, allows even less bright objects to be found.
"I wasn't 100 percent sure if it was an artefact or a real object, so I tried to track it down the next night. After I succeeded, I cautiously wrote to Daniel Green of CBAT (Central Bureau for Astronomical Telegrams) about the possible discovery of a new comet, with the understanding that I would make further, confirming observations. Unfortunately, on the third night, the weather was bad in Argentina, so I used another of FRAM's robotic telescopes, namely the 135mm telephoto lens located at the Cherenkov Telescope Array in Chile near Cerro Paranal Mountain, where the weather was clear, and even with such a small lens, the object was safely visible. I was confident enough to send my observations to the Minor Planet Center," says Martin Mašek.
Information about the possible new comet subsequently appeared on the Possible comet confirmation page on the Minor Planet Center website. Over the next few days, a number of observers from Australia and Chile sent in their own observations confirming the existence of the object, and its orbit is now being refined. On the night of 30 December, the Danish 1.54-metre telescope in Chile, to which Czech astronomers (Hana Kučáková, AÚ MFF UK, and Kamil Hornoch, ASÚ AV ČR) also have access, focused on the comet and took images that show the comet and its path between the stars very clearly. The official naming of celestial bodies is administered by the International Astronomical Union and comets are named after their discoverers according to these rules.
In total, FZU operates five FRAM (Photometric Robotic Atmospheric Monitor) robotic telescopes, which are primarily used for atmospheric calibration at global astroparticle observatories. Two FRAMs are operating in Argentina at the Pierre Auger Observatory, which focuses on detecting the most energetic cosmic rays. Three FRAMs are operating at the Cherenkov Telescope Array Observatory, with two telescopes in Chile and one in the Canary Islands. FRAMs monitor the instantaneous state of the Earth's atmosphere, in particular measuring atmospheric extinctions (the dimming of light from distant stars), and in their spare time they carry out a complementary astronomical programme (e.g. monitoring variable stars, comets or dangerous near-Earth asteroids).
Good to know:
Five recent comet discoveries by Czechs:
2000 - 196P/Tichý (Kleť, Miloš Tichý)
1991 - 124P/Mrkos (Kleť, Antonín Mrkos)
1984 - 143P/Kowal-Mrkos (Kleť, Antonín Mrkos)
1983 - 134P/Kowal-Vávrová (Kleť, Zdeňka Vávrová)
1975 - 76P/West-Kohoutek-Ikemura (Hamburg-Bergedorf, Luboš Kohoutek)
In 2024, 60 new comets have been discovered and confirmed so far. Most of them have been discovered by large robotic surveys that focus on finding dangerous near-Earth asteroids (e.g. ATLAS, Catalina, PANSTARRS).