Due to its path and angularly small movement across the sky, it will offer virtually the same direction and height above the horizon almost continuously until the end of July - around 11 pm at about 10° above the northwestern horizon. It cannot be seen with the naked eye, but it can be seen with small telescopes, such as triads, as a blurred object travelling successively across the constellations of the Wozze, Rys, the Great Bear and the Little Lion in the coming months.

A small comet

The comet was discovered more than 209 years ago, namely on March 6th, 1815, by the famous German astronomer Heinrich Wilhelm Olbers (1758-1840), who made history with, among other things, the discovery of the large asteroids Pallas and Vesta in the main asteroid belt and is also the author of the "Olbers paradox", which shows the discrepancy between the observed darkness of the Universe despite the density of stars and other light sources in it. He found the comet in the constellation of Giraffe and confirmed his discovery a day later, on March 7th, 1815. In his observation diary he added only: "The comet is moving slowly to the north and east in the body of Perseus. It is small and has a poorly defined nucleus and a very pale transparent tail." It reached 5th magnitude that year, so it was just at the limit of visibility with the naked eye.

Returns through the eyes of great astronomers

Astronomers saw the comet again in 1887 and 1956, both times it did not reach any spectacular brightness. Nevertheless, it has gained attention, mainly due to the confirmation of its period, which is now about 70 years. It is thus classed among the Halley-type comets, whose periods are between 20 and 200 years. Interestingly, it has been discovered by a famous "comet hunter" on each of its subsequent returns. In 1887, it was first observed on 25th August by the famous American astronomer William Robert Brooks (1844-1921), co-discoverer of this year's comet 12P/Pons-Brooks. On its return in the 20th century, it was discovered for a change by the equally famous Czechoslovak astronomer Antonín Mrkos (1918-1996) on January 4th, 1956, just about five and a half months before its flyby (which occurred on June 19th, 1956). Prior to this year's flyby, the American astronomer Alan Hale (born 1958), co-discoverer of the remarkably bright Comet Hale-Bopp in 1995, was responsible for its first observation. Hale found Olbers' comet as early as 23rd of August 2023, using digital images from Las Cumbres Observatory.

Look out at dusk

Throughout June and July, the comet will move between the constellations of the Wozzy and the Big Dipper, its orbit relative to the Earth and Sun keeping it virtually always low in the sky above the northwestern horizon until the end of July. It will be viewable in late twilight before 11pm at around 15°, but will always be much lower in the dark. To observe it, therefore, it is necessary to find a place with a perfectly exposed north-western horizon, and in that direction there should be no large town for tens of kilometres at the chosen observation point. To locate it, it's a good idea to have a map showing its exact current position relative to the stars (available, for example, at The Sky Live). The comet will pass by on June 30th, 2024, reaching a maximum brightness of about magnitude 6.5 just one day later. At that time, the Moon will not be disturbing the evening sky, so the comet should be relatively easy to observe with small telescopes far from cities (if weather permits it, of course).

The comet will reappear in the sky in 2094, together with the equally interesting (and widely observed this year) comet 12P/Pons-Brooks. So it's definitely worth getting out the trier and, along with a map or mobile app, looking for this interesting comet, even if it's not one of the exceptionally bright ones.

Contact details:

Mgr. Petr Horálek

RNDr. Tomáš Gráf, Ph.D.

Suggested links: