A newly discovered comet, C/2025 A6 (Lemmon), first spotted early this year, is set to make its closest approach to Earth on October 21st, at a distance of less than 90 million kilometers. This information was released by the Laboratory of Solar Astronomy at the Space Research Institute (IKI) of the Russian Academy of Sciences.
The comet is brightening more rapidly than initially predicted, and within the next 10-14 days, it is expected to reach a magnitude of 5. This luminosity will make it visible through binoculars across Russia`s night sky.
Currently, Comet Lemmon is approximately 200 million kilometers from Earth, but this distance is diminishing significantly, by about 5 million kilometers daily. By October 3rd, it will be within 150 million kilometers, and on October 21st, it will achieve its minimum distance from Earth, under 90 million kilometers.
The comet`s peak brightness is anticipated in late October to early November. During this period, calculations suggest it will reach magnitudes between 2 and 4, making it potentially observable to the naked eye. Scientists also noted that the comet is currently moving swiftly across the sky towards the constellation Ursa Major (the Big Dipper).
By mid-October, it should be visible near Ursa Major even with basic optical instruments. Towards the end of October, at its brightest, it will shift into the constellations Serpens (the Serpent) and Ophiuchus (the Serpent-bearer), where it is expected to be visible without optical aid after sunset.
Published: September 23, 2025
