Two comets will be visible in Autumn 2026

This autumn, astronomy enthusiasts will be able to observe two comets—220P/McNaught and 161P/Hartley-IRAS—in the night sky. Observations will require fairly large amateur telescopes, according to Mikhail Maslov, lead engineer at the Vega Observatory of Novosibirsk State University.

Comet 220P/McNaught – in September

The first to become available will be comet 220P/McNaught. It will be observable throughout September. The object's brightness will gradually decrease from magnitude 10 to 12 over the course of the month. The best time for observation is the second half of the night. The comet will be located on the border between the constellations Taurus and Cetus.

Comet 161P/Hartley-IRAS – in October and November

The second comet, 161P/Hartley-IRAS, will appear in the sky in October and November. In appearance, it is typical of short-period comets: a green, spherical coma and a small, faint tail. Its brightness is expected to be around magnitude 10–11.

The best time to observe it is in the evening, before midnight. In October, the comet will pass through the constellations Aquarius, Equuleus, and Delphinus. In November, it will move into the constellations Aquila and Sagitta.

The orbital period of 161P/Hartley-IRAS around the Sun is 21 years. The comet was last observed in 2005.

In Brief

In autumn 2026, two comets will be visible through large amateur telescopes. 220P/McNaught will be available in September on the border of Taurus and Cetus, with a brightness of magnitude 10–12. 161P/Hartley-IRAS will appear in October–November with a brightness of magnitude 10–11 and will pass through the constellations Aquarius, Equuleus, Delphinus, Aquila, and Sagitta. Its orbital period is 21 years.