Two new comets will light up the October sky: Lemmon and SWAN promise a show that’s hard to beat
For centuries, comets have fascinated humanity with their mysterious beauty. This year 2025 is no exception: two icy visitors are approaching to give us a show visible from Earth. One is already increasing its brightness every night; Both serve as a reminder that the sky still holds unpredictable wonders.
The comet Lemmon and its growing brightness
Discovered in January by Carson Fuls in the observatory, the Lemmon comet has been following an eccentric orbit that brings it back after more than a thousand years. After an encounter with Jupiter, its trajectory was shortened by two centuries, and now it is getting ready to pass 101 million km from Earth on October 21.
The SWAN comet, an unexpected discovery
The second protagonist is the SWAN comet, detected just days ago by the SWAN instrument. Although it won’t reach the visibility of Lemmon, it will still offer a remarkable show with binoculars or small telescopes, displaying a diffuse coma and a fine, extended ionic tail.
A date with the unpredictable
Experts warn that comets are famous for their unpredictable nature: sometimes they shine brighter than expected, other times they disintegrate prematurely. As David H. Levy wrote, “comets are like cats: they have tails and do whatever they please.” What is clear is that October offers a unique opportunity to observe not one, but two icy travelers, reminding us that the night sky can still surprise us.
