Viewing Comet C/2025 R2 SWAN in October Skies

What an October it has been for comets! News outlets have been buzzing about three notable visitors: Comet SWAN, Comet Lemmon, and the intriguing interstellar object 3I/ATLAS, which has stirred up quite a bit of media chatter from people wondering if it’s an alien spacecraft (spoiler: it’s not!).

Unlike most comets spotted by Earth-based telescopes, C/2025 R2 (SWAN) was discovered by an instrument that wasn’t even built to look for them. In September 2025, amateur astronomer Vladimir Bezugly found the comet scanning images from the SWAN instrument aboard the SOHO spacecraft, a satellite that watches the Sun, not the stars. Check out the brief on the Central Bureau for Astronomical Telegrams for the full story.

The comet made its closest approach to Earth on October 20, 2025, passing at a distance of about 0.26 astronomical units — roughly 39 million kilometers (24 million miles) away. It will continue moving northward in the sky, crossing the celestial equator on November 3, 2025.

For those interested in catching a glimpse of the comet, I suggest reading theskylive.com or space.com.

My Observations

The other morning, I was up before dawn to capture Comet Lemmon in the eastern sky. This evening, my attention has shifted westward after sunset to take in the sight of C/2025 R2 (SWAN) in the constellation Serpens. My photos don’t do the comet justice, as there are so many great ones by astrophotographers, including those shared on EarthSky. Still, there’s something special to watching a comet in person.

I was also able to spot the comet through my 25×70 binoculars, but from my suburban vantage point, with light clouds drifting in from the Gulf, it appeared only as a faint smudge of its coma.