Don’t Blink: New Comet SWAN Skims Wyoming Skies Through October

Got binoculars? You’ll want them. A newly discovered visitor—Comet C/2025 R2 (SWAN) — is sliding along Wyoming’s evening sky for the next few weeks, and while it isn’t a showstopper, it might be the last decent comet we see until Halley’s returns in July 2061.

Spotted by an amateur astronomer on Sept. 11, SWAN currently shines around magnitude 7 — just beyond naked-eye range for most places but easy pickings with binoculars or a small scope.

“Find it while you can,” said Max Gilbraith, planetarium coordinator at the University of Wyoming. “It’s hard to say, but we could have a drought until Halley’s Comet comes back in 2061.”

Part of the buzz is where SWAN likely comes from. Gilbraith says astronomers think this one originated outside our solar system.

“It’s the third time we’ve ever discovered something coming from outside of the solar system,” he said, noting a recent run of such finds. “If you ran the odds, the SWAN Comet might be once in a lifetime, but we’ve seen three of these comets in eight years.”

Early images show a real tail — Australian comet watcher Michael Mattiazzo photographed a streak about 2.5 degrees long, roughly five Moon-widths. Don’t expect that every night from Wyoming, though. Right now the comet hugs the western horizon after dusk, which means you’re peering through a thick stack of atmosphere that dims the view.

“The viewing angle will get better as we get into October, so it’ll be easier to see,” Gilbraith said.

Here’s the rough sky path: SWAN drifts through Libra around Sept. 28, slides into Scorpius by Oct. 10, and heads toward the Milky Way’s neighborhood near Sagittarius later in the month. It makes its closest pass to Earth on Oct. 20 — handy timing, with a nearly new Moon for darker skies. From a truly dark site, you might tease it out without optics if it brightens toward magnitude ~5.8, but plan on binoculars to be safe. Look low in the west after twilight; being near Mars at times is an extra pointer.

Temper expectations. SWAN won’t rival the greats — think modest fuzzball with a stubby tail, not a billboard across the sky. But in a stretch that’s been surprisingly stingy with bright comets, it’s still a worthy target.

“The beautiful comets that put on a spectacular show are still a once-in-a-decade occurrence,” Gilbraith said. “There’s lots of fun stuff to look at with binoculars, and while you’re scanning around, you might spot this little comet with a tail.”

The original story by Andrew Rossi for Cowboy State Daily.