Newly-discovered comet is glowing green, only visible once every 22,000 years

The newest comet to create a buzz among sky watchers was spotted recently, and it will be coming closer to Earth in October – possibly giving us a better look at this once-in-a-lifetime visitor from the outer reaches of our solar system.

The comet’s official name is C/2025 R2 (SWAN). Early photos show it has a very long gas tail, and a head that’s glowing green. While it can’t be seen with the eyes only right now, it’s expected to get brighter as we get into October, according to EarthSky.

How it was found

In sharing a photo of the green comet, NASA said C/2025 R2 (SWAN) was first spotted on Sept. 11 when it was on a very close approach to the sun. It was seen in images taken by the SWAN instrument on the SOHO spacecraft.

Initially, it was hard to see because it was caught up in the sun’s glare, but a few days later better pictures were taken when it was near the star Spica, which sits in the Virgo constellation, NASA said.

NASA has tracked this comet’s orbit path and estimates it takes more than 22,500 years for the comet C/2025 R2 (SWAN) to complete its orbit around the sun.

Viewing tips

While our Northern Hemisphere is not the best viewing position for this comet, skywatchers are hoping we’ll get a much better show from it soon.

The next best chance to see it will be around Oct. 2. You’ll want to use a pair of binoculars after sunset, and look to the southwest part of the sky.

“Near the western horizon after sunset and slightly easier to see in binoculars … this comet SWAN will pass near Zubenelgenubi, alpha star of Libra, on October 2,” NASA said. “C/2025 R2 (SWAN) is scheduled to make its closest approach to our fair planet around October 20.”

Keep that Oct. 19-20 date in your calendar. Right around that time, we could be treated to a sky with two comets visible, as well as a fall meteor shower. That would be pretty amazing.

You can see the explainer video EarthSky did on the comet on the YouTube link above.