Two Rare Comets Are in the Skies Above Earth. How to See Them
Two unique comets are currently crossing our skies, and it’s a rare treat because they won’t return for hundreds of years. Comets C/2025 A6 (Lemmon) and C/2025 R2 (SWAN)look alike.
You can spot these green gaseous orbs and their tails streaming now, with SWAN shining brightest on Monday, October 20, NBC News reports. Just one day later, on Tuesday, October 21, Lemmon will reach its peak in the dark sky.
You’ll be able to see Lemmon without any equipment, but SWAN will be quite faint, says Jason Steffen, assistant professor of physics and astronomy at UNLV.
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“Current models show the [Lemmon] “The comet will likely reach a magnitude between 3.5 and 4.5 when it is closest to Earth on October 21, which is fainter than it showed last week,” the Saint Louis Science Center wrote in an update. “It is still bright enough that it can become visible to the naked eye from light-polluted locations.”
CNN reports that SWAN will return in 650 to 700 years, and Lemmon won’t return for 1,300 years.
“Comet Lemmon is called a non-periodic comet. Unlike Halley’s Comet, which comes every 76 years, the orbit of a non-periodic comet is really very elliptical,” says Steffen. “The last time it was here was in the 700s.”
Comets are known to thwart even the most conservative predictions, but careful observers might spot these rare spectacles in October from their backyard, in the morning or night sky before dawn.
New comets enter the scene
Both Lemmon and SWAN were discovered in 2025. Lemmon was discovered on January 3 in Arizona by the Mount Lemmon Survey using a 60-inch telescope installed on Mt. Lemmon to find celestial objects, which gave the comet its name.
A Ukrainian amateur astronomer named Vladimir Bezugly discovered comet SWAN on September 11 while examining images captured by SWAN, a scientific instrument called Solar Wind ANisotropies, installed on the Solar and Heliospheric Observatory in Space.
“It was an easy comet to detect because of its sufficient brightness in the (ultraviolet) band and its location in the SWAN images, exactly at its center,” Bezugly told Universe Today. He also noted that this is the 20th official SWAN comet to date.
How to see Lemmon and SWAN this month
The darker the night sky, the easier it will be to see comets, moons, planets and stars. If you live in the city, bundle up and head out in the evening to observe the sky in the countryside, where there is less light pollution. Oh, and grab some blankets, chairs, and something warm to drink.
It takes time for your eyes to adjust to the dark. Find a comfortable place where you can stay still and look up. Comets may be bright enough to see unaided, but NASA recommends binoculars as a great beginner stargazing tool.
Telescopes are one of the best ways to observe the sky, and you may be able to find one to use or rent at your local library or university. But modern telescopes can also be quite affordable.
Smartphone The apps can also be useful in trying to identify celestial phenomena and where to find them. For some recommendations, check out our list of stargazing apps.
A sky full of wonders
Besides the recently discovered comets, skywatchers will have a few other cosmic treats to enjoy this month.
THE Orionid meteor showerwhen Earth passes through the massive tail of Halley’s Comet, began earlier this month, but you’ll be able to see the meteors until early November.
The next super moonknown as the Beaver Moon, will take place on November 5.
