Look
Two comets, C/2025 A4 (Lemmon) and C/2025 R2 (SWAN), are about to make their closest approach to Earth and you can watch the action unfold live online.
Astronomer Gianluca Masi and his Virtual Telescope Project will host a special live broadcast on October 20 starting at 1:30 pm EDT (1730 GMT) to watch as both comets pass close to Earth, putting them in a good location for observations.
“Until now, living in the northern hemisphere, I have only been able to admire C/2025 A6 Lemmon,
but C/2025 R2 SWAN quickly joins the show and we are ready to surprise everyone.
astronomy lover with our live broadcast!” Masi told Space.com in an email.
You can watch the cosmic spectacle live here on Space.com, courtesy of the Virtual Telescope Project or on the project website either youtube channelif time permits.
Rare encounter with a double comet
Having two comets visible in the sky at around the same time is a rare cosmic treat. During the event, Comet Lemmon (C/2025 A6) will pass within about 90 million kilometers (56 million miles) of Earth, while Comet Swan (C/2025 R2) will come even closer, at approximately 39 million kilometers (24 million miles). Both are expected to reach their maximum brightness between October 20 and 21.
Comet C/2025 A6 (Lemmon) was discovered in January 2025 and has been brightening steadily as it rises through the interior. solar system. Lemmon is visible with a pair of binoculars or small telescopes in the western evening sky after sunset, slowly rising each night as it moves north.
Comet C/2025 R2 (SWAN) was discovered in September 2025 by the Solar and Heliospheric ObservatoryThe SWAN instrument is best seen in the predawn sky, when the comet appears low on the eastern horizon as it continues its journey away from the sun.
If you’re hoping to spot the comets yourself, check out our guides to best binoculars and The best telescopes for beginners.as well as ours guide on how to photograph kites. And don’t forget to explore us. night sky guide to more celestial highlights this month.
Editor’s Note: If you capture a photo of Comet Lemmon or Comet SWAN and would like to share it with Space.com, please send your images and comments to spacephotos@space.com.
