Two comets, C/2025 A4 (Lemmon) and C/2025 R2 (SWAN), are about to reach their closest approach to Earth and you can watch the action unfold live online.
“So far, living in the Northern hemisphere, I could admire C/2025 A6 Lemmon only, but C/2025 R2 SWAN is quickly joining the show and we are ready to amaze every astronomy lover with our live feed!”
During the event, Comet Lemmon (C/2025 A6) will pass about 56 million miles (90 million kilometers) from Earth, while Comet Swan (C/2025 R2) will soar even closer, at roughly 24 million miles (39 million km).
Comet C/2025 R2 (SWAN) was discovered in September 2025 by the Solar and Heliospheric Observatory’s SWAN instrument.
Editor’s note: If you capture a photo of Comet Lemmon or Comet SWAN and would like to share it with Space.com, send your images and comments to spacephotos@space.com.
You can watch the action live online as two comets, C/2025 A4 (Lemmon) and C/2025 R2 (SWAN), approach Earth closes.
On October, the Virtual Telescope Project, led by astronomer Gianluca Masi, will broadcast a special livestream. Twenty starting at 1:30 p.m. m. EDT (1730 GMT) to observe both comets as they approach Earth closely, which puts them in a good position for observations.
“As a Northern Hemisphere resident, I have only been able to admire C/2025 A6 Lemmon thus far.
However, C/2025 R2 SWAN is coming soon, and we’re prepared to wow everyone.
With our live feed, astronomy enthusiasts!” Masi wrote in an email to Space . com.
According to the Virtual Telescope Project, you can watch the cosmic show live here on Space . com or, if the weather permits, on the project’s website or YouTube channel.
An uncommon double-comet encounter.
It is a rare cosmic treat to see two right comets in the sky at roughly the same time. During the event, Comet Swan (C/2025 R2) will fly even closer to Earth, at about 24 million miles (39 million km), while Comet Lemmon (C/2025 A6) will pass about 56 million miles (90 million km). The brightness of both is predicted to peak in October. October 20th and Oct. 20.
Since its discovery in January 2025, Comet C/2025 A6 (Lemmon) has been gradually becoming brighter as it flies through the inner solar system. Lemmon can be seen in the western evening sky after sunset through a pair of binoculars or a small telescope. As it moves north, it gradually gets higher each night.
The Solar and Heliospheric Observatory’s SWAN instrument made the discovery of Comet C/2025 R2 (SWAN) in September 2025. When the comet is low on the eastern horizon, continuing its journey away from the sun, it is best viewed in the predawn sky.
See our guides on the best binoculars and beginner-friendly telescopes, as well as our guide on taking comet photos, if you want to see the comets for yourself. For more celestial highlights this month, don’t forget to check out our night sky guide.
Note from the editor: If you want to share a photo you took of Comet Lemmon or Comet SWAN with Space . com, send it to spacephotos@space . com along with your comments.
