Comet expert Michael Mattiazzo captured this image of the new comet R2 SWAN this past week using a 200mm lens. Note the circle around a faint object at upper right. That’s the interstellar comet 3I/ATLAS! Used with permission.If you like Comet SWAN, you’ll love Comet Lemmon, which is forecast to become even brighter than SWAN! Read about Comet Lemmon here. And don’t forget about our interstellar comet, 3I/ATLAS. October 2025 is a great month for comets! | EarthSky
Larry Sessions has written many favorite posts in EarthSky's Tonight area. He's a former planetarium director in Little Rock, Fort Worth and Denver and an adjunct faculty member at Metropolitan State University of Denver. He's a longtime member of NASA's Solar System Ambassadors program. His articles have appeared in numerous publications including Space.com, Sky & Telescope, Astronomy and Rolling Stone. His small book on world star lore, Constellations, was published by Running Press.| earthsky.org