Overview
- Skywatchers in the Northern Hemisphere have a brief viewing window about 90 minutes after sunset, lasting roughly 30 minutes.
- Comet Lemmon (C/2025 A6) is the brighter target low in the northwest near Arcturus in Boötes, while Comet SWAN (C/2025 R2) sits in the southwest beneath the Summer Triangle.
- Both comets are receding from Earth, and a brightening moon over the coming nights will rapidly make them harder to see, making Friday the best remaining opportunity.
- Use binoculars (8x42 or 10x50 recommended) and dark-sky locations; expect diffuse, fuzzy patches with tails, and consider apps like Stellarium, SkySafari, or finder charts from In-The-Sky.com.
- Lemmon last visited the inner solar system in 875 and is due again around 3175, while SWAN’s orbit is about 20,000 years, with Lemmon heading for perihelion on November 8.