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Twin Green Comets Brighten For Best Views Under Next Week’s New Moon

The upcoming new moon aligned with the Orionid peak provides dark skies that favor binocular views of both green comets.

A bright Orionid is captured on the peak night of the shower by a NASA all sky meteor camera in western North Carolina.
Here’s the location of Comet C/2025 A6 (Lemmon) on the morning of October 17, 2025. This view shows the northeastern sky 90 minutes before sunrise for longitude 90° west and latitude 40 north°. At this time and for this location, the comet will be 16° above the horizon. Credit: M. Zastrow/Stellarium
Comet C/2025 A6 (Lemmon) appears in the sky above Molfetta, Italy, on October 11, 2025, around 6:00 AM to the right of the Big Dipper, before dawn. Comet C/2025 A6 (Lemmon), discovered at the beginning of the year, experiences an unexpected and sudden increase in brightness during the summer, quickly becoming one of the most interesting celestial objects of 2025. It is dubbed the most beautiful comet of autumn. (Photo by Davide Pischettola/NurPhoto via Getty Images)
A meteor shower in the Kubuqi desert, Inner Mongolia, China, in 2020. (Image credit: bjdlzx via Getty Images)

Overview

  • Comet Lemmon (C/2025 A6) and Comet SWAN (C/2025 R2) are now visible from the Northern Hemisphere, with a reliable 30‑minute window starting about 90 minutes after sunset.
  • Lemmon sits near the Big Dipper in the northwest and can also be seen before dawn, while SWAN is low in the southwest after sunset against rich Milky Way starfields.
  • Peak viewing is forecast for Oct. 20–21 during the new moon and Orionid meteor shower, offering the best chance to spot the comets with binoculars from dark sites.
  • Reports agree Lemmon’s closest approach is Oct. 21, though published distances conflict, with some sources citing about 28.6 million miles and others about 55–59 million miles.
  • Lemmon was discovered Jan. 3 by the Mount Lemmon Survey, follows an ~1,350‑year orbit with perihelion on Nov. 8, and models indicate a slight orbital shortening after this passage.