Overview

• Comet Lemmon (C/2025 A6) makes its closest approach around Oct. 21 and could be visible to binoculars or possibly the naked eye, with brightness still uncertain.
• The comet was discovered in January 2025 by the Mount Lemmon Survey and last visited the inner solar system in the seventh century, with a projected return around the year 3421.
• The Orionid meteor shower, active Oct. 2–Nov. 7, is expected to peak overnight Oct. 21–22 at roughly 20 meteors per hour under a new moon for darker skies.
• The American Meteor Society flags 2025 as a Taurid ‘swarm year,’ with a fireball surge forecast around Nov. 3–4 and the Northern Taurids peaking Nov. 8–9.
• A second visitor, Comet C/2025 R2 (SWAN), is also approaching in October and may be observable through binoculars, while early-month highlights include the Oct. 6–7 Harvest Moon, the Draconids on Oct. 8, and a Moon–Pleiades pass on Oct. 9.