• Two comets, C/2025 A6 (Lemmon) and C/2025 R2 (SWAN), will be at peak visibility this week.
• Comet Lemmon peaks Oct. 21 near the Big Dipper at magnitude 4.5; Comet SWAN peaks Oct. 20 near the Summer Triangle at magnitude 5.
• Best viewing is 1.5 hours after sunset with binoculars in dark skies.