Overview
- ATLAS (C/2025 K1) hits perihelion on October 8 and could fragment during its solar passage, with best views near dawn and stronger visibility from southern latitudes, according to MDR.
- SWAN (C/2025 R2) is forecast to make its closest pass around October 20 with an uncertainty of about five days, at roughly 30–39 million kilometers depending on the source.
- Predictions put SWAN near magnitude 7.3 with potential to brighten to about 6.5, and MDR reports a striking tail around 4.5 degrees, making it primarily a binocular target.
- Lemmon (C/2025 A6) is expected nearest on October 21 at about 90 million kilometers with brightness near magnitude 8, with some experts suggesting possible naked-eye visibility under favorable conditions.
- The comets were discovered in 2025 by different teams and tools—Mount Lemmon Survey (Lemmon), ATLAS (ATLAS), and an amateur using SOHO/SWAN images (SWAN)—and none pose an impact threat, ESA notes.