C/2025 A6 (Lemmon) taken by Daniel Opdyke

Telescope:   Atrotech AT 72ED II 72mm aperture 430mm focal length f/6
Mount:         Iopteron CEM 25 hypertuned
Exposures:   60 subframes @ 60 sec each over 1 nights for 1 hour of integration; ASI533MC-P; UV/IR filter
Processing software: Siril
Location, Bortle, and Date: Washington Crossing Park soccer fields; Bortle 6; October, 2025
Description and Story: Comet C/2025 A6 (Lemmon) is a long-period, non-periodic comet discovered on January 3, 2025 by the Mount Lemmon Survey in Arizona. It follows a highly eccentric, retrograde orbit, meaning it moves opposite the direction of the planets, and it likely originated in the distant Oort Cloud. The comet reached perihelion on November 8, 2025 at about 0.53 AU from the Sun and made its closest approach to Earth in late October 2025 at roughly 0.60 AU. Although it was extremely faint at discovery, it brightened far more than early predictions, reaching around magnitude 3.5–4 at peak, making it visible to the naked eye under dark skies and a strong binocular target. As it approached the Sun, heating drove strong outgassing that produced a prominent coma and both dust and ion tails, with spectroscopic observations revealing typical cometary gases such as carbon-based species and sodium. Scientifically, Lemmon is valuable because comets like it preserve primitive material from the early solar system, offering insight into its original composition and the processes that shaped planetary formation.