I received a text notification from the folks at Vaonis that Comet C2025/A6 Lemmon would be visible in the early morning sky. I looked up the RA/Dec coordinates for the comet using Stellarium and programed them into targets for my Stellina, Vespera Classic, Vespera II, and Vespera Pro telescopes. The RA/Dec coordinates for 04:00 were 10h02m45s +41°05’14” which would be about 23° above the horizon to the northeast (near the big dipper). At 04:00 the comet was either blocked or just above the tree line. By 04:30 the comet could be observed by the telescopes.

Vespera Classic

The images are composites of 32 10-second images which is just over a 5-minute exposure. This exposure is long enough to see the comet tail. Longer exposures show movement of the comet head relative to the stars. The estimated magnitude of the comet is 13.1 (not yet visible to the unaided eye). The green color of the comet is due to diatomic carbon in the coma absorbing ultraviolet light and re-emitting it as green fluorescence. Note in three of the images a faint satellite trail is visible.

Vespera II