1830 MST: Began my Comet C/2025 A6 (Lemmon) observing session Monday evening, 20 October 2025. The comet was near its closest to the Earth (about 55,417,560 miles).

1831 MST: Comet visible in 7x50 binoculars. Coma, but no tail.

1836 MST: Comet tail faintly visible in 7x50 binoculars.

1848 MST: Comet faintly visible to naked eye.

1859 MST: Comet tail about 2° long in 7x50 binoculars.

1900 MST: Comet a little easier to see with naked eye.

1915 MST: Ended observing.

I took the following photographs using a tripod mounted D850 DSLR with 70-300mm lens and a handheld iPhone 15 Pro Max. Planes and satellites are very obvious in the photos, as is skyglow from the community of Casa Grande.

1852 MST: D850 DSLR (f/4.5, 6 seconds, ISO 5000, FL 70mm)

Click or tap on image for larger version

1856 MST: D850 DSLR (f/5.6, 1 seconds, ISO 25600, FL 300mm)


1906 MST: iPhone 15 Pro Max (Night Mode, 10 seconds, 2X lens)


1913 MST: D850 DSLR (f/4.5, 6 seconds, ISO 6400, FL 70mm)

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