Sunset on Monday, 14 October 2024, was at 1750 MST. I went outside shortly after sunset to start monitoring the western sky for Comet Tsuchinshan-ATLAS (C/2023 A3).

1824 MST: The comet was visible in 7x50 binoculars.

1835 MST: Comet tail visible naked eye.

1847 MST: Comet tail at least 10° long to the eye.

1918 MST: Comet tail 15° long to the eye. The bright moonlit sky really hampered the view though.

1936 MST: Comet was now more difficult to see due to the moonlit sky and the haze along the western horizon now that the comet was much lower in the sky.

Here are iPhone 15 Pro Max and D850 DSLR photographs in chronological order. The comet's anti-tail appears in some of the photos.

1836 MST: iPhone 15 Pro Max Night Mode, (3 seconds, 2X lens)


1844 MST: D850 DSLR (f/1.8, 1 second, ISO 800, FL 50mm)


1849 MST: iPhone 15 Pro Max (Night Mode, 3 seconds, 2X lens)


1903 MST: iPhone 15 Pro Max (Night Mode, 10 seconds, 1X lens)


1906 MST: iPhone 15 Pro Max (Night Mode, 10 seconds, 5X lens)


1907 MST: iPhone 15 Pro Max (Night Mode, 10 seconds, 2X lens)


1930 MST: D850 DSLR (f/1.8, 5 seconds, ISO 800, FL 50mm)


1932 MST: iPhone 15 Pro Max (Night Mode, 10 seconds, 2X lens)

1900/1915/1930/1945 MST: D850 DSLR (f/1.8, 1 second, ISO 800, FL 50mm)

Click or tap on image for larger version

I got up after midnight on Tuesday, 15 October, to watch the SpaceX Falcon 9 rocket launch from Vandenberg Space Force Base in California. These iPhone 15 Pro Max photos (Night Mode, 3 seconds, 2X lens, cropped) show the launch. The 2nd stage engine burn appears in all five photos. The 1st stage re-entry burn (red dot just above the horizon) appears in the last three photos. The waxing gibbous Moon made a very bright moonlit sky.

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