WO RedCat51 refractor, ZWO ASI183MC camera with Optolong L-Pro filter, SkyWatcher EQ6R Pro mount.
Five 4-minute lights plus calibration frames were stacked using DeepSkyStacker; other post-processing was with Siril, Photoshop CS2 plus Astronomy Tools plugin, and PhotoScape X.
Last night I captured this image of comet C/2017 K2 (PANSTARRS) during the short period of time between darkness and the comet passing behind trees in my backyard. This large comet (located in the constellation Ophiuchus) is currently 280,120,714 km from Earth. It took over 15 minutes for the photons from the comet to reach my camera! The sphere of gas (coma) surrounding C/2017 K2 has an estimated diameter of 130,000 km, which is 10 times the Earth's diameter! The comet's closest approach to Earth will be on 14 July 2022.