Thetis, minor planet designation 17 Thetis, is a stony asteroid from the inner regions of the asteroid belt, approximately 90 kilometers in diameter. It was discovered on 17 April 1852, by German astronomer Robert Luther at Bilk Observatory in Düsseldorf, Germany who deferred to Friedrich Wilhelm August Argelander the naming his first asteroid discovery after Thetis from Greek mythology. (Wikipedia)
The video and image show the movement of Thetis over a 90-minute period on December 13, 2021.
Tech Specs: Orion 8" f/8 Ritchey-Chretien Astrograph Telescope, Celestron CGEM-DX pier mounted, ZWO ASI290MC and ASI071MC-Pro, ZWO AAPlus, ZWO EAF, 90 x 60 seconds at -10C plus darks and flats, processed using PixInsight and DSS. Image Date: December 13, 2021. Location: The Dark Side Observatory, Weatherly, PA, USA (Bortle Class 4).