The object 2022WJ1 was a small (0.5-1 metres in diameter) Apollo near-Earth asteroid.
It was discovered two hours before the impact by the Mt. Lemmon Observatory (G96) of the Catalina Sky Survey.
Although this kind of impact events occur quite frequently, this case was the sixth after 2008TC3, 2014AA, 2018LA, 2019MO and 2022EB5 which were discovered before impact.
The Impact occurred on 19 November 2022 at 08:27 UTC, near Grimsby, Ontario, Canada.