At the beginning of the episode Jack O'Neill says, "I've seen this movie, it [the asteroid] hits Paris." This is a reference to the movie Armageddon (1998) starring Bruce Willis.
The asteroid is 137 km across. The one that killed the dinosaurs around 65 million years ago, Chicxulub, was only between 11-81 km across, making this asteroid substantially larger and orders of magnitude more destructive.
When boarding the downed Al'kesh, Carter assigns priorities of repair. One crewmen asked for "the bathroom" as that's his "priority". Likely a nod to sci-fi (very) rarely featuring places for people to pee on a ship or station. Babylon 5 (1993) bucked this trend, as did Star Trek: Enterprise (2001), sort of.