We haven’t seen Federation starships crashland on planets very often in Trek, and so when Discovery plows into this icy planet, it’s easy to be reminded of two of the most famous starship crashes in Trek history. In Star Trek: Generations, the Enterprise-D’s saucer section crash-landed on the planet Veridian III. In Star Trek Beyond, the saucer of the reboot Enterprise suffered the same fate. Lower Decks recently referenced starship crashes in Episode 9, when the Cerritos crash landed on a planet, too. But, in all these cases, the ships that crashed did not fly away intact after the crash. As Saru mentions later, he’s “aware that starships were not designed to lift-off in this fashion.” The only Trek ship that consistently did take off and land on planets (other than shuttles and smaller ships) was the USS Voyager. But, in the episode “Timeless,” even Voyager had a crash on an ice planet.
Discovery uses “graviton beams” to cushion the crash landing. This tech has been mentioned throughout Trek, but most notably in the Voyager episode “Scorpion Part 2.”
Nhan in the credits!
Actor Rachael Ancheril is listed in the opening credits seemingly for the first time. Ancheril plays Nhan, the former USS Enterprise security chief who stayed with the crew of the Discovery after the end of Season 2. Later in the episode, Georgiou questions why Nhan stayed with Discovery and she mentions the death of Airiam. In the Season 2 episode “Project Daedalus” the human cyborg Airiam nearly killed Burnham and Nhan after she was hacked by Control. But, Airiam fought against this programming, sacrificed herself and saved Nhan and Burham.
Tilly foreshadows the twist ending
After Discovery crashes, Tilly mentions that because of all the technical failures on the ship, “we don’t know when we are.” This is the opposite of the premiere episode of Discovery Season 3, in which Burnham’s computer told her she was in the year 3188 right away. The information gap is relevant, too, since at the end of the episode we learn a year has passed for Burnham, while it’s only been like a day for the crew.
I don’t recall Terralysium being particularly icy
Reno mentions that the planet they are on is not their destination planet of Terralysium, because the terrain doesn’t match up. We only saw Terralysium in the Discovery Season 2 episode “New Eden.” In that episode Terralysium also had rings around it, which doesn’t appear to be the case here. Notably, Tig Notaro’s Reno doesn’t appear in “New Eden,” though she had joined the crew in the previous episode, “Brother.”