Aliens. Alien intelligence. Alien vessel shapes and what it says about the show you are about to watch. Moebius ships?
When your crew is this good, you really should just send a ship without the humans on it instead. MapQuest in spaaaaaace being confounded by gravitational lensing. Dark matter… blocks your view sometimes? Rogue planets and how very very very dark it is in between star systems. Robinson Crusoe oxygen rocks (or crystals).