Continuity mistake: Just before the diner scene, where the two aliens are discussing the galaxy, we see the outside of the Russian restaurant. The neon sign says "haroshaya" meaning "good" all the way across the window, in the next shot inside the restaurant, the "ha", which looks like the English letters "xo", is gone and the sign is centered.
Continuity mistake: When the cat in on the table in the diner, the word "ORION" on the cat's collar is in normal capitalized block lettering. But when the cat is on the table in the morgue, the word "ORION" is in calligraphy. Also, the colour of the cat's collar seems to change between these two points.