Last appearance of Little Cheeser.
All the mice move in sync with each other when Little Cheeser first comes and looks at the moon thru the telescope as it was probably easier to animate their movements together as opposed to creating individual and different movements for each mouse.
Buck Rogers, a popular cinematic space hero of the era, is referenced here as the inspiration for the home built rocket ship Cheeser pilots.
The mouseonauts pass by the milky way, the big and little dipper constellations, and the polar (north) star on their adventure.