What are the Giant Telescope room's secrets?

Confirmed, however, the sequence is R RT L RT RT A A R. The blinking lights also correspond to RT and LT prompts. Just follow the lights and you get a weird red cube with a piece missing from it.

There are two secrets in this room.

Constellations

Look out the telescope at night and two tetrominos constellations will show in the stars. Rotate the telescope to get a sequence of eight. Enter the sequence, looping it in case you started at the wrong point. If you want to cheat, hover for the code:

→ RT ← RT RT A A →

Red star

To "complete" the room, observe the blinking red star in the telescope:

Turn your telescope to look in the direction of the entrance door. A blinking red star will show in the upper-left corner of the telescope's view at night. Press your left/right triggers in time with the blinking to unlock a red "heart" cube piece. The truncated code is RT LT LT RT RT LT.