The Planetarium is a hidden room accessed through the Observatory, and while it doesn’t look like much at first, it comes with a powerful bonus: ending your day here gives you +2 Stars. It’s one of the few ways to boost your star count just by planning where you sleep.
Read More: All Rooms in Blue Prince
How to Access the Planetarium
-
Go to the Observatory
-
Use both the upper and lower dials on the telescope to adjust its position
-
Align it so the telescope stretches across to the ledge above
-
This will unlock a hidden compartment, revealing the Planetarium
It’s not marked on the floorplan until you solve this puzzle so you’ll need to interact with the telescope to make it appear.
What the Planetarium Does
-
It grants +2 Stars if you end your day inside the room
-
Contains a clue:
“A new constellation appears when you reach 5.”
-
Reaching 50 Stars unlocks a new method for redrawing rooms, giving you more control over your floorplan
-
Stars are used for unlocking advanced Observatory perks, constellation effects, and hidden mechanics
The Planetarium is one of the only rooms that passively buffs your long-term progress without draining Gems or Steps.
Why It’s Worth Using
-
Stars are hard to get—this gives you a guaranteed way to farm them
-
Helps you reach the 50-star threshold, unlocking new drafting effects
-
Ending your day here is easy to plan around if you build it near your end-of-day path
-
Pairs well with planning builds or any strategy relying on redrawing or constellation upgrades
Final Blurb
The Planetarium is quiet, out of sight, and easy to miss but ending your day there makes the stars just a little closer. If you’re chasing deeper constellations or better rerolls, it’s worth the detour. Sleep under the dome, and the manor might just look different tomorrow.
