How do I open a calendar door?

Simply click on the door corresponding to the current day. Future doors remain locked to keep the surprise intact.

Is it free to view and open this advent calendar?

Yes, accessing and opening the doors on public calendars is 100% free for everyone.

Yes, each theme has custom background music and sound effects that trigger when you interact with the doors.

Embark on an astronomical journey. 12 nights exploring constellations, lunar craters, meteor showers, nebulae, and our solar neighbors.

FromNov 30, 2025

ToDec 12, 2025