Educational Material: The Virtual Gemini Card Game

Upcoming practice sessions!

We are planning on organizing open practice sessions for anyone to learn the game and get better at it. Once we have enough people ready for it, we will organize a tournament with real prizes. Stay tuned! (You can add yourself to the email list and get timely updates.)

About the Gemini Card Game

Gemini is distributing a card game with unique designs and challenging gameplay. The Gemini Card Game (GCG) is a cooperative game for 2 to 4 players who work together to complete science programs over the course of two-week turns for a semester. Experience the complex decisions required to run a world-class observatory and the excitement of contributing to a team as you provide researchers with their precious data and contribute to expanding the knowledge of the Universe.

Game and Graphic Design: André-Nicolas Chené
Development: André-Nicolas Chené, Jerry Brower

Social media: #GeminiCardGame

Gemini Card Game online!

GCG can now be played on the site Tabletopia

This means that:

  • You can play even if you do not have your own deck
  • You can play with anyone, anywhere
  • You can enjoy the improved gameplay, with a new game board and automated set-up
  • You will play with rare cards in future updates
Gemini Card Game

Get the rule book written for the Tabletopia version.

Do not worry, we will continue to distribute physical card decks as soon as in-person meetings can be resumed.

How to play on Tabletopia

You need to have an account with Tabletopia to access the game. The game is free and you can create an account for free, if you do not already have one.

To create a free account:

  1. Click on Sign Up on the top right corner of your screen.
  2. In the pop-up window that appears, enter your email, create a password, and click "SIGN UP."
  3. A bigger pop-up window like this will appear:
    How to play on Tabletopia
    Select the Bronze status for a free account.
  4. You can now edit your account, and access the GCG.

The Bronze account is free, and allows you to play up to two games simultaneously. It is plenty enough to access GCG!

Once on the GCG page, simply click the big, framed "Play Online," and invite people to join or share your link to wait for more people to join. Once the seats are filled with enough people, Start the game! For more on this, visit Tabletopia Beginner's Guide.

It may take some practice for new people on Tabletopia to get used to the game components. You can learn more on Interacting with Game Components on Tabletopia.

Gemini Card Game played in person

Do you prefer to play with physical cards rather than online? No problem. Click here to find out how to play in person!

How does it compare to reality?

Of course, it is just a game. At best, it is a simplistic model of the decision-making in place when the Gemini staff is scheduling and observing programs. Also, if 12 rounds is a semester, it means that each round is 2 weeks, and one should expect much more telescope time to be used in real life.

However, Band 1 programs take absolute priority, as they were estimated by peers to be the best use of the telescope time. Band 2 programs are preferable when there are no possibility to observe Band 1 programs. And Band 3 programs are essentially fillers, so good science may be possible when the weather is bad, or when nothing else is available.

Also, deciding on which target to observe is not always straightforward. Observing a setting target instead of a higher priority one, with the hope to catch that other target later is sometimes the best strategy.

Discover a support astronomer experience that is not too far from what really happens in Hilo and La Serena, and share it with us!


We would like to thank Mark Rawlings, Graham Bell, Ryan Berthold, Eileen Gonzalez, Paige Godfrey, and the Gemini North Game Club for their precious help with setting up the rules.


International Gemini Observatory/NOIRLab/NSF/AURA/A.-N. Chené

About the Education Material

Release date:Feb. 23, 2021, 7:27 a.m.


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