The Doodle shows a winking moon half in shadow, surrounded by bronze cards that showcase various phases of the moon. When users click the image, they are taken to a matching card game.

Image caption, The part of the Earth ... Like the Earth, half of the Moon faces towards the Sun, and half faces away from it. As the Moon orbits the Earth, we see it from different angles.

More than half of the Moon’s visible surface is illuminated – this is a gibbous moon. Image caption, When the Moon is on the opposite side of Earth to the Sun, the illuminated part of the Moon ...