A pocket astronomy course — planets, stars, galaxies & beyond.
About
Cosmos is a Duolingo-style journey through the universe. Travel a path of bite-sized lessons across five units — The Solar System, Stars & The Sun, Earth & The Moon, Galaxies & Beyond, and Space Exploration. Answer quick quizzes, identify planets and stars, match concepts, and learn the real science behind day & night, the phases of the Moon, black holes and the Big Bang. Earn XP, build a daily streak, and rank up from Stargazer to Astronaut. Progress saves automatically — no ads, no account needed.