Solar Sandbox

Solar Sandbox is a hands-on universe you build with your fingertips, and a space guide that teaches how it all works. Tap to place a star, then drag and release to fling planets into orbit. Orbit Guide works out the speed for a clean circular orbit, and a dotted path shows where a world will travel before you let go. LIVING WORLDS Planets react to their star. Rocky worlds in the green habitable zone grow oceans, continents and clouds. Too close and they melt into lava; too far and they freeze over. Sling an icy comet into a dry world to bring the water back. COSMIC EVENTS • Make a star go supernova and leave a spinning black hole behind • Watch moons that stray too close to a gas giant break into rings • Crash worlds together and watch them merge in a burst of fire SPACE GUIDE Thirty illustrated topics for curious minds of all ages: the Sun, the Moon and every planet, comets and asteroids, stars, black holes, galaxies, gravity, light-years and more. Each topic has easy-to-read sections, key numbers, "Did you know?" facts, words to know and a quiz. A glossary and a mixed quiz help you study, and your progress is saved as you go. 15 CHALLENGES TO EARN Grow a living world, give a gas giant rings, feed a black hole, build a family of planets and more. Earn a badge for each one. CALM SPACE MUSIC Original ambient music and sound effects, with switches to turn either off. FOUR READY-MADE SYSTEMS • Our Solar System • Binary Stars: twin suns with a world circling both • Black Hole Trap: comets and rocks swirling around a black hole • Proto-Planetary Chaos: young rocks colliding into planets CONTROL TIME AND SPACE Pause, slow to half speed or speed up to 50×. Pinch to zoom and follow any planet as it travels. PRIVATE BY DESIGN Your universe is saved on your device only. No account, no ads, no tracking. Solar Sandbox is a simplified, playful simulation, not an astronomy reference.