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Atmosphere
Interior and surface, by mass
Atmosphere
Inside, from the centre out
Drag to orbit · Pinch to zoom · Two fingers to pan
Tap an object for details · Double-tap to follow it
Pick an object, then tap the view. Orbit drops it into a circular orbit around whatever pulls hardest there; Place drops it at rest relative to that body. Drag instead of tapping to fling it.
Newtonian N-body gravity in units of AU, solar masses and years. Sizes are true to scale, so small worlds show as dots until you zoom in. Bodies merge on contact and break apart inside the Roche limit. Climate, atmospheres and stellar ageing run alongside.
Checking graphics support…
Double-tap an object to lock the camera on it. Surface lock turns the camera with a locked planet, so the ground below stays still.