Every drop uses the same physics: distance fallen is half g times t squared, impact velocity is g times t. The gravity figures are rotation-corrected, meaning they reflect the pull you’d actually feel on a planet’s real, spinning surface rather than the tidier textbook number worked out from mass and radius alone. Earth, Mars, Mercury, Venus and Pluto spin too slowly for this to matter. Jupiter, Saturn and Neptune don’t, so their figures are adjusted.

WASP-17b breaks the pattern. It’s an exoplanet, so its gravity comes straight from mass and radius rather than a rotation correction. Studies since its discovery have settled around 0.48 Jupiter masses, though NASA’s exoplanet catalogue still lists 0.78, taken from one high-uncertainty measurement. We’ve gone with the consensus figure, since that’s what earned WASP-17b its reputation as one of the least dense planets ever found.

Radius and distance from the sun only decide the sort order, not the gravity. The ball stays the same size on every planet, so its look never hints at mass or gravity.

The bounce on landing is stylised, not physics: the height never changes. What does change, in line with each planet’s real gravity and impact speed, is how long the bounce lasts and how much the ball flattens on impact.