Why astronauts float: the space station never stops falling

Astronauts on the International Space Station look weightless, but at 400 km up, Earth's gravity is still about 90% as strong as on the ground.

The trick is that the station is falling, all the time. It moves sideways at roughly 28,000 km/h, so fast that the Earth curves away beneath it as quickly as it drops. It keeps missing the ground. Fire Newton's famous cannon yourself and find the speed where a falling ball turns into an orbit.