km/s

kilometer per second

Speedexact by definition

The kilometre per second is exactly 1,000 metres per second. It is the natural unit wherever speeds are astronomical or seismic: Earth's orbital speed is 29.8 km/s, escape velocity from its surface 11.2 km/s, P-waves travel through the crust at 5 to 8 km/s, and galaxy redshifts are reported as recession velocities in km/s.

1 km/s 1,000 m/s