How fast do rocket ships go?

In order to overcome the pull of the Earth's gravity, rockets need to achieve high velocity. While reaching low-Earth orbit requires speeds of at least 17,000 mph, the fastest spacecraft ever built managed to reach speeds of 157,000 mph.

Rockets need to produce tremendous thrust in order to overcome both gravity and the resistance of the Earth's atmosphere. According to Northwestern University, the amount of thrust needed to lift huge amounts of fuel into space can greatly limit the velocity of a rocket during launch. Once in space, satellites and other spacecraft require less thrust to accelerate and are able to achieve far greater speeds.