To lift the 4.5 million pound shuttle from the pad to orbit (115 to 400 miles) above the Earth, the shuttle uses two solid rocket boosters, three main engines of the orbiter, the external fuel tank...
A very low level, called microgravity, that's a small fraction of normal gravity. Astronauts feel weightless, by comparison.
Space shuttles orbit at a distance of 100-200 miles above the Earth. The...