Answer: Hello there!
When the astronauts are in orbit, they are too far from Earth to experience enough gravity, this is why they are "weightless"
Non the less, is not like "there is no gravity there", gravity is what keeps the space shuttle in orbit, the astronauts "appear" weightless, but they aren't, they still have mass, and still are being affected by gravitational forces, but now the gravitational force from the earth is depreciable, and contrasted a little bit by other gravitational forces.