Why do astronauts feel weightless while in orbit?

The reason we feel weight isn't because gravity is pulling us down; it's actually because we can feel our body being "squished". When we're on Earth, gravity is trying to pull us down through the floor, but the floor can't move down - we are pushing down on the floor and we feel the floor pushing back, known as a "reaction force".When you're in orbit, all parts of your body are accelerating equally and, more importantly, there's nothing pushing back on you. While on Earth you can't fall because the ground gets in your way, in space you are falling and so you feel no reaction force. Because there's nothing trying to squash your bones when you're just floating in space, you don't feel that your body is compressed and so you experience weightlessness.