1Two surprising facts first
Gravity is still there — and "heavy" means something pushes back
You only need two ideas. Watch each one:
Gravity doesn't stop in space
Earth's pull reaches way up. Where the space station flies, gravity is still almost as strong as on the ground — about 9 out of every 10 pulls you feel right now.
"Heavy" is the floor pushing you
You feel your weight because the floor shoves back up on you. That support force is different from the downward pull of gravity. A floor can push only while it presses against you.
2Two ways to be up high
The bolted tower vs the falling ship
Picture two stations at the exact same height, in the exact same strong gravity. They behave in opposite ways:
Bolted to a giant tower
The tower holds the station at a fixed height. Gravity still pulls down on everything there.
Let go into orbit
Nothing holds it. The whole ship falls — but races sideways so fast it keeps missing the ground.
3Your turn — be the rocket
How fast sideways do you need to go to keep missing Earth?
Gravity always curves the ship's path down toward Earth. Slide the sideways speed and watch where the ship goes. Too slow and it crashes. With the right sideways speed, its curved path keeps missing Earth. This model leaves out air drag.
4Now run the real test
Same height and gravity. Which floor keeps pushing?
Two stations sit at the same height in the same strong gravity. One is bolted to a tower (held still). One is let go into orbit (falling). Predict first — then let the astronaut go and watch.
Guess before you let them go
Two cabins have the same gravity. One is held by a tower and one orbits freely. Which astronaut keeps feeling a floor push?