Check out a previous post on gravity here, and another post on planetary orbit here. Gravi

Check out a previous post on gravity here, and another post on planetary orbit here. Gravity and Astronauts in Orbit Newton’s Law of Gravity states that the gravitational force between any two objects in the universe is proportional to the mass of the objects and inversely proportional to the square of the distance (measured from their centers) between them. That means that if you double the size of either of the masses, the gravitational force will double. Then also if you halve the distance between the two objects and their masses stay the same, the gravitational force between them will quadruple. The converse of both these statements is also true. Despite gravity keeping everything around you steadily on the ground, it’s considered to be the weakest force in relation to the other four fundamental forces. After all, you can easily overcome the gravitational force of the whole entire Earth for a few seconds by simply jumping or throwing a ball up into the air. A common misconception is that there’s no gravity in outer space. Anything with mass has an infinitely large gravitational field - but because it gets progressively weaker with distance, its effects quickly become negligible. Then why do astronauts float around in the space shuttle? Why are they weightless? The only reason you can feel your weight on Earth is because the Earth is pushing back up at you. It’s the normal force from the Earth on your body. However within an orbiting spacecraft, you’re in free fall. There’s nothing to push back at you and make you feel your weight!  Fun fact: Astronauts experience a lot of nausea and headaches during their first few weeks in orbit. This is probably because not only are they in free fall, but the liquids inside them are probably flowing around too (eg. fluids to the brain, nasal cavities, stomach contents, etc…) Sources 1, 2 and 3. -- source link

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