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View submission: Ask Anything Wednesday - Physics, Astronomy, Earth and Planetary Science
"Falling" might not be the best term to use for building intuition. It's technically accurate (if we interpret "falling" to mean under constant unopposed gravitational acceleration), but may lead to some incorrect interpretations of what's really happening.
Everything in space is being accelerated by the gravity associated with other massive objects. In practice, this generally means something very large (e.g., a star or a black hole) has other things orbiting around it (e.g., planets or stars). Let's use Earth orbit as a useful example; Something like the ISS is "falling" because it's constantly being pulled towards the Earth with nothing opposing it. The reason the ISS stays in orbit is because it's moving so fast sideways that the Earth curves out under it to match the curvature of the ISS trajectory. Different orbits are all being accelerated by Earth's gravity, but had different initial states that let them travel in different ways.
The "different directions" thing is also addressed by the existence of other gravitating bodies. Something near the Moon, for example, is still being accelerated by the Earth but is being accelerated more so by the Moon, enough so that it travels in a captured Lunar orbit. Gravity scales linearly with mass, but scales inversely with the relative distance squared. This means that bigger objects exert more gravity, but closer objects exert **much** more gravity. This is why things can orbit the Earth, as opposed to exclusively being affected by the Sun or the black hole in the center of the Milky Way.
There's nothing here!