Is There Gravity in Space?
A fast YouTube search reveals a plethora of floating astronaut movies. They can spin in the air, juggle bubbles of water, and their hair seems ridiculous. It actually seems that there’s no gravity in house—however appearances are deceiving.
Astronauts in orbit are extra precisely in free fall. They’re always falling in the direction of Earth—which suggests Earth is conserving fairly the gravitational maintain on them. They simply occur to be additionally transferring quick sufficient that they hold lacking the bottom.
Gravity does weaken with distance. But for large objects like stars and planets, their gravitational attain is gigantic. Without Earth’s gravity, the Moon (which orbits roughly a thousand instances farther away than the International Space Station) would fly off into the depths of house. Instead, Earth retains it on a gravitational tether. Likewise, the Sun retains a grasp over not simply Earth and Jupiter and Pluto, however even the Oort Cloud of comets, which extends a full light-year away.
The Sun is topic to the gravity of the large black gap on the middle of the Milky Way. And the Milky Way itself dances to the gravitational drumbeat of different close by galaxies.
In quick, it’s onerous to seek out objects in house that aren’t topic to one thing else’s gravitational tug.