Eli5: How do satellites stay in orbit, and don’t gravity pull them to the surface?
In: Earth Science
Until I found a random interest in space and rocket science, I thought rockets just went straight up, stopped, and used the baby thrusters to move themselves around. I found that wasn’t the case, there’s two points I want to make here. And I’m no professional so if I get anything wrong anyone feel free to correct me.
1. What goes up must come down
If a rocket is launched straight up, unless it goes fast enough to break itself away from the gravity of the earth [escape velocity] it will come straight down.
2. That obviously led me to discover that the only way a rocket can get in to earths orbit is by going up and at some point before leaving the atmosphere, side ways (go right or suffer). When you kill the throttle and coast to the top of that arc (apogee) , you will eventually slow down and start falling back to earth. But if you coast to the top of the arc and throttle up, you start going faster forward than you are down towards earth which causes the endpoint of that arc to change and eventually your arc will have widened so much that the ending point meets the beginning point. Now you’re going forward fast enough that earth is still pulling you down but, instead of falling back into the atmosphere and getting M3RK3D by drag, you fall to the other end of the circular (there are very few space craft in perfectly circular orbits) path you’re on around the planet.
*ADVANCED MODE*
So the way space craft change their orbits is by either 1. moving forward (prograde) faster and making the side directly across from it go higher
Or
2. Apply thrust the backwards (retrograde) and you will slow your forward speed and make the side directly across from it go lower until the other side of the circle touches earth and becomes two points bringing your path back to an arc. If you apply enough thrust in one direction it kills the movement in the other direct which makes the arc get skinnier. If you kill all forward momentum you fall back down and bump your head.
Hope my autistic writing skills made sense, it’s been a long day 😩
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