Question

Explain how orbital motion develops.

Answer 1

woo hooo, this is a question !
two bodies, one moving relative to the other get close together. BUT they don't collide, because the moving body is following a path that doesn't actually HIT the other body. Instead, because of the geometry of the path, it enters into an orbit around the other body.
When the apollo 13 mission was rescued, part of the rescue was to put the craft in a "sling shot" orbit round the moon so that it "hitched a ride on the moon's gravity" and was able to reverse direction (ie back to the earth)) without consuming on board fuel.
The world watched this happen on tv.
Although not directly about orbits, a big problem for space craft re entering the earth's atmosphere is to get the angle right. if it's too steep, there'll be burn up. if it's too shallow there'll be bounce off.
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