Why do our rockets, satellites, landers, and capsules all need propulsion systems, of some kind, while comets, meteors, asteroids, planets, moons, stars, appear not to need any kind of propulsion system whatsoever?
What power, presence, or force is enabling the heavenly bodies' persistent, orbital, continuous, super-fast and predictable motions in the sky?
Why can't we access it, whatever it is?
