What goes up must come down, but as any aerodynamics engineer will tell you: getting it up is the hard part. On Earth, where our atmosphere is rather dense compared to many planets, we’re able to send aloft objects that are massive enough to be anchored to the ground through gravity via engineering based on simple physical science principles. As MIT puts it: Heavier-than-air flight is made possible by a careful balance of four physical forces: lift, drag, weight, and thrust. For flight, an aircraft’s lift must balance its weight, and its thrust must exceed its drag. A plane uses…

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