Ah damn. Got a headache and now I am confused. Please clear up. So if you move a spacecraft up from low earth orbit, its orbital velocity decreases by the formula. But if you reduce the velocity, say due to atmospheric drag or by lowering the velocity by itself, why does the space craft reduce in altitude?
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Ah damn. (1 Viewer)
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mysterymarkplz
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Use your orbital velocity formula, V = root(GM/r), as R decreases, the V required to stay in orbit increases. So if you have insufficient V to maintain that orbit, it'll just plummet down towards Earth, and since atmospheric drag reduces V, it can't stay in that orbit hence it'll decrease to the next orbit, and since the next orbit requires a higher V, it'll just keep descending. Keep in mind that the equation doesn't mean, "if you increase R, then V decreases and if you decrease R, V increases", while it looks like that mathematically, the formula is just to state what V must be to maintain at a certain R.