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Are we talking about the speed record? It depends on a number of variables, most notably being body position and altitude. The higher the altitude, the thinner

Are we talking about the speed record? It depends on a number of variables, most notably being body position and altitude. The higher the altitude, the thinner the air. Whereas terminal velocity at 10,000' MSL (mean sea level) is 120mph, if you go up to 30,000', terminal is faster due to less air molecules to create drag. As for body position, if I'm flying my body belly-to-earth, in a stable arched body position, I'll fall a lot slower than I will flying head-down with my arms tucked to my sides. Apparently, Felix was attempting to increase his speed by flying close to head-down - he flared out in mid-attempt when his visor began to fog and decreased his visibility. (You probably saw the spinning on the video as he reached close to 730mph - to me, that appeared to be the result of him flaring out of his head-down dive to a belly-to-earth body position in the thin air, which doesn't provide a lot of control). Additionally, if he were to make this jump in a latex suit, he'd be moving a lot faster due to decreased drag. (However, he'd also be dead from exposure to cold.) So the "natural upper limit" is basically however fast he went, given the equipment, altitude, and body position. If we change the variables, we'd get a different maximum speed. Terminal velocity is terminal velocity, given all those factors.

ezequiel-garzon 14y ago
Thanks for such a thorough reply! I'm very curious about the highest possible (and feasible) altitude. I couldn't find out how high you can go and still fall towards the Earth. (At some point you would just orbit the Earth, right?) Edit: Thanks to both replies. Never mind, then!
- avar 14y ago
  No, you won't orbit just by going high enough. To orbit you need to going fast enough horizontally that as you fall you never hit the body you're orbiting. If you just keep going straight up you'll eventually fall back to Earth, or be on your own independent orbit around the Sun.
- duskwuff 14y ago
  To orbit, he'd need horizontal velocity. I'm pretty sure you could, in theory, fall to Earth from anywhere short of Sun-Earth L1 (about 1.5 million! km) if you had zero velocity relative to Earth, and if you made sure to miss the Moon on the way down.
- losvedir 14y ago
  > (At some point you would just orbit the Earth, right?) No way. I think you really misunderstand how weightlessness works in space, and I can assure you it's much more interesting than you think. :-p While gravity does decrease with distance, it doesn't decrease nearly as fast as you think. For instance, at the altitude of the International Space Station (280 miles, or roughly ten times the altitude of this jump), the force of gravity is still 90% as strong as on the surface of the Earth. In fact the only reason people are "weightless" up there is because they're constantly falling towards the surface of the earth. (Think of if you're in an elevator whose cable snaps, you'll appear to be "weightless" inside the elevator). Fortunately for the astronauts, the ISS is moving horizontally so fast, that the Earth is actually falling away from them (due to it being round) at the same rate that they're falling to the ground. This is the same with, say, the space shuttle. The reason people seem to float in there is because the thing is falling like a rock. It just happens to be moving forward 17,000 mph, so the earth falls away with it.
  - lloyddobbler 14y ago
    This is absolutely fascinating...something I hadn't considered. But makes perfect sense. Thanks!
- ars 14y ago
  The biggest issue is getting up there. A balloon will only go so high, after that you'd need powered flight. The maximum speed is the escape velocity of earth. That's the fastest you can fall to earth - assuming you started from infinitely far away. Which also answers your question: The is no maximum altitude. (Although if you get far enough away you'll have a hard time aiming due to the orbit of the earth around the sun.) However you can cheat and power yourself toward the earth, and then there is no maximum speed.

ezequiel-garzon 14y ago

Thanks for such a thorough reply! I'm very curious about the highest possible (and feasible) altitude. I couldn't find out how high you can go and still fall towards the Earth. (At some point you would just orbit the Earth, right?) Edit: Thanks to both replies. Never mind, then!

avar 14y ago
No, you won't orbit just by going high enough. To orbit you need to going fast enough horizontally that as you fall you never hit the body you're orbiting. If you just keep going straight up you'll eventually fall back to Earth, or be on your own independent orbit around the Sun.
duskwuff 14y ago
To orbit, he'd need horizontal velocity. I'm pretty sure you could, in theory, fall to Earth from anywhere short of Sun-Earth L1 (about 1.5 million! km) if you had zero velocity relative to Earth, and if you made sure to miss the Moon on the way down.
losvedir 14y ago
> (At some point you would just orbit the Earth, right?) No way. I think you really misunderstand how weightlessness works in space, and I can assure you it's much more interesting than you think. :-p While gravity does decrease with distance, it doesn't decrease nearly as fast as you think. For instance, at the altitude of the International Space Station (280 miles, or roughly ten times the altitude of this jump), the force of gravity is still 90% as strong as on the surface of the Earth. In fact the only reason people are "weightless" up there is because they're constantly falling towards the surface of the earth. (Think of if you're in an elevator whose cable snaps, you'll appear to be "weightless" inside the elevator). Fortunately for the astronauts, the ISS is moving horizontally so fast, that the Earth is actually falling away from them (due to it being round) at the same rate that they're falling to the ground. This is the same with, say, the space shuttle. The reason people seem to float in there is because the thing is falling like a rock. It just happens to be moving forward 17,000 mph, so the earth falls away with it.
- lloyddobbler 14y ago
  This is absolutely fascinating...something I hadn't considered. But makes perfect sense. Thanks!
ars 14y ago
The biggest issue is getting up there. A balloon will only go so high, after that you'd need powered flight. The maximum speed is the escape velocity of earth. That's the fastest you can fall to earth - assuming you started from infinitely far away. Which also answers your question: The is no maximum altitude. (Although if you get far enough away you'll have a hard time aiming due to the orbit of the earth around the sun.) However you can cheat and power yourself toward the earth, and then there is no maximum speed.