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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 to

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.

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.