How far is it to space??

Question

I need to know how mant feet to the ionisphere/Miles is ok also

Answer 1

100 KILO?

Answer 2

Officially, the boundary is considered to be 100 kilometres straight up. That's an hour drive...

But it's hard to really draw a definite practical line. Air particle density drops as you get farther from Earth, with no clear defined altitude where it ends.

If you want the outermost ionosphere, then perhaps a few thousands of kilometres up.

Answer 3

It all depends.

The altitude of the point where the space shuttle reaches "atmospheric interface", for instance is 75 miles (400,000 feet).

However, the Aeronautique federation of France recognizes the boundary of space as 100 kilometers (62 1/2 miles).

And, finally, the boundary where a satellite can maintain an orbit around the Earth is believed to be around 250 kilometers (150 miles), or about 800,000 feet.

BTW, the International Space Station orbits at about 1.2 million feet in altitude (or about 225 miles up).

Answer 4

If we say that the thickness of the earth's atmosphere is 20m, we are making a definition based on enclosing 99 percent of its mass. But this is an arbitrary choice. If we define the thickness as enclosing 99.9 percent of the mass, the answer is 25m. If you demand that the particle count per cubic meter be indistinguishable from the density of the solar wind in the vicinity of the earth's orbit, you have to go to something like 1000m.

The ionosphere is between 45m and 1000m.

Answer 5

the higher you go, the thinner the atmosphere gets.

someone artificially defined it as 50 miles, or 100 km.

if you remember, that's how high spaceship-1 went.

however, at that height, it had 0 velocity, not the 17,000 mph it would need to stay in orbit.

for myself, i think around 120-130 miles would be more appropriate.

when a satellite dips below 120 miles, it encounters sufficient additional air resistance that it slows, and fairly quickly falls out of orbit.

above about 130 miles, that process (slowing) is considerably reduced.