2007-10-03 09:39:35 · 7 answers · asked by drew_wyatt 1 in Science & Mathematics ➔ Astronomy & Space
wizjp and ausbeastie42 do not understand what escape velocity is.
Contrary to popular belief, it is certainly NOT necessary to travel at escape velocity in order to reach outer space. Not even the space shuttle reaches escape velocity.
In fact, the TierOne spacecraft (winner of the Ansari X-prize) reached outer space by traveling at the "modest" speed of 932 mph.
Escape velocity is the speed you need to reach if you wish to _coast_ continually farther away from the earth forever (with engines turned off). You CANNOT orbit the earth if you go at escape velocity, because you will simply move ever farther away from the earth rather than looping around it.
Orbital velocity (which is about 70% of escape velocity) will let you circle the earth with your engines off.
But suppose you don't turn your engines off? If you can _maintain_ your 76mph speed continuously (for example, using rocket engines that can burn for a long, long time), then it would take you about 47 minutes (using the "standard" distance of 60 miles to the top of the atmosphere).
The problem is, if you then turned your rockets off after reaching 60 miles altitude, you would simply fall back down.
That's why the space shuttle goes much faster than 76 mph. You have to be going at about 17,000 mph if you expect to avoid falling back to the earth when you shut the engines off.
2007-10-03 09:50:08 · answer #1 · answered by RickB 7 · 2⤊ 0⤋
First you must define 'outer space' here. If you consider the ISS orbit is outer space, then it is about 200 miles. So the time needed is : t= 200/76, appro. 2.76 hours.
This question has nothing to do with escape velocity. Escape velocity is the initial velocity needed for an object to go off the earth without any rockets or engines of any kinds. There are two types of escape velocities : level I and level II. Level I (about 7.7km/s) the object will orbit the earth, Level II (11.7km/s) : the object will go to infinity.
2007-10-03 17:33:27 · answer #2 · answered by thlee 2 · 1⤊ 0⤋
You would reach outer space in not much over 4 hours.
This wouldn't put you in orbit but it would put you in outer
space.
Outer space starts where the atmosphere ends.
Orbital speed has nothing to do with it.
2007-10-04 10:22:20 · answer #3 · answered by Billy Butthead 7 · 0⤊ 0⤋
space is blue and birds fly through it...hahahaha space is everywhere!!!! however, if you mean outside earths atmosphere. then it would take you about an hour, give or take a few minutes...depending on who you ask. earths atmosphere is much more extensive than some people give it credit for. so i guess it depends on parts per billion of the atomic concentration of the atmosphere within earths gravitational field. most people just stick with 60 miles straight up!!!!! good luck i hope this helped!!!
2007-10-03 17:28:49 · answer #4 · answered by Bones 3 · 1⤊ 0⤋
I don't know where outer space starts. space starts around 60 miles from earth
2007-10-03 16:46:53 · answer #5 · answered by keeprockin 7 · 2⤊ 0⤋
escape velocity is 17,000 mph .. you wouldn't .. however if you mean to travel the distance into space, you'd take about 3/4 hour to reach 'real' space
2007-10-03 16:47:59 · answer #6 · answered by The old man 6 · 1⤊ 1⤋
never; there is a little issue called "Escape velocity"
2007-10-03 16:42:19 · answer #7 · answered by wizjp 7 · 0⤊ 3⤋