If you could build a ladder tall enough
Discussion
t!thebraketester said:
northwest monkey said:
Genuine question - why use rockets then & not planes?
Because getting into orbit DOES require a great deal of power and speed. 17,000mph ish isn't it?
So basically, a flying object needs to be going "quite quick", but a bloke on a ladder could just climb into space?
'Orbit' is a bit of a moving target.
Consider Geo synch orbit, you are not moving in relation to the ground at all, but it takes a lot of energy to get up that far from earth and you need the escape velocity at first to get there
Basically anything going ~ 8-11 km a second is going to get out into orbit
Consider Geo synch orbit, you are not moving in relation to the ground at all, but it takes a lot of energy to get up that far from earth and you need the escape velocity at first to get there
Basically anything going ~ 8-11 km a second is going to get out into orbit
Funkycoldribena said:
Pvapour said:
You'd be a bit hungary after that kind of climb
Maybe take Turkey sandwiches?you could wrap some tinsle round the ladder as you go if the nano tubes would take the extra weight?? (serious question
) this would also help aircraft avoid hitting you and keep H&S happy 
tuffer said:
Could you just climb into space? I know there is some ludicrous speed that rockets need to reach to escape the earths atmosphere but could you theoretically just climb through it on a very tall ladder?
It's nothing to do with "escaping the earth's atmosphere".Speed is needed to overcome the gravitational pull of the earth. If the rocket doesn't achieve the correct speed, as soon as the it stops thrusting, it will fall back to earth.
In the late 1940s and early 1950s, the US launched adopted German V2s to very high altitudes. One even reached an altitude higher than the International Space Station orbits today. But the V2 never reached a speed higher than about 4,000 mph so, once the rocket motor cut out, the missile fell back to earth.
deadtom said:
northwest monkey said:
Genuine question - why use rockets then & not planes?
because planes need air to fly through...However, the notion of an aero-spaceplane is not out of the question. In a sense, the NASA Space Shuttle was such a device, although it only became a true aeroplane after it had re-entered the atmosphere and was travelling in dense enough atmosphere where it could fly as a glider and its aerodynamic devices (wings, tailfin, rudder and elevons) could be used to control it
The main problem is having an engine that can function as a jet engine when flying in the atmosphere and also function as a rocket once there is not enough atmosphere to provide oxygen for combustion to the engine. That is the problem that is being addresses by Professor Alan Bond and his Skylon/Sabre project.
Have a read -
http://www.reactionengines.co.uk/sabre.html
As I said earlier, to achieve orbit (or escape velocity if travelling away from the earth), the object you are putting into space has to achieve a phenomenal speed relative to the earth. For earth orbit you are looking at 17.500 mph and for escape velocity you are talking 25,000 mph. A jet engine cannot provide the thrust required to achieve these speeds and also, these speeds cannot be maintained within the earth's atmosphere as the heat generated as the vehicle punches through the air would just burn it up.
With a conventional rocket, the initial acceleration of the rocket motors will get the vehicle up to about 5,000 mph and 20 miles or so altitude at which point the atmosphere starts thinning dramatically. Once out of the denser layers of the atmosphere, the acceleration can continue without aerodynamic heating being an issue.
northwest monkey said:
thebraketester said:
northwest monkey said:
Genuine question - why use rockets then & not planes?
Because getting into orbit DOES require a great deal of power and speed. 17,000mph ish isn't it?So basically, a flying object needs to be going "quite quick", but a bloke on a ladder could just climb into space?
CrutyRammers said:
northwest monkey said:
thebraketester said:
northwest monkey said:
Genuine question - why use rockets then & not planes?
Because getting into orbit DOES require a great deal of power and speed. 17,000mph ish isn't it?So basically, a flying object needs to be going "quite quick", but a bloke on a ladder could just climb into space?
Edited by thebraketester on Sunday 6th December 15:44
Edited by thebraketester on Sunday 6th December 15:44
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