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What Supports Apollo?
 
What Supports Apollo?
by 42 on 2007-Aug-08, 11:53:31 PM MST
 
This is a fantastic look at the Brobdingnagian proportions of the hardware required to launch Apollo astronauts into space. It's a fantastic look at the scale of the rockets and the buildings that house them and the fuel used. Even after so many years it still boggles the mind.

For instance, the Vehicle Assembly Building (VAB) was (and perhaps still is, if it still exists) the world's largest structure. It's large enough that you could play two football games on the ground. If you added additional floors to the building then the entire NFL's weekly schedule of games could be played in the building simultaneously. You could fit a half dozen Pan American Buildings into the VAB or a squadron of Hindenburg dirigibles.

The material used to make the road to the launch pad was partially mined from land nearby where there is now a large lake.

If anyone can give me permission then I'd be happy to type or scan this article in and post it here.

The closing quote from the article is interesting and I have no idea what to make of it. Apparently Arthur C. Clarke calculated that it only takes 1000 KwH of energy to lift an average sized man out of the Earth's gravitational field. That's not very much, so I'm not sure what's missing from that calculation. According to the article that's $20 in electricity costs in 1970 compared to $20 billion required for the Apollo program. Does anyone know how that 1000 KwH number was arrived at? It obviously takes many magnitudes more energy to launch a rocket to carry a human into orbit.
 
Re:What Supports Apollo?
by Anonymous on 2008-Jan-17, 8:22:12 AM MST
 
> it only takes 1000 KwH of energy to lift an average
> sized man out of the Earth's gravitational field

I guess this is a calculation of potential gravitational energy, which is given by the formula PE=mgh. This is the minimum theoretical energy that can do the job, if there are no losses other than doing work against gravity.

Suppose the astronaut is 72 kilograms in mass. Approximate gravity as 10m/s^2. Raise the astronaut to low earth orbit (say 100km). Multiply those together and you get 20 kilowatt hours, so I guess it's reasonable that 1000kWh would be enough to leave the earth's gravitational field (for all practical purposes).
 
Re:What Supports Apollo?
by Anonymous on 2007-Oct-01, 9:22:10 PM MST
 
"The closing quote from the article is interesting and I have no idea what to make of it. Apparently Arthur C. Clarke calculated that it only takes 1000 KwH of energy to lift an average sized man out of the Earth's gravitational field. That's not very much, so I'm not sure what's missing from that calculation. According to the article that's $20 in electricity costs in 1970 compared to $20 billion required for the Apollo program. Does anyone know how that 1000 KwH number was arrived at? It obviously takes many magnitudes more energy to launch a rocket to carry a human into orbit."

That is _IF_ the only thing being lifted out is an average man, but when you add in the rocket motors, fuel tanks, fuel, etc..., the costs to lift all of that start to soar.
Then you are adding in the cost to manufactur all those parts, and their support structures.

 
Re:What Supports Apollo?
by Anonymous on 2007-Oct-01, 9:21:07 PM MST
 
"The closing quote from the article is interesting and I have no idea what to make of it. Apparently Arthur C. Clarke calculated that it only takes 1000 KwH of energy to lift an average sized man out of the Earth's gravitational field. That's not very much, so I'm not sure what's missing from that calculation. According to the article that's $20 in electricity costs in 1970 compared to $20 billion required for the Apollo program. Does anyone know how that 1000 KwH number was arrived at? It obviously takes many magnitudes more energy to launch a rocket to carry a human into orbit."

That is _IF_ the only thing being lifted out is an average man, but when you add in the rocket motors, fuel tanks, fuel, etc..., the costs to lift all of that start to soar.
Then you are adding in the cost to manufactur all those parts, and their support structures.


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