Space/Science — HabitableZone

Space/Science

Can we be “resourceful” on the Moon? (Part 1)

"While the resources of space have the potential to revolutionize spaceflight—giving us a much wider range of activities than are now possible, including habitation of other planetary bodies—discussions on various internet forums show that there is a lot of confusion and lack of knowledge about space resources in general and lunar resources in particular.
...
So, what is a “space resource?” In broad terms it is needed materials or energy derived from space itself. The value of space resources is immediately obvious; at transport and delivery costs exceeding $20,000 per pound to low Earth orbit, everything we find and use in space is one more thing we do not have to pay exorbitant costs to transport. For human spaceflight, consumables are heavy but absolutely necessary. This category includes air, water, electrical power, and rocket propellant."
http://blogs.airspacemag.com/moon/

On earth if you had a straight flat smooth road which was 1000 miles long, and you drove a car which got 50 miles per gallon, you would consume 20 gallon of gasoline. More than 19 of the 20 gallons of that gasoline would be used to overcome road friction and air resistance.
One advantage of space not mention much is that we could be use less energy. It's probably not mentioned much because rockets are such energy hogs- largely because rockets at the moment are required to lift their rocket fuel.
And it does require a lot energy to get to orbit.
The speed you need to stay in earth orbit is about 7.85 km/sec [28,260 kph/17,550 mph].

"The kinetic energy of an object is the extra energy which it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its current velocity. "
http://en.wikipedia.org/wiki/Kinetic_energy
Kinetic energy = 1/2 Mass times velocity squared

So the kinetic energy of 2 kg object in orbit travel at velocity of 7.85 km/sec
Is 7850 m/s times 7850 m/s is 61,622,500 joules
The kinetic energy possible from a gallon of gasoline is 130,000,000 joules.
So a 4 kg object in orbit has about the same amount of energy as one gallon of gasoline.
So roughly 3 kg of gasoline and 4 kg of oxygen would generated the same heat as a 4 kg
object which re-enters earth atmosphere. Or if you efficiently use the energy from 3 kg of
gasoline and 4 kg of oxygen combustion this energy could accelerate a 4 kg object to about
8 km/sec.

Going back to our 1000 mile long road. If it was instead a tunnel which was a near perfect vacuum and
you had track with magnetically suspended a car, then you could travel 1000 miles for less than a gallon of gasoline [traveling at 60 mph]. You could of course travel much faster than 60 mph- and would use more gasoline to accelerate you to these higher speeds- and btw you could recover some of the energy by using some kind of "regenerative braking"- maybe 1/2 of the energy you used. So one could travel at hundreds of mph for a distance of 1000 miles for around 1 or 2 gallons of gasoline [+500 mpg].
Using this setup, one could accelerate the 4 kg object to orbital velocity [8 km/sec] by using around 130,000,000 joules of energy [36 kw/h about $4 of electrical power or about 7 lbs of chemical energy- rocket fuel also about $4 of energy]. Though it is a bit difficult make something like this to work. My point is that in terms of energy use it could possible to get to orbit for little as about $200 worth of energy and maybe a ticket price per passenger around $500 to $1000.

This sort of thing would fairly hard to do on Earth, but on the Moon you don't need a tunnel to maintain a vacuum and there is no reason to travel at 8 km/sec on the Moon. The Moon circumference is just over 10,000 km- at 5 km/sec you travel to opposite of the Moon in 1000 seconds [16.7 minutes]
Probably taking 30 minutes to 1 hour to travel from one pole to the other would quick enough. But rather then put down all that track, one would travel suborbital.
And on the moon it would fairly easy to get +500 mpg for passengers and the similar type energy savings for freight.

So, it's likely that anyone reading this post has used more than 10 times the energy during one's lifetime then the energy required for that person to get to the Moon, and it's likely that lunatics would need to use about 1/10th of the energy per year than compared to earthlings at the present.
In terms of solar energy one generate about twice the total energy per solar panel anywhere on the Moon as one could on best places on Earth. In terms of nuclear energy is would not a problem on the Moon- the Moon could import nuclear waste. Lots of things require a vacuum to make on Earth- the silicon for solar panel as one example.
The only real kind of pollution one would have on the Moon would something causing the Moon to have an atmosphere. Though littering could unsightly and one could have indoor pollution.

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