Thought experiment: Can you build a station on the moon and launch it from there?

Given that you could use nuclear explosions to launch massive objects into space, I was wondering if there was another way to do it.  It may be the harder way, but it could have a better chance of making it past the anti-nuke crowd.

If we are going to have a space station, why not launch it from the moon, which requires only 15% or so of the energy?

We want to spin up our space station, so lets figure that out first.

Using the formula below, I experimented with several combinations of radius and rpm by using a spreadsheet.



Here are the results:

As you may notice, increasing the radius doesn't move the g's very fast, but rpm does.  Unfortunately, humans can't tolerate rpm's too much above 6 and most can tolerate 2 rpm.

Since I want to make the space station as small as possible, but large enough to do something useful, I'm going to select a 90 meter radius at 2 rpm.  This will give us a Martian like gravity of .40 g

I want to build the station on the moon and launch it from the moon using solid rockets which make use of the aluminum and oxygen which is so abundant there.  Hopefully, we can keep the mass down to a minimum.

The station will be in the shape of a torus ( think do-nut).  There was something I blogged about which was about how to make an extruded tube like structure on the moon.  I would figure an aluminum skin of sufficient thickness will give us a stiff enough structure, with a lightest possible weight.

But it may not give us enough protection from the harsh radiation in space.

Let's make it a double hull, and fill in the gap with water.  We may have to skimp on the water.

Let's divide the station into sections so that if one part of the station starts to leak, we can isolate it and possibly repair it before we lose all of our air.

Let's make it eight feet in diameter.  I don't know if an extrusion device could make it that big, so we have to keep it small as possible.

Let's make it and inch thick for each side of the hull, plus a foot thick of water.

That seems like too much as the weight will begin to get out of hand.

Luckily, the mass comes out to 324k pounds.  That means relatively small boosters like on an Atlas V could boost it into orbit.  The trick would be to make the boosters on the moon and attach them to the station.

In order to outfit the internals a bit would require more weight.  You wouldn't launch crew with it.

You'd also need access and so forth.  Plus a docking area.

Let's say it all doubles the weight.  We could still comfortably launch it using relatively small boosters in my opinion.


Update:

Come to think of it, it may be easier to just use methane and lox.

Update:

Ooops!  Too soon to post on this.  I found a significant error in the mass calculations.  It will be much heavier.

Probably about 4 or 5 times heavier on a rough guess.

Update:

You'd need to downsize to maybe a 50 meter station and spin up to 3 rpm.  It still be several times heavier than my original calc.

Other considerations would be the stresses and strains on the metal.  It may not be strong enough for what is being "attempted" here.

If such is the case, the water could wait until you get into lunar orbit.

Update:

With those thoughts in mind, you could still launch it without the water and with a powerful nuclear rocket.

By the way, this is starting to look a little iffy.

Update:

This is designated as a series now.  Consider this as part 2.  Part 1 was the previous post to this.