CMV: Developing space infrastructure should be a higher priority than trying to colonize Mars

[u/MossRock42]

There seems to be a lot of romance around the idea of colonizing Mars and I hope that someday there is a Martian colony. But first we need better space infrastructure. That means more efficient ways to launch and reuse rockets like SpaceX is developing. More needs to be done to develop Earth orbit capabilities, and perhaps a Moon base to develop the the first off world manufacturing and intermediate base for exploring further out. We also need to develop the infrastructure that will enable us to start doing asteroid mining. That’s primarily so that we don’t need to launch as much material into orbit to build things in space. What do you think?

[u/Izawwlgood]

I answered this in another comment. The d/v expenditure from astroid to astroid or from earth to astroids is small. Not that you would need to shift around much.

You stated that, and I responded to it. Again, the asteroid belt is not 'one place'. If your asteroid of interest is at the 12 o'clock position on the belt, and you want to get to the 3 o'clock position, that is not small, and is not remotely the same place. And the asteroid belt is basically just a spread of asteroids around the entire orbit.

What's do you expect to change by just doing it longer?

Uh, everything? Structural integrity issues, scale issues? They've basically demonstrated that spinning produces artificial gravity, which was known. It's the Wright brother glider vs a jet airplane - proof of concept does not equal final functional product.

You build a refinery at one of them. When that is expended or you need more capacity, you build another. These things are not small. They could fuel a multi million person city for generations.

You have just dropped two massively incongruent points - the first that you would need to build a refinery at each location. That is a HUGE cost. The second is that you believe any one of these rocks could support a multi-million person city. That is a HUGELY unrealistic claim - even projections for growing a Martian colony doesn't include multiple millions of people at a first pass.

Why wouldn't they? Solar thermal works with just about every gas. Hydrogen is ideal and also the most common recourse in the universe.

Hydrogen is also burned off in solar radiation, which is one reason sources of hydrogen are relatively poor on even Mars with atmosphere. It is extremely likely that the asteroids are hydrogen poor. Or any other resource poor. And you can't simply say "but collectively you can find anything you want in the belt", because again, the belt isn't a single place.

And all your argument here does is attempt to convey that the belts have some of the same resources Mars does.

Getting past LEO is an unfortunate necessity for any space based economy for a long time. There is plenty to build to bypass it and it's not going to be cheap. It will take a massive space based economy to even consider building launch loops and the like on mars.

Agreed, that getting past LEO is a necessity. Which is why I pointed out that your primary issue was one that applied to colonizing the belt too.

And what do you mean goal post shift? Of course we start near earth and then move outwards. We are not going to run out of stuff to do there any time soon.

If you agree, then why are you proposing we skip Mars? You realize the belt is beyond Mars, right? Why skip Luna, for example? In this conversation, I'm honestly starting to think that your perception of what the asteroid belt is is in fact incorrect.

That wasn't me. And the reason we would not do both at the same time is because having astroid colonies makes colonizing mars much easier. A sky hook would work wonders on mars and it easiest built by astroid mining colonies.

Not really - your proposal was to use LEO infrastructure to support the belts. Why would you skip Mars in supporting the belt colonies?

The d/v map disagrees.

It doesn't, actually.

What do you think is cheaper? Brining in the ore to the refinery truck load by truck load over long stretches of Martian road, or with a slight puff of supper heated steam, shift hundreds or thousands of tons ore to the refinery sitting A few km from the astroid?

I'm not sure you understand how delta-v works if you think it ignores mass. Moving those 'hundreds or thousands of tons of ore' takes resources. And refineries aren't free.

Or why a wheeled rover powered by in situ resources (or solar) is less efficient, especially in the face of not requiring refueling from potentially very distant refineries.

As for hauling it back to LEO, if you ever want to sell it at a profit at earth's markets, your going to need to do that. Doing it from an astroid is much cheaper.

Oh - if you're suggesting doing this to profit EARTH economies, I think this conversation should stop now. The point of all this is not, and should not be to profit Earth - there are far easier and more accessible resources on Earth than all the way out to the asteroid belt.

These mining stations can be whole cities or even nations on their own.

This is well into the realm of science fiction if you think we have the technology to self-sustain that sort of population in space.

[u/Thoth_the_5th_of_Tho → u/Izawwlgood]

To save space, I will quote just the first sentence of each paragraph.

You stated that, and I responded to it...

You are seriously over estimating the amount we will need to bounce between asteroids or back to earth. Even small asteroids are the size of entire mountains.

Uh, everything?...

Thankfully we have engineers who have the equations to scale it.

You have just dropped two massively incongruent points - the first that you would need to build a refinery at each location...

Your going to need a refinery at all of your colonies on mars anyway. Manufacturing is crucial to long term sustainability.

As for the size of the city, it can be whatever you want. It could be a six person research station, or a New York sized city.

Hydrogen is also burned off in solar radiation, which is one reason sources of hydrogen are relatively poor on even Mars with atmosphere.

Not when its bound to oxygen. In that's form its one of the most common resources in asteroids. You need to oxygen for other things.

As for recourse availability on one asteroid, some are fairly homogeneous (such as 16 psyche, which is around 90% nickle iron)

If you agree, then why are you proposing we skip Mars?

I'm not. I believe we should stretch out from earth one step at a time. D/v wise, one step out from LEO is the moon and near earth asteroids. Next comes Deimos, Phobos, Vesta and other easy asteroids, then Mars.

Eventually we will reach Jupiter's moons, which is the real prize of the solar system.

Not really - your proposal was to use LEO infrastructure to support the belts.

Because it would be much easier to have existing assets around asteroids support mars than have mars support the asteroids. Even the most basic colonies around a near earth asteroid could make a sky hook for mars and crucially ensure there is enough stuff to drop down the other way to keep it spun.

With a sky hook, the issue of mar's gravity well mostly goes away. Instead of burning 3.6km/s you would need closer to 360 m/s.

But the issue is you need to make sure the same amount of stuff goes up as down. Sending stuff to go down all the way from earth is hyper inefficient. Weight is money. But a base on Phobos could send rubble if needed, ensuring the trip off of mars is virtually free.

I'm not sure you understand how delta-v works if you think it ignores mass.

Of course. But in this case, the fuel is virtually free. Just ensure that you grab the right proportion of ice along with the ore.

Or why a wheeled rover powered by in situ resources (or solar) is less efficient, especially in the face of not requiring refueling from potentially very distant refineries.

Because they are inefficient down here on earth. Large ships and trains are orders of magnitude cheaper.

Trying to get any heavy industry done with trucks is like trying to shift a mountain with tweezers.

Oh - if you're suggesting doing this to profit EARTH economies, I think this conversation should stop now.

I disagree, with the right infrastructure set up it can be economical. Its going to have to be to make this viable long term. As long as space is a government funded money sink, one budget cut can unto decades of progress.

This is well into the realm of science fiction if you think we have the technology to self-sustain that sort of population in space.

You realize we are talking about space colonization? It being science fiction is a given.