Zero Point Native
Registered Senior Member
Proposal for large scale habitat on Mars.
- Thread starter Gawdzilla Sama
- Start date
Zero Point Native
Registered Senior Member
And then we also have that minor issue of the planet’s geo magnetic field. Our bodies most likely wouldn’t adapt in our current state and then we would probably just deteriorate and die in just a few months. So there’s that.
Gawdzilla Sama
Valued Senior Member
I don't care about the impossibilities, I was just speculating on the methodology. I went through this with some profs at Purdue "a few years ago". We had fun batting the idea around.
Yes, I have. Have you looked at pictures of the Grand Canyon? Much steeper walls.
Gawdzilla Sama
Valued Senior Member
(Check his phone.) Yeah, I've seen them. What's your point. Have you looked at the images Valles online? If so can you provide a link to the one you think supports your position?
Sure here are two. The first is an overhead shot of the whole area. Note that it looks sort of like some eroded canyons and then a whole lot of flat. The second is a cross section. Note that the walls don't look all that steep - and also note that the vertical scale is exaggerated 4:1. So it's 4 times flatter than even that image depicts.
Gawdzilla Sama
Valued Senior Member
And what's your problem with my proposal, you've haven't provided any reason for me to revise it at this point.
A few things.
1) Your proposal "covers" part of the Valles with plastic, getting 5 of the 6 sides for "free" because you can do it in a deep canyon. To do that you'd need a plastic cover 150 miles wide. I think it would be more practical to choose, say, a lava tube or a crater if that's the direction you want to go. Smaller and more material-efficient.
2) As I mentioned before I recommend you calculate the forces on that piece of plastic before you think that's a reasonable idea. Ever been to a big public aquarium? You know the sizes of glass/plastic needed to keep water in a 20 foot deep tank? Those are the sort of pressure differentials you'd be dealing with.
Gawdzilla Sama
Valued Senior Member
1) It doesn't have to go all the way across.
2) Inflated column, made out of the roof material, keeps the roof up.
This is not hard.
2) Inflated column, made out of the roof material, keeps the roof up.
This is not hard.
HonestJoe
Registered Member
All requirements are required, the ones I identified are key requirements is because they're location specific and don't have any real alternatives. Things like food, accommodation, power, infrastructure etc. are all equally important but have more potential flexibility in how they're met. This proposal is presenting some thoughts on addressing some of those requirements in a specific location, but if the key requirements can't be met there, it's a non-starter from the outset.
Gawdzilla Sama
Valued Senior Member
We also didn't discuss infant care on Mars. Bad us.
Gawdzilla Sama
Valued Senior Member
And if the key requirements aren't met then OBVIOUSLY it's a non-starter UNTIL we find a way to do that. I personally wasn't planning on starting this on Jan. 2nd., 2025.
Why not use a crater where it COULD go all the way across?
That's not the problem. Again, just do the math.
Gawdzilla Sama
Valued Senior Member
Because a crater has limited space for expansion compared to the V. M.
As for doing the math. I thought about it, but it didn't add up.
As for doing the math. I thought about it, but it didn't add up.
Go to the next crater over, then.
OK. For a very very simple approach:
Assume you pressurize to about 8psi. Plants will have no problems at that pressure. Some animals will do OK, especially species like mountain goats that have adapted to higher altitudes. Humans will do OK either with an oxygen mask or a 30-40% O2 concentration (severe fire risk but let's be OK with that for now.)
Let's take a small section of the canyon; say 100 by 500 miles of plastic. That's 2x10^14 square inches. Total force 1.7x10^15 pounds. That's about 2 quadrillion pounds of force on that plastic trying to push it upwards.
For reference, the entirety of Mt. Everest, from sea level on up, weighs about 350 trillion pounds. So your plastic would have to support 6 Mt. Everests sitting on them (but from the other direction.) How thick would that plastic have to be?
Let's say you put anchors every mile. That's a lot of anchors - 50,000 of them to be exact. Each one would have to pull downwards with a force of 16 million tons. The strongest bridge anchor ever built on Earth - for the Akashi Kaikyo Bridge in Japan - can withstand 132,000 tons. So you would need 120 of those for every anchor. Total of 6 million anchors of that size just to hold down the plastic - even if somehow the plastic could take the strain.
It really is. Hence it's a good idea to start smaller.
Gawdzilla Sama
Valued Senior Member
I didn't say do the whole damn valley. Jesus, people.
As for "do the math", we don't know enough to do the math yet. Speculative, not ready for the concrete trucks to come in.
As for "do the math", we don't know enough to do the math yet. Speculative, not ready for the concrete trucks to come in.
Gawdzilla Sama
Valued Senior Member
Yes, and Red Thunder is still on the drawing boards. There are issues to deal with IF it's going to work. And we can't "Do the math" until we know what the numbers are. I've gone over these and other issues, quandaries, PFMs, etc., a few times. Had fun running this past the boffins at Purdue over lunch.
Right. I was talking about a small part of the valley. The whole valley is 300,000 square miles; the structure I talked about was only about 1/6 the size of that.
The basics (pressures and forces) are well known. There are untold details, of course - but if the basics don't support the concept, the details aren't going to matter.
Some alternatives:
You could do a double wall plastic membrane and then fill the area between the membranes with water, so the weight of the water would provide the downforce needed. You'd need ~600 trillion gallons of water to offset the pressure, which is a layer of water about 30 feet thick. The good part about that is that it would provide excellent radiation protection. The bad part about that it will freeze almost instantly, and not a lot of light is going to get through 30 feet of ice.
There is enough water for this on Mars, although it might well be very hard to get to.
You could do a very small glass window over a very large lava tube, then use mirrors to send sunlight down into the hole.
Or you could do a very small glass window over that very large lava tube, and then use a nuclear reactor to generate power for grow lights. The waste heat from the reactor would be useful for heating as well.
Gawdzilla Sama
Valued Senior Member
Read the first line. Ciao.