Elon Musk wants to populate Mars with 1 million people to save humanit

Dook · 2016-10-08 16:17:26

Tom Kalbfus wrote:

kbd512 wrote:
Dook wrote:
...

Well, normally you're burnt or buried after you die..
That is third person, bet you don't know what happens first person when you die, no one does! Knowledge and belief are not the same thing.

No one knows what happens when you die? Let me ask you something, how did Einstein figure out E = MC2? He wasn't exactly highly educated and even so it was way beyond the theories of his time.

How did that happen? He figured out something that no one else knew, right?

So, we have proof that some people DO know things that others don't.

Tom Kalbfus · 2016-10-08 18:49:15

Einstein wasn't the one who discovered that the speed of light measured as independent of the speed of the observer and always constant, that was discovered by an experiment run by Michelson and Moorely.
https://en.wikipedia.org/wiki/Michelson … experiment. With that information, it was only a matter of time that the equation E=MC^2 would be deduced. If not Einstein, someone else would have figured it out, Isaac Newton could have done it, if he was given that information, he is the father of Calculus after all!

SpaceNut · 2016-10-08 20:20:22

Its understanding that leads the way to the unknown.....
The ability to use what we have in another way is much the same as we look to understanding the known as a way...

http://isru.nasa.gov/Propellant_Fuels_M … Waste.html

One example of this is to convert plastic packaging, food scraps, and human waste into fuel. The process being studied thermally degrades plastic in the presence of oxygen producing CO2 and CO. The CO2 and CO gases are then reacted with hydrogen over catalyst (i.e. Sabatier reaction) producing methane (CH4), a potential propellant fuel.

All to which this is something that I have said before is to use the waste stream to our advantage when it comes to mars.....

kbd512 · 2016-10-09 19:18:14

Dook wrote:

So you're plan is to travel around Mars collecting dry ice, somehow store it, bring it back to base, then put it in some other device that warms it and then pressurizes the CO2 just so you can increase the inlet pressure to the MOXIE and get a little more production? How much more production do you get for all this? Since oxygen is critical you're going to need at least three MOXIE units anyway.

My plan is to scoop up regolith, seal the container it's been scooped up in, and then heat the container to bake out the water. The temperature required to do that is far lower than the temperature that MOXIE operates at, which is approximately double the temperature required to melt zinc.

A rover driving slowly, dragging a regolith collection bucket through the regolith, and then closing the regolith container after it is full of regolith is not any sort of miracle technology that requires years of development. From actual testing on Mars, the water content in the regolith ranges from 2% to 60%.

Let's say that the average regolith has 2% water content and the rover has a bucket that stores .5 cubic yards of regolith and only recovers 50% of the water obtained because the seal on the bucket is not perfect, some water can't be baked out, etc.

From numerous samples obtained on Mars, the average Martian regolith density is 1.52 g/cm^3 or 0.054913493184585 lb/in^3.

.5 cubic yard = 23328 cubic inches

.5 cubic yards of regolith would then weigh 1281 lbs on Earth or 487 lbs on Mars

1281 * .02 = 25.62 lbs of water, but we only get half of that, assuming we lose half, so we extracted 12.81 lbs of water

If we "scoop" 3 times per day, that's 38.43 lbs of water per day, or approximately 4.6 gallons.

At 5% water concentration and three scoops per day, that's 96 lbs or 12.5 gallons per day. Obviously water content will vary, but expecting 5 to 10 gallons of water per day from three baking operations is not unreasonable. The technology can also be demonstrated here on Earth using a vacuum chamber.

Although oxygen is heavy, water is heavier still and humans use more water per day than oxygen.

Dook wrote:

You're concern is that the MOXIE uses 168 watts so two of them would exceed one RTG's output? I thought you were going to use the nuclear reactor?

You wanted to use a RTG for Dook Direct. I told you why I wanted to use a fission reactor, which is not a RTG. My reasoning is entirely focused on power requirements for sustaining human life. Current RTG technology is exceptionally poor at converting heat from radioactive decay into electricity and Pu238 decay doesn't produce nearly as much heat as fissioning U235.

1 gram of fissioning U235 produces 1,000,000 watts

1 gram of Decaying Pu238 produces .54 watts

The MMRTG's flown on Curiousity produce 2kWt (2000Wt) and convert that to .11kWe (110We). That means slightly more than 5% of the thermal energy is converted into electricity. If the theoretical thermionic converter that German and US universities are working on ever achieves the 40% theoretical conversion efficiency in overcoming the space-charge problem, then a RTG employing this theoretical thermionic converter could produce .8kWe (800We) using the same 4.8kg of Pu238. Even if the RTG tech ever advances to 40% thermal-to-electric conversion efficiency, you're still looking at 8% of the output of a very small fission reactor like SAFE-400.

SAFE-400 produces 400kWt (400,000Wt) and converts that to 100kWe (100,000We). It's thermal-to-electric conversion efficiency is just 25%. That's still pretty awful, but refer back to the amount of energy produced by fissioning a gram of Uranium.

People don't simply suck in oxygen. They also need water (for drinking and hygiene), heat exchange (to regulate habitat temperature), atmospheric scrubbing (to scrub CO2 and other trace contaminants), and computers to monitor the systems that perform those functions for them.

How much electrical power will all life support functions require in Dook Direct?

Collecting and electrolyzing water to produce oxygen has already been proven to require less electrical power consumption. This is not guess work on my part. NASA has flown OGS on space aboard ISS and actually uses this system to produce oxygen for the astronauts living on ISS from water (collected from human waste products).

Using MOXIE is not a big deal in an energy-rich environment. In an energy-poor environment, you have to decide between producing oxygen, water, and heat. You need all three. How long can the astronauts go without one or two of those three if the solar panels quit providing power in a dust storm and the RTG can't provide equivalent backup power.

Dook wrote:

Would I have an exploration team of four? Zubrin recommended a crew of four. I think a crew of three would be better, one to stay back at the Mars Hab while the other two go out in the rover to explore. And then when it's time to leave all three get in the Long Range Rover to go to the launch rocket. My idea of exploration comes way before settlement while some of you want them both at the same time.

So, basically you want to do Dook Direct, because Dook's plan is not Mars Direct.

Dook wrote:

If I worked with several hundred people would I remember their names? Yes. You don't look at people's name tags except when you're new, it doesn't take long until you recognize faces. If a stranger comes in without a name tag then you just ask them their name.

If you have time to do that, great. Sometimes you don't.

Dook wrote:

NASA has never had a good vision for it's own future. Their small rovers on Mars are fine but they should have jumped all over Mars Direct when it was proposed and instead they backed off because it didn't use the Space Shuttle army and it wasn't their idea.

Do you mean they are not goal-oriented or haven't achieved any goals that you agree with?

Dook wrote:

If you want to deliver a big payload you need a big rocket? Then why not just build a rocket twice the size of ITS?

ITS was sized to max out the ability of the pad to support the weight of the rocket.

Void · 2016-10-09 19:29:20

kbd512,

At the 2% value, do we think that the water is bound to salts in the soil, or to minerals. I am interested in what level of heating it will take to get a reasonable amount of water from the soil, because even at the equator, I believe that there is at least the 2% you mentioned.

kbd512 · 2016-10-09 22:16:40

Void wrote:

kbd512,
At the 2% value, do we think that the water is bound to salts in the soil, or to minerals. I am interested in what level of heating it will take to get a reasonable amount of water from the soil, because even at the equator, I believe that there is at least the 2% you mentioned.

The water is primarily a very salty brine and also includes some nasty contaminants, of the kind that the Paragon IWP was intended to process. That's pretty much what I expected. Despite the actual water content being much higher in some places, I'd wager that the average regolith water content is around 5%, which corresponds to a very dry desert.

The poles are probably the only exception, but it's cryogenically cold there and a nuclear reactor would be required just to provide enough heat to keep equipment from freezing. After the exploration phase is complete, a robotic water mining operation set up at the poles would use small fission reactors and tracked vehicles to transport processed water to the colonists for consumption.

Here's the proof-of-concept for water extraction:

Extraction and Capture of Water from Martian Regolith Experimental Proof-of-Concept by NASA Glenn Research Center

Water quality:

Water and chlorine content in the Martian soil along the first 1900 m of the Curiosity rover traverse as estimated by the DAN instrument

I don't think people understand how much water, oxygen, and nitrogen is lost during EVA's. NASA wants daily EVA's on Mars. That means MCP suits. That means sublimation of perspiration into the near vacuum of the Martian atmosphere. That means massive water loss. The atmospheric losses from decompressing a compartment every single day is substantial, but the water losses are a game changer.

Last edited by kbd512 (2016-10-09 22:21:14)

Void · 2016-10-09 22:47:23

Thank you very much kbd512. For a long time I have been trying to understand how much energy was required. If I understand correctly, 60 degC might get quite a bit of moisture out of most regolith?

This is one of my favorite kinds of Regolith:
http://www.nasa.gov/feature/jpl/nasa-ma … and-dunes/
pia20168-figa_sol-1176ml05329_scale.jpg?itok=NLrj788T

https://en.wikipedia.org/wiki/Ore_resources_on_Mars

Dark sand dunes are common on the surface of Mars. Their dark tone is due to the volcanic rock called basalt. The basalt dunes are believed to contain the minerals chromite, magnetite, and ilmenite.[39] Since the wind has gathered them together, they do not even have to be mined, merely scooped up.[40] These minerals could supply future colonists with chromium, iron, and titanium.

So, would I be wrong to suppose that in addition to;
Chromium
Iron
Titanium
Basalt

Perhaps processing could provide water of significance, and even salts which may have traces of other things needed.

???

The dune material will likely be much easier to process by a roving machine, then would be many other types of regolith, in my opinion.

I like sandstone as well, but of course that is more of a solid material. Not suitable to your intentions, of a rover.

Last edited by Void (2016-10-09 22:59:59)

kbd512 · 2016-10-10 00:08:26

Void wrote:

Thank you very much kbd512. For a long time I have been trying to understand how much energy was required. If I understand correctly, 60 degC might get quite a bit of moisture out of most regolith?

Void,

Yes, but the temp could be as high as 300C. It really depends on what the water is bound to. The quantity of water we can extract can be increased by increasing the temperature and/or lowering the pressure, but you don't need that much heat to extract most of the water in a near vacuum and you could optimize heating by increasing the surface area of the heating element by combining the heating element with the roto-tiller from the experiment. I would make the tiller the heating element in the next experiment and fully embed it in the regolith simulant.

You may recall that I proposed doing this in my nuclear powered rover a year or two back. It looks like someone has finally performed an experiment to demonstrate the feasibility of what I proposed. I'm sure I wasn't the first person to think of this, but it made sense to me at the time as a way to replenish water and oxygen lost during daily EVA's. In the light rover topic that SpaceNut started, we spent a considerable amount of time determining power requirements for life support. The use of water reclamation from Martian regolith and ionomer membrane water reprocessing figured heavily into the viability of my solar powered light rover concept, too.

GW Johnson · 2016-10-10 16:51:50

Compare 0.7 gallons of water out of 0.5 cu.m of regolith (2% water by volume) scooped up, to what you might get up a well into a massive buried ice deposit, with nothing more than steam injection. Especially if you must heat to 300 C to free it.

Even if 90% of the energy in the steam is lost to heat transfer into Mars, that's something like 90-100 BTU/lbm available to melt ice at 540 BTU/lbm, plus whatever pulls the solid up from its equilibrium temperature. Call it 600 BTU/lbm for a round number. Each pound of steam sent down the well produces about 1/6 lb of liquid water. Or maybe more. I dunno. Maybe less.

1/6 lb water is about 0.02 gallon. To get 100 gallons of water, you need around 5000 lbm of steam at that ridiculously-low extraction efficiency, which comes from about 600 gallon of water you need to get started. At an energy cost in the vicinity of 500,000 BTU for that 100 gallons of water = about 475 watt-seconds = 0.13 watt-hr. Tain't that many watts, is it?

I like the idea of drilling into a massive buried glacier a lot better than harvesting low-concentration water out of regolith. Select the "right" place, and you have one. And you need only a drilling rig and a steam generator to retrieve it. Sort of like "fracking", actually.

GW

Last edited by GW Johnson (2016-10-10 16:59:10)

kbd512 · 2016-10-11 20:35:16

GW,

The intent here is to prove that no matter where we decide to explore on Mars, we can obtain the resources that are right under our feet and use them to sustain human life. We already have the technology to obtain and process the water. Baking a bin of wet regolith and collecting the water condensate is not rocket science. Six scoops a day provides more than enough water to sustain four people, even with daily EVA's.

We should explore the glaciers near the Hellas Basin first, just to confirm that it is frozen H2O and to determine general water quality, but we really need the ability go wherever we want, whenever we want. If there are no major problems extracting water from regolith around the Hellas Basin, then we should proceed to drier areas. We're not just looking for water. We still need sulfur and metals for construction.

Mars_B4_Moon · 2022-09-12 11:28:50

Infographic of Artemis rockets (SLS & Starship) that will get us back to the Moon

https://www.humanmars.net/2022/09/artem … -will.html

,

https://www.tonybela.com/

SpaceNut · 2022-09-12 18:28:11

The going to the moon for starship is going to take qty 4 starship tankers, qty 1 starship taxi and qty 1 starship lunar lander. Sure, fuel amount from earth orbit to the moon is by far less than going to mars for the lunar lander but it's still going to take a lot of them even for 1 trip. Crew vehicle exchange is done while in earth orbit for both directions.

Mars_B4_Moon · 2022-10-05 04:45:31

SpaceX to upgrade Cape Canaveral pad for crew and cargo missions

https://spacenews.com/spacex-to-upgrade … -missions/

Elon Musk’s Cybertruck Destined for Mars

https://greekreporter.com/2022/10/04/el … ruck-mars/

Last edited by Mars_B4_Moon (2022-10-05 04:53:40)

New Mars Forums

Announcement

#101 2016-10-08 16:17:26

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#102 2016-10-08 18:49:15

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#103 2016-10-08 20:20:22

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#104 2016-10-09 19:18:14

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#105 2016-10-09 19:29:20

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#106 2016-10-09 22:16:40

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#107 2016-10-09 22:47:23

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#108 2016-10-10 00:08:26

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#109 2016-10-10 16:51:50

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#110 2016-10-11 20:35:16

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#111 2022-09-12 11:28:50

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#112 2022-09-12 18:28:11

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

#113 2022-10-05 04:45:31

Re: Elon Musk wants to populate Mars with 1 million people to save humanit

Board footer