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#1 2021-01-10 09:13:46

tahanson43206
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Registered: 2018-04-27
Posts: 7,325

Mount Everest Base Station Mars Habitat Simulation Site

This new topic is offered in hopes there is interest in testing the ideas of RobertDyck (and others) for the ideal atmosphere to be created and sustained in habitats on Mars, as well as in the open spaces of the Large Ship which is under preliminary development in the Large Ship topic.

I invite RobertDyck (in particular) to contribute a post to this topic, re-stating the mixture of gases he recommends, and the pressure to be maintained, as well as the reasons for the recommendation.

Links to the related posts in other topics would work as well, and less typing would be involved.

RobertDyck has identified a possible location for a Mars Habitat Simulation on the slope of Mount Everest, at an existing base camp.

There are many advantages to this proposed site, not least of which is the existing infrastructure created to support Mount Everest climbs.

(th)

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#2 2021-01-10 10:05:45

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 23,094

Re: Mount Everest Base Station Mars Habitat Simulation Site

reposts as to development of topic

tahanson43206 wrote:

Still on the subject of food preparation at Mars Habitat pressure, here is a snippet that Google came up with .... I'd been getting all sorts of unrelated guesses (by the AI) as to what I was asking, but in this case, the guess included the exact information i was seeking ...

NWS JetStream - Air Pressure
www.weather.gov › jetstream › pressure
Therefore, the air pressure is the same in the space station as the earth's ... level from one location to another, especially when the elevations of each site differ. ... Weather maps showing the pressure at the surface are drawn using millibars. ... So, while the average altitude of the 500 millibar level is around 18,000 feet ...

I've been looking for a location on Earth where the proposed Mars Habitat pressure (and the corresponding Large Ship pressure) could be tested in safety on Earth, without having to invest in expensive vacuum equipment.

It would appear that a mountain that reaches 18,000 feet is a candidate location.

Something that relates to this is the observation I noticed in several citations that pressure at a mountain top varies with the weather, just as it does at sea level, but the range of variation (apparently) can be more extreme.  Several citations made the point that pressure at a location (such as a mountain top)_is also determined by temperature.

A Mars habitat, or the Large Ship would (presumably) be engineered to try to hold pressure and gas mixtures to a fairly tight specification.

Apparently there are only two mountains in the United States that meet the measure, and they are both in Alaska ...

Home > United States > United States Geography > Mountain Peaks in the United States Higher Than 14,000 Feet

Cite
Mountain Peaks in the United States Higher Than 14,000 Feet

The following table lists the mountain peaks in the U.S. that surpass 14,000 feet, along with their height and their state.
Name     State     Height
(ft.)
Denali 1     Alaska     20,320
Mt. St. Elias     Alaska     18,008
Mt. Foraker     Alaska     17,400
Mt. Bona     Alaska     16,500
Mt. Blackburn     Alaska     16,390
Mt. Sanford     Alaska     16,237
Mt. Vancouver     Alaska     15,979
South Buttress     Alaska     15,885
Mt. Churchill     Alaska     15,638
Mt. Fairweather     Alaska     15,300
There are quite a few more in this list ...

Here is a snippet from a table of mountains in Canada ...

Rank     Mountain peak     Province     Mountain range     Elevation     Prominence     Isolation     Location
1     Mount Logan[1][2][e]      Yukon     Saint Elias Mountains     5956 m
19,541 ft     5247 m
17,215 ft     623 km
387 mi     60.5671°N 140.4055°W

2     Mount Saint Elias[3][4][f]      Alaska
Yukon     Saint Elias Mountains     5489 m
18,009 ft     3429 m
11,250 ft     41.3 km
25.6 mi     60.2927°N 140.9307°W

3     Mount Lucania     Yukon     Saint Elias Mountains     5260 m
17,257 ft     3080 m
10,105 ft     43 km
26.7 mi     61.0215°N 140.4661°W

If Mount Saint Elias had a visitor cabin at or near the summit, it could serve as a test site for Mars Habitat cooking.

The cold of the environment would be a reasonable match for the Mars environment as well.

Edit: I listened to the City State competition presentation again (Video 35) and caught another aspect of cooking to think about ...

The presenter offered the suggestion that taste may be impacted by reduced atmospheric pressure.  I've not heard of that before.  My general impression is that meals served on air liners at altitude are as enjoyable as they are at sea level.  Still, it is probably worth keeping the possibility in mind. 

Edit#2: From the Wikipedia citation on Mount Saint Elias ...

Mount Saint Elias is infrequently climbed today, despite its height, because it has no easy route to the summit and because of its prolonged periods of bad weather (mainly snow and low visibility).[citation needed]

It might be a whole lot simpler to just make a vacuum chamber in a nice location at sea level.

On the other hand, a test kitchen ** could ** be delivered to the top (or near the top) of the mountain, and personnel could be airlifted in and out.

Google came up with this:

Turbine-engined helicopters can reach around 25,000 feet. But the maximum height at which a helicopter can hover is much lower - a high performance helicopter like the Agusta A109E can hover at 10,400 feet.

Oh well !!!

(th)

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#3 2021-01-10 10:07:10

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 23,094

Re: Mount Everest Base Station Mars Habitat Simulation Site

RobertDyck wrote:

Pressure cooker recipes, with experimental results. Includes mashed potatoes and baked potato.
Instant Pot & Pressure Cooker Recipes

tahanson43206 wrote:

For RobertDyck re #561

Thanks for the link to the web site this interesting couple put together!  I hope there are forum readers who are inspired to try some of those recipes!

I find myself bemused by the constant use of the word "Instant" when most recipes seem to run for an hour or more, but figure that might represent a reduction of cooking time without pressure.

In any case, it ** does ** seem reasonable (to me at least) to suppose cooking with pressure cookers would not be a major problem for ship kitchen staff or for Mars residents.  However, you are (as far as I know) the first person to take the issue on, in the context of either transportation to Mars, or living situation there.

I have no experience with pressure cookers, other than having seen them in stores.  I would imagine that in the case of Mars, it might be possible to set the cooker to Earth standard pressure, so that cooking times would the same as the Earth recipe.

Here I am venturing away from the need for pressure equal to Earth, by asking (out loud since I don't know) if roasting might take the same amount of time in a 1/2 bar atmosphere as it does in a 1 bar atmosphere.

Moisture would leave the roast more rapidly than it would on Earth, and that might not be all that helpful.

I asked Google, and it came up with a site that appears to offer reassurance about roasting ...

https://www.eatright.org/homefoodsafety … -altitudes

Add a Quarter
Moist heating methods for meat and poultry, such as boiling, simmering or braising, will take up to 25 percent more cooking time. For example, if you are simmering a roast at 325°F that would usually take two hours to cook at sea level, that same roast cooked at high altitudes at 325°F would require 2½ hours of cook time. Increasing cook time does not apply to oven-roasted meat or poultry; oven temperatures remain unaffected in high altitudes. Use sea-level cooking instructions for oven baking.

Increase Cook Time, Not Heat
Hiking up the temperature while boiling foods will not cook food faster. The liquid will simply boil away more quickly and food will dry out. The temperature of a boiling liquid cannot exceed its own boiling point, except when using a pressure cooker. Instead, increase the cook time.

Cover Your Food
Retain moisture in meat and poultry products or any boiled food by tightly covering the pan during cooking. To continue to keep foods moist, cover dishes after cooking.

Use a Food Thermometer
To avoid undercooking or overcooking meat, poultry and leftovers, especially in a high altitude environment, use a food thermometer to confirm internal temperature.

High altitude influences all forms of cooking from using a fryer, pressure cooker or wok to microwaving foods. Consult the USDA Food Safety and Inspection Service's guidelines for safe cooking at high altitudes for specific instructions for various methods of cooking.


Tags HomeFoodSafety Four Steps Cook

There is an interesting hint there that even pressure cooker recipes need to be adjusted for altitude.

This digression could lead to an entire topic devoted to cooking at Mars Standard Habitat Pressure.

Such an atmosphere could be simulated on Earth, and recipes tested by experienced professional cooks.

Perhaps the day will come when it would make sense to invest in such a study.

Edit #1: ... A quick check with Google confirmed that the atmospheric pressure at the top of Mount Everest is well under half of sea level pressure.

That means that there are likely to be a number of sites around the world where exact matching air pressure is possible, between the 1/2 bar Standard Habitat Pressure recommended for Mars and whatever is found on land at a suitable site.

The only requirement would be to add enough oxygen to reach the 2.7 psi value recommended by RobertDyck.

(th)

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#4 2021-01-10 10:08:53

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 23,094

Re: Mount Everest Base Station Mars Habitat Simulation Site

RobertDyck wrote:

Cooking will be done indoors, at controlled temperatures. But there has been some work re cooking at altitude, you could Google that.

By the way, first location that comes to mind is Mount Everest base camp. Not the summit. I believe base camp has a building of some sort. Altitude 5600 metres = 18,372 feet.


Water boils @ 81.01°C = 177.88°F at 18,000 feet.

tahanson43206 wrote:

For RobertDyck re #578 ... Now! You're talking!  Excellent!  And! The government of Nepal is likely to welcome tourist dollars.

And! (inspired by movies of Everest climbs) ... the aura of being a Mars training location might appeal to the people of Nepal.

It ** should ** certainly appeal to the leaders of China, who are already thinking about setting up shop on Mars.

***
Regarding your point about cooking indoors .... somehow you've missed the point I tried to make earlier ...

The "indoors" you've specified will be maintained at .5 bar.  The cooking will be done at the equivalent of Earth 18,000 feet.

A pressure cooker might be able to bring pressure up to Earth sea level, which would allow for Earth equivalent cooking times where pressure is a factor.

I'm still not clear on how pressure affects roasting.  One reference I found suggested it is NOT a factor.

It would be helpful for your chef advisor to know what (they) are going to be dealing with.  It is a minor challenge to be operating at only .38G.  It is likely to be much more than a miner annoyance to be condemned to .5bar for ** life **.

(th)

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#5 2021-01-10 10:11:08

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 23,094

Re: Mount Everest Base Station Mars Habitat Simulation Site

The location gives more than an experiment for cooking and atmospheric pressure as it also allows for the air mixture testing required for Mars in a simulated environment.

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#6 2021-01-10 11:33:18

tahanson43206
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Registered: 2018-04-27
Posts: 7,325

Re: Mount Everest Base Station Mars Habitat Simulation Site

For SpaceNut re #5 (and earlier reposts) ...

Thanks for your support of this new topic ... It should be of interest to Dr. Zubrin at some point.

One of the recent convention videos mentioned the 1/2 Bar atmosphere as a standard they would adopt for their habitats.

This was (no doubt) without their having been given a chance to read the writings by RobertDyck ... It's interesting to me to see at least two independent minds arriving at the same conclusion.

A key difference is that whereas RobertDyck is very specific about the partial pressure of Oxygen he recommends, the video presentation was NOT specific. The presenter only indicated there would be enough Oxygen to the residents would be "comfortable".  "Comfort" on Mars (or in the Large Ship) would involve at least 2.7 psi.  The specific partial pressure recommendation by RobertDyck (as I remember it) was chosen so that when residents donned their Mars suits, the gas pressure inside the suit would be 3 psi of pure Oxygen.  As I remember RobertDyck's argument, if the suit leaks down to 2.7 psi, the resident would be back to habitat partial pressure.

I can easily imagine habitat residents playing with the Oxygen control, the way Earth citizens are wont to play with the temperature control in office buildings.

Edit#1: Come to think of it, Mars suit wearers might adjust the amount of Oxygen they experience inside the suit depending upon circumstances ... They might drop the pressure during periods of low activity, and raise it during active periods.

(th)

Last edited by tahanson43206 (2021-01-10 11:35:48)

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#7 2021-01-10 16:02:01

SpaceNut
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From: New Hampshire
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Re: Mount Everest Base Station Mars Habitat Simulation Site

Thats the pure oxygen atmosphere and that is bad due to fire risk.

Gw Johnson wrote:

If it was air (synthetic air) 20.9% O2 and 78.1% N2,  the oxygen mass percentage is 23.15%,  which means the nitrogen mass percentage is 76.85%.

So if earth is 14.7 psi and we are looking at a 1/2 way point then the mix still needs a simular 21% of oxygen ratio the half psi in that portion in the half some want the percentage to double to 42% but we desire just 3.0 psi of oxygen.

A 3.0/(14.7/2)= 0.4081... or 41%

Chose a mix of gasses to get to the PSI desired in argon, helium, nitrogen where the level of nitrogen is reduced to allow for no waiting to get into a space suit or to come back in.

https://sstsensing.com/o2-sensor-workin … -pressure/

But what matters is blood oxygen.

https://www.ncbi.nlm.nih.gov/books/NBK493219/

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#8 2021-01-10 18:34:32

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
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Re: Mount Everest Base Station Mars Habitat Simulation Site

Air mixture:
I start with a spacesuit designed for Mars, then ensure the habitat allows going outside in said spacesuit easily and quickly. That means zero prebreathing.

Partial pressure oxygen on Earth at sea level is 3.0782 psi. One post on the old forum from 1999 cited an Air Force study that pilots could breathe 2.5 psi pure oxygen indefinitely and continue to operate an aircraft if they had high altitude training. They found 3.0 psi pure oxygen was enough for anyone, not just those in their prime and without high altitude training. Ok, so use 3.0 psi pure oxygen for the Mars spacesuit. Dr Dava Newman of MIT said developing an MCP spacesuit for 20 kPa pressure is easy, 30 kPa is hard. Ok so use 20 kPa. Easy is good. And 3.0 psi = 20.684 kPa.

Extreme low pressure can cause a problem with lungs drying out. To prevent that use humidity. But high humidity can cause the visor to fog. Solution is a breathing mask like a jet fighter pilot so air over the eyes has normal humidity.

In the early days of Apollo, NASA intended to use 3.3 psi pure oxygen for spacesuits and 3.0 psi pure oxygen for the Apollo capsule. The justification was the suit could experience 10% pressure loss and it's still what astronauts are used to. They changed it, but the principle applies. So use 2.7 psi partial pressure oxygen in the habitat.

There's a ratio of maximum partial pressure nitrogen to total pressure of the lower pressure environment for zero prebreathe time. From diving decompression studies. I could look up the fancy name, but the number is 1.2:1. So that means for suit pressure of 3.0 psi, maximum partial pressure nitrogen in the habitat is 3.6 psi. I recommend just a little less to stay away from the edge of disaster, so 3.5 psi.

For more pressure you can add helium or argon. Earth's atmosphere is 0.9340% argon, so you're breathing it right now. Mars also has argon, so it's easy to get. There's a limit to argon as well, but we can stay well below that. I had used the ratio of N2:Ar found by Viking 2 lander, but modern Rovers found a different ratio. I hadn't thought N2 or At could vary in Mars atmosphere but it looks like it does. So just keep it simple, add enough so total pressure is 1/2 Earth at sea level. Earth has 14.69595 psi so 1/2 is 7.347974 psi. To calculate At then subtract 2.7 for O2 and 3.5 for N2, gives 1.147974 psi.

Viking 2 measured 2.7% N2, 1.6% Ar. If you use the Viking ratio then 2.074 psi argon. That would increase total pressure a little. Argon is a noble gas, it's safe as long as you don't use too much. But argon will drop the pitch of your voice. Harvesting from Mars atmosphere is easier if you keep the ratio N2:Ar the same as what you start with. But at least one modern measurement showed more Ar than N2. So let's keep it simple.

::Edit:: Skylab used 5 psi with 60% O2 / 40% N2. That works out to partial pressure 3.0 psi O2 / 2.0 psi N2. My recommendation is higher.

Habitat oxygen of 2.7 psi is 90% that of Earth at sea level. Boulder Colorado has 2.54 psi.
2.7 /  7.347974  = 36.74%

Last edited by RobertDyck (2021-01-10 20:05:41)

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#9 2021-01-10 18:58:48

tahanson43206
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Posts: 7,325

Re: Mount Everest Base Station Mars Habitat Simulation Site

For SpaceNut re gas in Mars suit .... Please note that there is a distinct difference between the atmosphere in the habitat (or aboard RobertDyck's ship) and the space/Mars suit.

The idea is to use pure Oxygen in the suit.  The reason for the atmosphere RobertDyck recommends (as do others) is so the personnel can don a suit and exit the habitat without pre-breathing.

In your post #7 there is a bit of text I hope you will go back and fix, because it will be confusing to readers who (we hope) will want to study this topic.

The amount of oxygen in the habitat WILL NOT be 21%.  It will be closer to 42%

The reason is that RobertDyck is recommending the habitat provide the same partial pressure of Oxygen as humans are used to on Earth, with the adjustment you can see in his post #6 ... RobertDyck recommends 2.7 PSI in the habitat, so the suit will have 3 PSI, and if there is leakage, the human occupant will be comfortable or at least accustomed to 2.7 PSI.

(th)

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#10 2021-01-10 19:39:55

SpaceNut
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From: New Hampshire
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Posts: 23,094

Re: Mount Everest Base Station Mars Habitat Simulation Site

RobertDyck wrote:

Habitat oxygen of 2.7 psi is 90% that of Earth at sea level. Boulder Colorado has 2.54 psi.
2.7 /  7.347974  = 36.74%

Is not a bad estimate for what we might try but a suit leak is from 100% oxygen not a mix.

Fire danger goes up with o2 content in a habitat so while it may be less time to dawn a space suit to go fix something its also harder to stop a fire as it flashes faster....

Nasa has been doing fire suppression experiments with some of the dragon cargo ships that have been filled with garbage when they are being disposed of....

https://www.firehouse.com/rescue/articl … ned-spaces

https://worldbuilding.stackexchange.com … t-for-fire

https://pubs.asahq.org/anesthesiology/a … Room-Fires

https://www.gdscorp.com/blog/space-moni … ed-spaces/

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#11 2021-01-10 19:43:29

RobertDyck
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From: Winnipeg, Canada
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Re: Mount Everest Base Station Mars Habitat Simulation Site

36.74% at 1/2 atmosphere pressure is not the same as 36.74% at 1 full atmosphere.

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#12 2021-01-12 07:37:56

tahanson43206
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Re: Mount Everest Base Station Mars Habitat Simulation Site

If there is a reader of this forum who is from Nepal, or who knows someone who is, please write NewMarsMember * gmail.com.

It appears (as a first impression) that one of the base camps for Mount Everest expeditions in Nepal might be an ideal location for a full scale Mars Analogue Research Station.  The location has the distinct advantage of an atmospheric pressure that is close to that recommended by RobertDyck (and others) for the habitat of a Mars facility, and for the cabins of a Large Ship to carry passengers to and from Mars.

It would be helpful if someone were to contact the Nepalese Embassy to the United States, to explore the possibility of a collaborative effort.

The Mars Society has decades of experience running Mars Analogue sites.  This would be a step up toward ever greater similarity to the Mars experience.

(th)

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#13 2021-01-13 11:04:49

tahanson43206
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Registered: 2018-04-27
Posts: 7,325

Re: Mount Everest Base Station Mars Habitat Simulation Site

Here is a follow up to the suggestion of a true Mars Analogue Research Station at one of the two base camps on Mount Everest...

Google came up with this snippet ... at this point I'm not sure if this camp is in Nepal or China. There is reported to be a base camp in each Nation.

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Everest Base Camp perched on the Khumbu Glacier at the foot of Everest is at an altitude of 5600 metres which is reached over a period of nine days with two complete rest days enroute. In terms of acclimatisation profile it is very feasible as long as you don't go too fast.

How hard is it to trek to Everest Base camp?

To move forward, I would like to see communication with Nepal about an extension of their base to include the Mars Society Research Station.

The altitude of 5,600 meters (estimated) is close to the altitude that RobertDyck recommends for consideration for an atmospheric pressure to be used at Mars for human habitat, and in the Large Ship for transport to and from Mars.

As a reminder for someone reading this post for the first time, RobertDyck recommends the pressure of the habitat to be half that of Earth sea level, so that human residents can exit the habitat, using a suit that supplies 3 psi of Oxygen, without prebreathing.

A test environment similar to the Mount Everest base camp would be helpful to confirm that RobertDyck's recommendation will work for all humans, and not just astronaut candidates or military test pilots.

(th)

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#14 2021-01-13 18:23:20

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 23,094

Re: Mount Everest Base Station Mars Habitat Simulation Site

The pre-breathing for some may be less but may still need to be a precaution for those which are not as fit as we are still in a mixed gas atmospher when not in the suit.
I agree that simulating a mars environment at high altitude simular to the other analog stations would still be of a benefit to learn just how far we can push technology and life support for man in harsh conditions.
So how would we wrap up a proposal for such a simulation and funding estimates for doing so.
What could be the funding avenues to make it less of a burden to Mars society to venture into going for it.
Would be simulate a mars journey and stay on a long cycle simular to mars with earth return to how we might process them back to civilization after being gone for so long.

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#15 2021-01-13 19:26:47

tahanson43206
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Registered: 2018-04-27
Posts: 7,325

Re: Mount Everest Base Station Mars Habitat Simulation Site

For SpaceNut re #14

Thank you for thinking about the Mount Everest Research Station idea ...

You've asked helpful questions!   Does anyone among the Registered Membership have a suggestion to move this along?

***
Regarding the atmosphere in the research facility ... It seems to me we would fly personnel in by helicopter, wearing their Mars suits, which would be the real thing.  There would be ** NO ** acclimatization! The assumption is that the atmosphere outside the habitat is NOT breathable.  The habitat  would be provided with extra oxygen to provide the 2.7 psi partial pressure recommended by RobertDyck.

If a particular guest/researcher is not comfortable at 2.7 psi, the partial pressure can be increased to 3, which would be sea level equivalent.

Hopefully we will learn that a broad swath of human guests can handle the 2.7 psi partial pressure inside the habitat.

To exit the habitat, the guests/researchers would don "real" Mars suits, and enjoy 3.0 psi pure Oxygen for the duration of their outside excursion. 

As far as funding goes ... I would hope the government of Nepal would be interested in promoting this project as a way to increase "tourism" to their country.  This would be a facility unlikely to be duplicated except by the Chinese who have their own Mount Everest base station at about the same altitude.

(th)

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#16 2021-01-13 20:47:07

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 23,094

Re: Mount Everest Base Station Mars Habitat Simulation Site

Such a structure would have an air lock, solar and other alternatives that would be locally created not imported to better simulate a mars deployment.
The shelter could be co-shared by the hikers and a means to gain funding from a local source so long as they use the air lock and compensate food and other such consumed sources while they are there. It could also be used as a hospital to hikers, communications center and so much more as a hiker support location.

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