New Mars Forums

Calliban

Member

From: Northern England, UK

Registered: 2019-08-18

Posts: 3,433

Re: Living inside Mountains / Caves on Mars?

That is a novel idea.  Urea can be manufactured from ammonia and CO2.

2NH3 + CO2 = H2N-CO-NH2 + H2O

The reaction is endothermic, but needs high pressure to take place at a decent rate.  Presumably we will be making ammonia on Mars and CO2 is everywhere.  If oxygen is produced for human breathing, then waste hydrogen can be converted first to ammonia and then to urea.

Another option for building materials on Mars is natural basalt rock, which is sawn into useful shapes.  If we are building underground, we will presumably be quarrying this out anyway.  Using diamond wire saws, we could machine stone into any shape we want.  We could also carve it using milling machines and lathes.
https://www.timbertools.com/Dario-Diamo … anite.html

Whilst industrial diamonds are expensive, the mass of cutting tools is small compared to the amount of stone they can process.  So it should be economically favourable to ship them from Earth to Mars.

Last edited by Calliban (2024-01-02 16:11:03)

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"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

RobertDyck

Moderator

From: Winnipeg, Canada

Registered: 2002-08-20

Posts: 7,811

Website

Re: Living inside Mountains / Caves on Mars?

Many years ago, I posted how to make ammonium nitrate fertilizer. That's white granules, just normal nitrogen fertilizer. Was used on farms for decades, used to be used on lawns. It's made from nitrogen, water, electricity, and some equipment you can build from stuff you can get from a hardware store. After the Oklahoma bombing, government required a license to buy it, so I don't post that any more. Let's just say you can make it. And yes, one step is to make ammonia.

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 28,884

Re: Living inside Mountains / Caves on Mars?

I agree since searches for this would be part of a topic watch consideration.

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,267

Re: Living inside Mountains / Caves on Mars?

One disadvantage of being inside a 'Cave' is it can be like a difficult outpost, stress due to broken day night rhythms or the South Pole where psychological issues are well documented, a draw back is you are increasing stress due to lack immobility, monotony, a new harsh physical environment, lack of intimate contact, sexual deprivation, lack of human interaction, missing the input from new visual stimulation, new sounds and the general isolation.

Mental health, physical symptoms and biomarkers of stress during prolonged exposure to Antarctica's extreme environment
https://www.sciencedirect.com/science/a … 652100062X

“You sound so down” – how AI technology developed in Antarctica can help diagnose depression
https://semmelweis.hu/english/2023/03/y … epression/

A lack of sunlight may cause winter-onset SAD (Seasonal Affective Disorder)

Effect of sunlight exposure on cognitive function among depressed and non-depressed participants: a REGARDS cross-sectional study
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2728098/

Perhaps Robot Doctors can give Assessment of Mental Health in Expeditionary crew, AI software artificial people who give services in Mars, Titan, Europa etc

another topic

Good Health in Transit to and From Mars
https://newmars.com/forums/viewtopic.php?id=9672

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 17,190

Re: Living inside Mountains / Caves on Mars?

For Mars_B4_Moon .... re #79

Thank you for this important contribution to the topic ....

While #79 comes across to me as showing the downside risks of life in extreme environments, it appears that some organizations have learned how to achieve success.  I'm thinking in particular of submarines which are mobile "caves" without sunlight, where personnel spend months at a time.  The military seems to have found ways to make such a life tolerable, or perhaps even attractive for carefully selected persons.

A possible technique that might be worth considering, is to generate a bath of visible light that is a near match to our familiar Sun's radiation. 

Please keep an watch for any articles that may exist, reporting on experiments with simulated sun light to improve morale in situations where natural sunlight is not available.

This forum contains at least one article about successful adaptation to life without sunlight in polar regions.

(th)

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 28,884

Re: Living inside Mountains / Caves on Mars?

How To Build An Underground Bunker You Could Live In

14 slides

Mars_B4_Moon

Member

Registered: 2006-03-23

Posts: 9,267

Re: Living inside Mountains / Caves on Mars?

Troglofauna, Troglophiles, Troglobites, Animal echolocation or animals with bio sonar, Trogloxenes live sporadically in an underground habitat and unable to establish a subterranean population.  Typical adaptations found in cavefish are reduced eyes and pigmentation, cave animals   include turbellarians, gastropods, decapods, fishes, or salamanders. Stygofauna feed on plankton, bacteria, and plants found in streams

Cave Lifeforms

https://www.youtube.com/watch?v=KjPGKZp4JwM

CAVES 2011 mission accomplished: cave crew astronauts return to Earth
https://www.youtube.com/watch?v=8T8-Csf4ThM

ESA astronauts Tim Peake and Thomas Pesquet, Randolph Bresnik from NASA, Norishige Kanai from Japan and Sergey Ryzhikov from Russia went down to partly unexplored caves in Sardinia on 17 September 2011. They lived and worked in the dark and humid underground environment for six days on ESA's CAVES 'mission'.

The cave-a-naut in the extreme environment training of the European Space Agency's Cooperative Adventure for Valuing and Exercising human behavior and performance Skills (CAVES), in Sardina, Italy

a surge in NYC crimes

NYC subway violence surge came after police patrols plummeted to levels not seen since de Blasio administration
https://uk.news.yahoo.com/nyc-subway-vi … 44018.html

FBI raids Bronx homes of Mayor Eric Adams top aide Winnie Greco
https://news.yahoo.com/fbi-raids-home-e … 11950.html
— the third federal investigation linked to NYC mayor

Cebu City, a highly urbanized city, the capital of the Cebu Province and a population of 964,169 people main domestic shipping port and is home to about 80% of the country's domestic shipping, Cebu City is the prime trading center of the southern Philippines.

67.5-km subway system proposed for Cebu
https://www.sunstar.com.ph/cebu/675-km- … d-for-cebu

Thai cave rescue victims now - from professional football careers to tragedy

https://www.mirror.co.uk/tv/tv-news/tha … w-32195337

Last edited by Mars_B4_Moon (2024-03-02 13:33:28)

Calliban

Member

From: Northern England, UK

Registered: 2019-08-18

Posts: 3,433

Re: Living inside Mountains / Caves on Mars?

Erebor wallpaper.
https://wallpapersafari.com/erebor-wallpaper/

Some images of the two underground cities that feature in The Hobbit.  Whilst this is complete fantasy, I wonder if we could build underground cities like this on Mars?  I especially like the Elvish great hall, images 22 and 42, with its Gaudiesk tree-like supporting columns.

We would probably build this under a dome, rather than actually carve it out of a mountain.  The dome itself would be a cast iron or cast basalt geodesic.  The structure would be covered with sand bags and then a thick layer of regolith, to counteract internal air pressure.  The inside surface of the dome would then be plastered, to provide a smooth, impermeable finish.  The internal structure could then be made from cut stone and adobe bricks.

https://mcdn.wallpapersafari.com/medium … BTmvyl.jpg
https://mcdn.wallpapersafari.com/medium … Q296DK.jpg

By tapering outward the compacted regolith covering the dome, the compressive stress in the regolith can be kept constant, allowing it to support its own weight and the weight of the sand bags.

The cast iron dome only needs to support its own weight.  The compressive strength of grey cast iron is 570 - 1290MPa.  Its density is 7500kg/m3.
https://www.makeitfrom.com/material-pro … Cast-Iron/

Running these numbers under Martian gravity gives a maximum possible radius for a cast iron dome of 17,902m.  This indicates that we could build domes of almost arbitrary size on the surface of Mars, provided that they remain compressive rather than tensile structures.  A 1km diameter dome would have 261,800,000m3 of habitable volume.  If this was decked, with 5m between decks, total floor space would be 52.36km2.  That is enough for a sizable city.  Maybe using cast basalt or shaped stone building blocks, we could fashion the sort of spacioys stone halls like tbe images shown above.

Building volumetric cities of this size starts to present problems for waste heat disposal.  This is where it helps to be located on a planet with substantial ice reserves.  The ice filled craters of Mars could function as ice covered cooling ponds, with liquid water pumped through the city to remove heat.  The resulting lake coukd serve three functions simultaneously.  It will remove heat from the city, keeping it cool.  Algae in the lake will generate oxygen, which will serve the respiratory needs of the city.  Finally, any fish introduced to the lake couod provide a food source.

Last edited by Calliban (2024-03-06 10:35:26)

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"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."