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A newly discovered moon tunnel

washingtonpost.com

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Re: A newly discovered moon tunnel

#161

Post by simulate »

drdrey wrote: post #141
spdustin wrote: post #60

Earlier quoted context omitted.

The moon's core isn't made of the swirling molten iron dynamo like Earth's is. No swirling molten iron, no magnetic field. No magnetic field, nothing deflects the solar wind that then, literally, blows away any fledgling atmosphere. It's believed that Mars' atmosphere was considerably more dense than it is today, but along the way, its core cooled, and it lost its protective magnetic shield, allowing the solar wind t…

Even with a magnetic field, would the moon's gravity be sufficient to retain an atmosphere?

Yes, it is possible that with a magnetic field the moon's gravity would be sufficient to retain an atmosphere. Titan has an atmosphere denser than earth's atmosphere despite having a lower gravity than the moon. There are a few hypotheses why and one of them is that, although Titan has no magnetic field of its own, it orbits inside Saturn's magnetosphere. https://astronomy.stackexchange.com/questions/8345/how-does-...

Re: A newly discovered moon tunnel

#162

Post by alex_duf »

jlebrech wrote: post #154
interfixus wrote: post #133

> It might even contain ice or water As a boy in the early seventies, reading Tintin: Destination Moon , I was always put off by the episode with the underground cave full of slippery ice. That was clearly an outdated view of lunar conditions, which somewhat dented my suspense of disbelief. Maybe I needn't have worried.

the rocket looked silly too, but it turns out that's how we'll do it. elon musk may we bald with a goatee too by then.

Would he be Elon Dupont or Elon Dupond?

Re: A newly discovered moon tunnel

#163

Post by hutzlibu »

larkeith wrote: post #140
hutzlibu wrote: post #116

Earlier quoted context omitted.

With lenses you could also burn the soil to produce gases that add up to he atmosphere ... but we want breathable atmosphere. With lot's of oxygen and very little co2. And that is a bit harder ... So you also couldn't just vaporize the ice, you need to split it up. Solar heat could be sufficient, but the water will then be missed everywhere else on mars where life wants to grow. And Mars is dry. So I would first use…

I wonder if it would be a reasonable colonization process to establish a non-breathable atmosphere, allowing postprocessing facilities to later separate oxygen from airborne water vapour. The notable benefits from such an approach would be the ability to easily deliver asteroid-based water deposits (aim it at Mars, let reentry do the rest), as well as the significant simplification of ground based colonization techno…

True, I think I would agree, there are many immediate benefits.

But it has to be carefully considered, as it might hinder a longterm plan for a nice, breathable atmosphere.

But once we reach mars, we are probably busy first, with primitiv things such as life support ...

Re: A newly discovered moon tunnel

#164

Post by jlebrech »

alex_duf wrote: post #162
jlebrech wrote: post #154

Earlier quoted context omitted.

the rocket looked silly too, but it turns out that's how we'll do it. elon musk may we bald with a goatee too by then.

Would he be Elon Dupont or Elon Dupond?

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

Re: A newly discovered moon tunnel

#165

Post by hyperpallium »

harperlee wrote: post #146
hyperpallium wrote: post #120

Earlier quoted context omitted.

But the moon is one-face, so tidal stress should be constant.

What about the sun's? If the force is strong enough to make earth orbit, and moon-to-sun distance oscillates, plus seasonal behaviour, there must be quite some straining tides...

oh yeah, that makes sense. It's a tiny fraction of the moon-sun distance, but it would have some efrect. Is it a "tidal" force, though?

Re: A newly discovered moon tunnel

#166

Post by newsbinator »

wongarsu wrote: post #109
yeukhon wrote: post #98

Earlier quoted context omitted.

Am I incorrect without an active lava core, the magnetic field is basically non-existient? Then Moon tunnel is probably not good enough for humans to remain healthy.

Rock is pretty good at shielding from electromagnetic radiation. It obviously depends on how deep you are, but any shielding beats no shielding.

Also water serves as very good shielding. Anybody living in caves in the moon would naturally need an ample water supply (a "closet" full of water containers), which could double as an emergency radiation shelter.

Re: A newly discovered moon tunnel

#167

Post by LeifCarrotson »

kobeya wrote: post #128
waegawegawe wrote: post #115

Earlier quoted context omitted.

Think about how large of a lens you're talking about. Even if it were one hundred meters across and was able to collect 100% of the sun's energy passing through it, the amount of energy produced would be utterly insignificant compared to the problem we're discussing. And how would you get a one hundred meter lens to mars orbit? Even after that, you have to consider that we want an oxygen atmosphere, not one made of w…

That's about ~250x the JWST. Given that we're talking about a society that has developed far enough to be sending people to Mars and terraforming the landscape, I don't think that 8 doublings would be an unreasonable multiplier of current capability. Still a flagship, many-decade mission though.

The James Webb mirror is a rigid, astonishingly precise focusing element. A solar energy mirror could instead be merely approximately parabolic, made of a foil instead of cryogenic, made of metalized kapton instead of gold-plated beryllium, would forego focusing elements, and so on.

However, the thought of a telescope-quality mirror 250x the size of the JWST is pretty amazing :)

Re: A newly discovered moon tunnel

#168

Post by andai »

extrapickles wrote: post #130
icanhackit wrote: post #76

Earlier quoted context omitted.

NASA proposes building artificial magnetic field to restore Mars’ atmosphere: https://www.universetoday.com/134052/nasa-proposes-magnetic-...

Interesting, it only needs a 1-2 Tesla magnetic field. MRI machines go up to 3T, which means this isn't too outlandish with known technology. The main issue is that they probably want a Mars sized field at 1-2T.

Does that mean it needs a bigger coil?

Re: A newly discovered moon tunnel

#169

Post by andai »

hyperpallium wrote: post #165
harperlee wrote: post #146

Earlier quoted context omitted.

What about the sun's? If the force is strong enough to make earth orbit, and moon-to-sun distance oscillates, plus seasonal behaviour, there must be quite some straining tides...

oh yeah, that makes sense. It's a tiny fraction of the moon-sun distance, but it would have some efrect. Is it a "tidal" force, though?

The sun also creates the tides.

Re: A newly discovered moon tunnel

#170

Post by [deleted] »

LeifCarrotson wrote: post #72
kirillkh wrote: post #68

Earlier quoted context omitted.

Then we have no hope of ever engineering Mars to have enough air for us to breath?

A Martian atmosphere (not sure about a lunar atmosphere) would be lost on a timescale of tens of millions of years. That's very quick in cosmological timescales, but slow enough that any human effort to create or replenish it could be very successful.

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