Elon Musk doing AMA at 3pm PST

[abasile]

For meteorite and radiation protection it is better to live under ground. Replace windows with displays.

That is more sensible if not attractive. I'd still like to see shielded, transparent domes, though, even if only for limited use.

Another, unrelated issue may be that with the lower gravity (roughly 1/3 that of Earth's gravity), children born and raised on Mars may not naturally possess the bone mass to tolerate Earth's gravity in the event they want to relocate to Earth. Some intervention may be needed, as I can't imagine many Martian parents would want to limit their children to only one planet.

 

[VolkerP]

I missed the AMA but enough folks on this forum to discuss the following question:

Living on Mars will be hard, terraforming it even harder. It has only 0.5% of Earth's atmospheric pressure and no magnetic field to protect from cosmic rays. Increasing atmospheric density is hard to come by since the upper layer it just boils away into space.
Is it possible to bombard mars with mostly iron/nickel meteors diverted from the asteroid belt, until it develops a magnetic field and enough gravitation to hold an earth like atmosphere?

 

[Grendal]

I missed the AMA but enough folks on this forum to discuss the following question:

Living on Mars will be hard, terraforming it even harder. It has only 0.5% of Earth's atmospheric pressure and no magnetic field to protect from cosmic rays. Increasing atmospheric density is hard to come by since the upper layer it just boils away into space.
Is it possible to bombard mars with mostly iron/nickel meteors diverted from the asteroid belt, until it develops a magnetic field and enough gravitation to hold an earth like atmosphere?

I don't think so. Dropping a lot of nickel-iron asteroids would put that material near the surface. It would need to be near the core to create a magnetic field. Long ago, I read where you could drop a lot of large ice asteroids onto the surface to assist in creating an atmosphere.

Whatever you do, Mars needs a lot of work. It will never become an Earth-like planet simply because of its lesser gravity.

 

[AudubonB]

So - how can one re-create a Van Allen-like shield without a core-sourced dynamo....err, magnetic field?

I'm thinking there may be another way to do this but might be a tad challenging on a planetary scale.

 

[ecarfan]

Another, unrelated issue may be that with the lower gravity (roughly 1/3 that of Earth's gravity), children born and raised on Mars may not naturally possess the bone mass to tolerate Earth's gravity in the event they want to relocate to Earth. Some intervention may be needed, as I can't imagine many Martian parents would want to limit their children to only one planet.

(Disclaimer: I am a neurophysiologist not a physician or developmental biologist, so take what I say with a healthy dose of skepticism)

In my inexpert opinion, humans born on Mars will remain on Mars because they will not be able to tolerate Earth gravity. Even if at some point in the future some sort of powered "exo suit" that provides artificial support to the human body is developed that still may not enable a Mars-born human to exist on earth because their heart may not be capable of supplying sufficient blood to their brain when they are upright on Earth. So if they come to Earth their activities will be extremely limited and they may be in constant discomfort.

Over the centuries the humans on Mars will change sufficiently so that they could eventually be considered a different species. They will be much taller, have longer limbs, less bone mass (not needed), less musculature, smaller hearts, and who knows what else. They will be able to interbreed with Earth humans who come to Mars but they will look very different.

 

[ecarfan]

So - how can one re-create a Van Allen-like shield without a core-sourced dynamo....err, magnetic field? I'm thinking there may be another way to do this but might be a tad challenging on a planetary scale.

I don't see how Mars could be modified by humans to have a magnetic field.

It's going to be hard enough to give Mars a breathable atmosphere. First step is to warm it up, then you have to figure out how to retain the atmosphere you are generating from the frozen water and CO2 at the poles.

 

[CarlitoDoc]

Thought Ama was a new model he was "doing"

 

[BluestarE3]

Would it be simpler instead to build a "Death Star" and place it into solar orbit? It doesn't have to be anywhere as large as Mars to support a sizeable human population, with its own internal environment, artificial gravity, hydroponic farms, and Tesla solar panels completely covering the exterior to generate electricity. It could be shielded to block harmful cosmic radiation from its inhabitants. It could be placed to orbit closer to the sun than Mars so that flights to/from this outpost will take less time and it will get more sunlight for its solar cells.

 

[AudubonB]

Ah - but I didn't write "magnetic field", did I?

I wrote "Van Allen-like shield".


There's a need to think outside the box a bit here.

 

[ecarfan]

Would it be simpler instead to build a "Death Star" and place it into solar orbit? It doesn't have to be anywhere as large as Mars to support a sizeable human population, with its own internal environment, artificial gravity, hydroponic farms, and Tesla solar panels completely covering the exterior to generate electricity

"Simpler"? No. Mind bogglingly expensive to do that, definitely. And such an artificial "planet" would have no natural respources, unlike Mars which has many.

New Ah - but I didn't write "magnetic field", did I?
I wrote "Van Allen-like shield".
There's a need to think outside the box a bit here.

I stand corrected.

However, I think humans are a long way off from having the technological capabilities to do what you are asking.

 

[jkn]

That is more sensible if not attractive. I'd still like to see shielded, transparent domes, though, even if only for limited use.

Of course they would have observation rooms on surface. Perhaps transparent cupolas, but not for living. Enterprise in original Star Trek had display instead of window. Of course display can show infrared, X-ray, radar,... images with any magnification. After that designs have devolved.

I don't see how Mars could be modified by humans to have a magnetic field.

It's going to be hard enough to give Mars a breathable atmosphere. First step is to warm it up, then you have to figure out how to retain the atmosphere you are generating from the frozen water and CO2 at the poles.

Superconducting cables around the planet would do it. Something like in this idea: StarTram - Wikipedia

Implementation would take some time...

Would it be simpler instead to build a "Death Star" and place it into solar orbit? It doesn't have to be anywhere as large as Mars to support a sizeable human population, with its own internal environment, artificial gravity, hydroponic farms, and Tesla solar panels completely covering the exterior to generate electricity. It could be shielded to block harmful cosmic radiation from its inhabitants. It could be placed to orbit closer to the sun than Mars so that flights to/from this outpost will take less time and it will get more sunlight for its solar cells.

This has to made on asteroid belt. Asteroids have more accessible resources than Mars! Ceres has plenty of water. Perhaps some others also. When ready it could be moved slowly closer to The Sun. Of course raw materials could could be sent from asteroids to Earth orbit. Mining colonies on asteroids are needed anyway. They need industry to maintain and expand. So why not build colony ships there?

 

[3Victoria]

No reason not to do both Mars and asteroid belt and any number of other projects over time