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Musk revises Mars ambitions

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Re: Musk revises Mars ambitions

#141

Post by cryptoz »

semi-extrinsic wrote: post #121
Nokinside wrote: post #75

Earlier quoted context omitted.

It's the colonizing Mars part Getting into Mars is solvable technological problem. Colonizing Mars is more economical and sociological problem than technological problem. Everyday living in high-tech place where everything is safety critical (like in a nuclear submarine or ISS) is extremely expensive. Productivity would have to be beyond everything that has ever existed for that becoming possibility. If Elon Musk can…

> Interplanetary space travel is going nowhere fast because there is no profit motive. This is so very true. We can do it for Science, and for fun, but not much else.

There's enormous profit in space. Jeff Bezos is hell-bent on moving all of Earth's manufacturing off-world. That's what Blue Origin is - a business built to create a world where mining and manufacturing are done in space, so that all Earth can be more peaceful and full of life without so many pollutants.

For SpaceX, there are people who will spend $500k or $200k on a ticket to go to Mars. If SpaceX can get us there for less than that, there's profit there too. There are enough people for moving there alone to be a profitable venture.

Many billionaires on Earth are now spending their fortunes investing in ways to make profits in space. Don't bet against them.

Re: Musk revises Mars ambitions

#142

Post by pacificmint »

r00fus wrote: post #62

I'm absolutely ecstatic that Musk is talking about the Moon. Mars is great, but Luna is near & here, and honestly, it's a strategic location (not just militarily) as the it's at the top of Earth's gravity well with a minimal well of it's own - great basecamp for interplanetary missions. If we can't occupy the Moon, why should we shoot for colonizing Mars?

There is a school of thought that building a sustainable base on the moon is actually harder than Mars.

Some of the reasons:

* No atmosphere, no source for Oxygen and Carbon * 28 day night/day cycle, hard to keep your base power over the 14 day night * Unclear if water can be found * Lower gravity

Potentially this means that way more resources would have to be brought in from the outside than on Mars.

(If this is really the case remains to be seen. But the idea that the Moon is closer, therefor it's easier has to be at least challenged)

Re: Musk revises Mars ambitions

#143

Post by fjsolwmv »

dsr_ wrote: post #134
aaron-lebo wrote: post #113

Earlier quoted context omitted.

Those won't be going away when we send humans to Mars. If that stuff is really a problem, start a colony in Antarctica. It'd be much easier to achieve livable conditions there than Mars, and your life support won't be tens of millions of miles away.

This. If you can't support a colony in Antarctica, or in the middle of the ocean, or on Emi Kousi in the Sahara, you can't do well on Mars. Run those as a test. Antarctica: breathable air, much warmer than Mars, more insolation, low light-speed lag, water. Mid-ocean: much much warmer than Mars, high pressure, low light-speed lag, lots of water. No breathable atmosphere but some oxygen can be extracted. Emi Koussi: hu…

We do have colonies in Antartica and in the open ocean (surface).

But people don't want to live there for a long time. They won't want to live on Mars for a long time either.

Re: Musk revises Mars ambitions

#144

Post by freehunter »

jawbone3 wrote: post #63
varjag wrote: post #49

Earlier quoted context omitted.

There are no true proofs outside of realm of math at all. SpaceX odds for going to Mars are, however, better than anyone else's.

Hey, that’s a big unsourced claim to make about an organisation that has no experience of manned spaceflight.

Usually when people ask for a source for someone'e statement it's a good thing, but in this case... you're really asking for a source here? Really? I mean... really?

Re: Musk revises Mars ambitions

#145

Post by cryptoz »

branchan wrote: post #125
varjag wrote: post #49

Earlier quoted context omitted.

There are no true proofs outside of realm of math at all. SpaceX odds for going to Mars are, however, better than anyone else's.

You mean besides all the agencies that have already gone to Mars?

No humans have been to Mars. SpaceX is planning on sending millions of people to live in multiple cities on Mars. This is different.

Re: Musk revises Mars ambitions

#146

Post by pacificmint »

mkempe wrote: post #80
r00fus wrote: post #62

I'm absolutely ecstatic that Musk is talking about the Moon. Mars is great, but Luna is near & here, and honestly, it's a strategic location (not just militarily) as the it's at the top of Earth's gravity well with a minimal well of it's own - great basecamp for interplanetary missions. If we can't occupy the Moon, why should we shoot for colonizing Mars?

Another interesting aspect of a moon base -- would it be easier and/or cheaper to produce propellants there instead of sending four rockets up to fuel each Mars-bound ship?

On Mars you can use the Sabatier reaction to make Methane, and you can make Oxygen from Water or from CO2.

What would you use on the Moon to make the Methane?

Re: Musk revises Mars ambitions

#147

Post by ajnin »

r00fus wrote: post #62

I'm absolutely ecstatic that Musk is talking about the Moon. Mars is great, but Luna is near & here, and honestly, it's a strategic location (not just militarily) as the it's at the top of Earth's gravity well with a minimal well of it's own - great basecamp for interplanetary missions. If we can't occupy the Moon, why should we shoot for colonizing Mars?

He didn't seem overly enthusiastic about a Moon base, he mentioned it almost in passing, as if saying "I guess a Moon base is now a possibility, if you fancy it then I suppose we can sell you some rockets for it".

I'm not very confident about ESA's ambitions either, they don't have a very good track record of achieving ambitious projects such as this one.

Re: Musk revises Mars ambitions

#148

Post by Robotbeat »

kogepathic wrote: post #138
Robotbeat wrote: post #57

Earlier quoted context omitted.

Mars is way closer. Mars has a more terrestrially-similar gravity level. Mars has way more solar power. Ceres is basically vacuum, can't aerobrake. And its gravity well is so small you also can't take advantage of the Oberth effect. Mars' atmosphere shields you from the vast majority of solar radiation (so no risk of death from acute radiation poisoning), from all micrometeorites, and even a significant amount of gal…

> Mars can be terraformed. Two questions: 1) How exactly does this work, when the mean surface temperature on Mars is below freezing? [0] I don't know a lot of plants that can grow very well in below freezing temperatures with a ton of CO2. Evergreen trees come to mind, but you won't find too many of them above the arctic circle. 2) If we cannot even properly manage the atmosphere on our own planet, why do you think…

It will likely take centuries to terraform Mars. We ARE, um, Cythereaforming Earth currently (i.e. making more like the planet Venus). And we're doing it for political reasons (fossil fuel interests).

Mars is a barren desert almost a vacuum. But no one lives there, so political opposition is less of a problem in principle. Besides, I think we'll solve the Earth's problems, too. Hopefully doesn't require extreme geoengineering like Mars does, but that's possible.

The idea is you start a self-sustaining civilization on Mars /first/ that has sufficient industry to do terraforming on its own. It will have a strong cultural and political interest in doing so. The hard part is getting a self-sustaining civilization (a city of at least a million people).

Terraforming Mars would involve pumping super greenhouse gases into the atmosphere, warming the surface by reflecting sunlight from massive (but extremely thin) mirrors in orbit, modifying the surface albedo by placing dark colored dust on the poles, and perhaps more directly by continuous sequence of fusion pulses (think inertial confinement fusion) over the poles as Musk has previously suggested. This all would cause the regolith to outgas and increase the atmosphere's pressure which should lead to more warming. Might need to beef up its atmosphere further with external source of volatiles, like icy asteroids or comets. The impact would also liberate a lot of heat itself.

Re: Musk revises Mars ambitions

#149

Post by darkmighty »

Nokinside wrote: post #75
benjaminl wrote: post #22

I don't understand why people are so quick to dismiss SpaceX's ambitions as unrealistic. They were the first to achieve re-usability of the first stage of an orbital class rocket, the first to prove out supersonic retro-propulsion and the first private company to re-fly a spacecraft (the Dragon Capsule). Given that, it seems like they should be given the benefit of the doubt when they say they are going to do somethi…

It's the colonizing Mars part Getting into Mars is solvable technological problem. Colonizing Mars is more economical and sociological problem than technological problem. Everyday living in high-tech place where everything is safety critical (like in a nuclear submarine or ISS) is extremely expensive. Productivity would have to be beyond everything that has ever existed for that becoming possibility. If Elon Musk can…

First of all, I believe that [the dream of] just making a colony on Mars, per se, is obviously pointless, and actually wasteful. Per se, a small research station would be much better, and could be productive from a global utilitarian perspective.

However, things change when speaking of an economically self-sustaining base; and eventually a base theoretically capable of full-self sustenance (not dying in case there was a transport disruption or Earth itself suffered a disaster). This simplifies the funding discussion to start up costs and r.o.i.

In that case, humanitarian-utilitarian arguments such as expanding the Human civilization to other planets (Musk's call for making life multiplanetary), backing up life, etc. also start making a little more sense (if the colony isn't self-sustaining all of those points are moot).

Is that feasible? Certainly not today, but perhaps in 50 years?

I mean, a civilization doesn't actually need that much to sustain itself. The basic needs are (a) energy, and (b) materials. Obviously Mars receives Solar power (about 45% as much as Earth per m^2), and it has materials (all basic industrial elements are present in the crust).

The question is, can we start an industry on Mars that is efficient enough today such that the cost of producing and maintain infrastructure (solar panels, mining equipment) is lower than the output from the products? If your solar panel gives 10MJ during it's lifetime, you need to use at most 10MJ (used in mining and manufacturing) to produce it. That's an engineering analysis, and I'm it will be eventually feasible. It also improves with economies of scale.

Re: Musk revises Mars ambitions

#150

Post by pacificmint »

kogepathic wrote: post #138
Robotbeat wrote: post #57

Earlier quoted context omitted.

Mars is way closer. Mars has a more terrestrially-similar gravity level. Mars has way more solar power. Ceres is basically vacuum, can't aerobrake. And its gravity well is so small you also can't take advantage of the Oberth effect. Mars' atmosphere shields you from the vast majority of solar radiation (so no risk of death from acute radiation poisoning), from all micrometeorites, and even a significant amount of gal…

> Mars can be terraformed. Two questions: 1) How exactly does this work, when the mean surface temperature on Mars is below freezing? [0] I don't know a lot of plants that can grow very well in below freezing temperatures with a ton of CO2. Evergreen trees come to mind, but you won't find too many of them above the arctic circle. 2) If we cannot even properly manage the atmosphere on our own planet, why do you think…

The idea would be to thicken the atmosphere of Mars, ideally with CO2, so that the greenhouse effect will warm up the temperature.

Obviously this is engineering on an extreme scale and long timeframes.

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