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Comment Re: meh (Score 1) 398

Military meals are designed with attention to the morale factor. Even the modern MRE is designed to help the soldier feel human in unfavorable surroundings. Apollo 10 was the first to officially test real bread. Gemini Astronauts smuggled aboard a kosher corned beef sandwich but it was stale and thus had too many crumbs which went airborne. By Apollo 10 it was discovered that nitrogen-flushed bread would stay fresh for 10 days. I'll have to try that.

Comment Re:Cool, but how does that help anything? (Score 1) 469

Hydrogen does not have to be shipped as a liquid or gas (more to the point, it wouldn't persist as a liquid without a significant cooling system). By mass, water is 13% hydrogen, hydrazine is 14% hydrogen, polyethylene is 17% hydrogen, lithium borohydride is 18% hydrogen, ammonia is 22% hydrogen, and methane is 34% hydrogen. Most of those compounds (and others) are useful to have on a ship regardless. And any sort of effective radiation shielding is going to have to be hydrogen rich no matter what; there's nothing that moderates down neutrons to easy-to-capture energies anywhere near as well as hydrogen.

Comment Re:(HAHAHA) (Score 1) 469

The fun part of it is that the hydrogen enters and leaves the rocket in exactly the same form; it's simply there to function as a working gas for the lithium fluoride.

I'm actually somewhat of a fan of metalized propellants, although that one is certainly extreme. ;) While there's no getting around fluorine's toxicity so I can't really get onboard with that particular propulsion system, I can picture lithium being managed - yes, lithium is dangerous, but so are chemicals like LOX (really, pretty much all oxidizers are extreme fire hazards, if not outright explosion hazards). Aluminum doesn't provide as much of an isp boost as lithium, but it provides a small one, plus a major density boost (and is cheap, too), and is nice and stable. I'm actually working on some experiments for a somewhat hybrid-esque design which involves aluminum structural elements designed to burn away and contribute to the exhaust stream.

Comment Re: meh (Score 1) 398

but what are the chances of finding a good vintage of scotch to go with all of this breaded goodness they are going to be having up there?

Alcohol is definitely going to space. Ballantine's zero-gravity glass is made in cooperation with something called the Open Space Agency, which also has a design for an automated Dobsonian telescope. Ardbeg is going to space. And a vacuum still is an old science-fiction trope.

Comment Re:Inscrutable behaviour (Score 2) 398

He's not "asking" anyone to do anything. It's a simple reality that if there was a mission to Mars coming up shortly and you passed a signup sheet around, and at the top of it was written in large letters "YOU WILL ALMOST CERTAINLY DIE AT SOME POINT DURING THIS TRIP", you'd still get thousands of signatures from people who are utterly thrilled at getting the chance and couldn't give a rat's arse about the risk.

Comment Re: meh (Score 1) 398

I knew there was a reason back in school that my binders all had pictures of sci-fi landscapes on them... it all comes full circle. Mars needs a breading program for colonists to survive... breading requires a binder... binders have pictures of Mars to encourage people to go and support the breading program!

Comment Re:1Million People (Score 2) 469

Is that not exactly what the Mars rovers were supposed to be investigating?

No, the rovers have not been gem prospecting. But the data that they've recovered would be useful for doing so. There's a lot of heavy hydrothermal veining near curiosity for example (primarily gypsum, but it's a good start!). What I wouldn't give to be there with a rover with good range...

Comment Re:Everybody should be prepared to die. (Score 4, Funny) 398

Out of several tens of billions of humans, only a fraction have not yet died, and of those who died, only a small percent of disputed cases indicate recovery.

On the contrary, I have never died before and rumors that I would do so are spread by fact-checkers of the liberal press and corrupt global warming scientists.

Comment Some Artistic License (Score 1) 398

I like the part in the SpaceX video where the rocket lands, and the door opens on magnificent desolation. This is artistic license. Obviously the material for a habitat would precede the arrival of people.

But yes, a first-try planetary colony won't necessarily work. Getting there is dangerous, and once you're there being able to continue to provide the population with air, water, food, shelter, and energy is going to have significant risks of lethal failures.

Comment Re:Cool, but how does that help anything? (Score 1) 469

I've read some papers on the subject, and it really depends on what sort of mineral you're talking about. Mars lacks or is deficient in, as you note, a lot of the processes on Earth that concentrate ores, making certain types of ores deficient. However, there are some types of ore deposits that it's expected to be rich in. A good example is bolide deposits, like the Sudbury deposit on Earth. There a large impactor created a basin which is rich in nickel, copper, and precious metals. It's not that the precious metals came from the impactor - it's that by liquefying a large chunk of the crust, it allows it to separate out into layers. Mars is struck more often by large bolides and the resulting basins are more slowly eroded, so such deposits are predicted to be notably richer on mars.

A problem with mining on Mars however is... well, mining. Overburden problems are likely to be even worse on Mars than on Earth, and I'm sure you've seen what lengths people go through to get rid of overburden. Doing that with equipment light enough to ship to Mars and keep operating? Anything but an easy task. Now, surely there's some deposits in some places that, with good prospecting effort, are low overburden and easy to mine. But then you hit the other problem which is... not everything is found in the same place, and many things distinctly aren't. And furthermore, once you build in a particular place, you're pretty much locked in there. So how do you get everything from point A to point B? Aircraft can work on Mars, but their payload capacities are terrible compared to their size, and you have to make them very fragile. Over a few hundred kilometers, your best bet is probably "mountain roads", aka you plow aside the rocks and dirt as best you can, and accept that you're going to get low throughput/high maintenance hauling over such bad roads. Over longer distances? Honestly, your best bet (in the foreseeable future) is rockets, as expensive as they are. In the long term you can talk durable cross-planet roads, high speed rail, railguns, etc. But those sorts of things aren't practical in the near term - they represent too much embodied mass, power, and/or and labour.

It's not an easy challenge

Site selection is going to be critical. The goal in the near future shouldn't be 100% independence, because that's not realistic. It should be, "what's the highest percentage of this import mass that we can eliminate?" Pick those low-hanging, high-demand fruits first.

Comment Re:1Million People (Score 1) 469

I'd think that, considering the risks, a single failure in power and all the frozen embryos will die.

A single failure in power that prevents you from keeping even a small cryopump operating, and you have much bigger problems than keeping (replaceable) embryos alive.

There is no "need" to ever send a human male. Whenever you want a local source of sperm, you can send any number of male embryos. But again, from a "maximizing reproduction rate" perspective, there is no need to send men. It's far lower mass / higher capacity to send embryos, by many orders of magnitude. And provides the corresponding orders of magnitude increased genetic diversity, rather than having everyone be siblings.

In practice, of course, travel to Mars will be an equal opportunity endeavour.

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