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Comment Re:1Million People (Score 1) 351

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.

Comment Re:Cool, but how does that help anything? (Score 1) 351

Shame about the atmospheric pressure and temperature... I mean, if you're a deep sea fish who likes it HOT, sure. No oxygen, either.

Why do people automatically think of planets as only existing at their surface? Yes, the environment at Venus's surface is hell. But in the cloudtops (specifically the middle cloud layer), it's the closest place in the solar system to Earth outside of Earth. Earthlike gravity, temperature, pressure, sunlight levels, and a radiation shielding equivalent to having several meters of water overhead. Yes, there is some (sparse) sulfuric acid mist, like a bad smog/vog, but then again, skin contact with Martian dust will also burn you (due to its oxidizing salts it's been described as similar to handling lye), and probably a lot faster. You can't breathe either of them, but the water won't boil out of your skin on Venus. It might well be possible (although inadvisable) to be outside in Venus with nothing more than a full face mask; contact dermatitis at those sort of H2SO4 levels will happen eventually, but not quickly. You could actually feel an alien breeze on your skin. In any case, no pressure suit is needed.

Not to mention that normal Earth air is a lifting gas on Venus. Or that H2SO4 is more of a resource than a hindrance (there's no shortage of plastics that tolerate it well, it's easy to adsorb, and it's easy to thermally decompose into water, oxygen, and SO2, as well as being one of the most important industrial acids; most of the other major industrial acids are also available straight from the atmosphere, in lesser quantities)

Access to the surface is more difficult than on Mars, but not impossible. Surface probes thusfar have used what humans would need to use to survive: the simple combination of insulation and thermal inertia. Probes have survived for over 2 hours in that manner, and it's possible to engineer to even greater survival times. These were in the lowlands as well, where the air is hotter and thicker than in the highlands. Soft suits would not be viable; as the environment most resembles deep sea diving, you need hard suits. Hard suits were actually prototyped by NASA for use with Apollo, and worked quite well (they're less restrictive to movement than soft suits); however they went with soft suits because they were lighter. One neat thing about operation near Venus's surface is that flight is very easy. Any manned suit at the surface would almost certainly be paired with a bellows balloon, which is an metallic accordion-like adjustable-lift system (which has already been prototyped and tested in Venus surface conditions)

All of that said, there's not really any good reason to put people on the surface, as you can teleoperate dredges for mining the surface (operated from the cloud deck) without any meaningful delay.

Comment Re:1Million People (Score 4, Interesting) 351

Meh, limited trade with Earth is certainly in the cards; the question of "how limited" depends on a lot of factors, but particularly their return launch costs. Even simple "Martian rock", sold as collectables or decorative stone, in small quantities could fetch tens of thousands of dollars per kilogram. Collectables markets and luxury goods markets ("Oh, the foyer in your palace is granite from Tuscany? How quaint - my foyer is from Mars") are very real things. But one order of magnitude difference in return prices equates to multiple orders of magnitude difference in the size of the market. Likewise, what exactly is available will also affect the value. A brittle sandstone for example isn't going to get the same market for the same price as big chunks of agate. We don't know what all will be found on Mars, but the presence of hydrothermal systems is encouraging; they're associated with quartz, calcite, chalcedony (agate, onyx, etc), zeolites, opal, etc. The jewelry market would be excellent to be able to break into, in terms of the scale versus what they pay per kilogram.

Comment Re:1Million People (Score 1) 351

Honestly, if you wanted to maximize population expansion rate and you were hand-selecting the crew, you'd send 100% female and cryopreserved female embryos. You'd choose women with small stature to maximize how many you can send / keep alive with a give payload mass, and ideally from families/cultures that tend to have large numbers of children starting at a young age.

In practice, of course, there are other factors beyond maximizing reproduction. Particularly if the people going are paying customers rather than people being selected by some external organization.

Comment Re:1Million People (Score 1) 351

Large numbers of manual laborers won't be required due to the large amount of advanced machinery that'll be involved

This trope is unfortunately not reality. Do we have large numbers of advanced machinery doing all of our work for us here on Earth where it's far easier to build and test them and deliver them to consumers in bulk? We only use these billion dollar robots so heavily in space exploration because we don't have people there. These general-purpose, teleoperated robots have extremely low throughput - and would have improved-but-still-low throughput even if operated locally by the absurdly-expensive local labour (expensive because their consumables are so expensive). We only put up with the tiny throughput from general-purpose robots because it's so long between launches; there's no lives hanging in the balance. And if you want higher throughput, specialist robots (as are used extensively in industry on Earth), sure, you can make and deliver those too - each one at great expense, and you need one for each task, working within tightly controlled parameters.

If you have people locally, you're not going to spend billions engineering and delivering robots for them, you're going to use them as your labour. Is ISS teeming with robots doing all of their work for them? No, the astronauts are glorified construction workers and lab techs. When you have hands in space, they're your best option - regardless of whether it would have been cheaper not to send humans at all.

Comment Re:Cool, but how does that help anything? (Score 2) 351

Despite how Elon phrased it, "water" isn't abundant on Mars. Rock-hard, gritty, perchlorate-contaminated, hexavalent chromium-contaminated clay-brine permafrost ? Yes. "Water"? No.

Mining isn't an easy thing even here on Earth - a maintenance-prone task that runs through lots of consumables - let alone on Mars where you have to choose between horrible throughput for remote operation, or local operation with astronomical local labour costs. A number of Mars in-situ proposals have outright done away with the water side of the equation, opting to harvest CO2 from the atmosphere locally (splitting to CO and O2 in a SOFC, like MOXIE on Mars 2020), but shipping in the hydrogen to avoid the need for mining. Most of the mass of fuels like methane is the carbon, not the hydrogen.

Comment Re:Let's Get One Thing Fixed... (Score 1) 351

That is not the best strategy. It is better to push forward, take risks, and fail fast. You learn more from your failures than from your successes.

Indeed. But part of the problem is that SpaceX wants to simultaneously be taken seriously as a reliable delivery service, and push the bounds for rapid, radical cost reduction. Even rockets blowing up on the test stand or failing during experimental landings comes across as bad press for them - even if they expect to have low odds of success. I've seen way too many comments and articles along the lines of "OMG, SpaceX crashed a landing, how can you think about sending up astronauts with a company that unreliable?", when the concept of "fail until you get it right" was always the plan with those landings.

If I were to start a rocket company it'd be in two parts. The first would be something like "Crazy Karen's Discount Rocket Emporium", and would go for a total Kerbal vibe, down to crudely spraypainted "This Way Up" notes on the side of stages, duct tape holding things in place on test stands, any interviews given in totally unprofessional clothing, etc. The sort of company that you'd be more surprised when things work than when they fail. The other would be your standard stuffy boring professional institution and would have a partnership with the kerbal-esque company, making clear that they acquire "promising but immature" technology from the other side, then invest their engineering resources on turning it into a refined and reliable experience for their launch service customers. All of the risky research efforts would be done by the first side.

It's effectively the same thing, but it'd make the delineation that all rocketry companies strive for explicit. You move fastest by taking risks rather than trying to avoid all failures, but you try to insulate the risk-taking side from the actual experience you offer paying consumers as much as you realistically can.

Comment Re:Wow (Score 1) 187

That's not what people were complaining about in the video. What people were complaining about was that they were landing right next to an exposed, filled propellant stage. You don't land a skyscraper-sized fireball-on-a-stick right next to a half billion dollar tank of fuel. That aspect was clearly stylized.

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