tater

Apparently they're gonna try again Sunday.

You don't need much fuel at all, you just need time. You can herd a small asteroid, attach an ion drive to it, heck, a solar sail might be feasible. It just might take many years to get it to L@, or wherever is deemed safe. Even a small rock loaded with rare earths would be a windfall---at "rare" rare earth prices. Flood the market, and the price plummets. So the economics seem to be a long timeframe to get it, then you might have a lot to sell, but you need to sell in small units to maximize profit (sort of like DeBeers and diamonds. Diamonds only have value because the market is controlled, they are common, and should be cheap.

I read that Niven when it came out. I think it is not impossible, the universe is a rather large place. That said, it kind of depends on how you define conditions for life. If you are open to exobiologies that might not be as likely/plausible, then pretty much anything goes. If you require liquid water, and radiation within some limits, then maybe it's considerably less likely---but again, there are many neutron stars and white dwarves out there, so you only need have some form of life on a vanishingly small % to have the answer be, "yes."

The economics of mining rare earths, etc, has got to be interesting, and I'd personally be interested in the take from an economist if there is an article out there to read. It seems like they are valuable entirely because they are rare. The cost to drag an asteroid to orbit with a huge supply might actually be small compared to terrestrial mining, at which point in order to keep the price up, they mining outfit would have to triple supply down, else they'd be doing something expensive (space mining) to collect a product that is cheap. It's an interesting balance.

Many of them are deployable. Just try deploying them.

It's a reference to The Princess Bride. Inconceivable!

Iocane powder?

The Commander flew the LEM, not the LM Pilot. Strange, but true. Maybe Dr. Rendezvous did the orbital piloting?

Until very recently I had never used anything like mechjeb. I got Gravity Turn recently, and have been messing with it to consistently test designs (a kopernicus rescale, though, not stock). Honestly, once a design is decent launches are pretty much hands-off anyway. Regardless, I think it's interesting to experiment with it (it's entirely novel to me at the moment). All that said, I think that there should be options to do everything in KSP, not only "autopilot" (which in effect is every real launch we watch), but having kerbal pilots actually able to pilot. I consider the important "piloting" to be setting up maneuver nodes, though the most fun piloting to me is propulsive landings. That is something I'd basically always want to do myself. I'm thinking of career mode wrt kernels as functional pilots, because as a "manage a space program" game, I think that having the ability to hand certain routine tasks off allows you to do different things with less tedium. Setting up an infrastructure to assemble larger ships in orbit, for example, then letting the staff at least place things nearby each other, or docked to a station so I can do final assembly would be interesting. Resupply missions (I always use life support)... I dunno, I think that it would be interesting to see, even if I'd want to do it myself most of the time.

The abs themselves need only be as big as you'd like them to be for living for that period (or just one, with perhaps the return craft and service module as counterweight), then a long cable. have them rotate about a 100m CM, keeping RPMs down. A 100m tether (floor to center point, so the cable is slightly shorter) means 1.84 rpm. If they used 2 Bigelow habs, they could have a ~43m tether from the center point, place one, then a second at the full 100m length and you could experiment with lunar and martian at the same time.

I'd think the first experiment would be to buy a couple large Bigelow habs, then spin them up to 0.38g and see how people (and animals) do long-term. That can at least establish if there are acute issues associated with some g level below 1, and above 0 (a regime for which we have zero data). If martian gravity won't cut it long term, there is no reason to bother with any of the rest of it at all.

The idea of lifetime limits hadn't occurred to me (in which case cosmic/solar radiation might make more sense... what would the mechanism be,though? Would they become tourists? (there is no "retired" due to reaching an exposure limit mechanism in game)

Yeah, there could certainly be some economies of scale with people sharing habitation. On the other hand, more people could create more wear and tear... I honesty don't know. The other issue is that a failure without recourse results in death for everyone sharing life support. A 1% chance of killing 4 people is different to consider than a 1% chance of 100 or 1000 deaths.

Solar wind is actually complex, but like cosmic radiation could be simply approximated as isotropic (it might not be worth bothering with either, frankly). Solar flares, OTOH roughly approximate to LOS from the sun, and are acutely dangerous. The player would need a mechanism to deal with them (if pointing was a solution). I'm not sure if KSP has the requisite tools to deal with such events (warn the player, or ideally have the crew deal with it (because there is no AI).

They'd either show up with the capability to produce replacement parts or they'd not have that capability for a very long time. Construction, even farming could be labor intensive. "Mining" on Mars would largely be harvesting the atmosphere, though you could drive water, etc, off regolith as well---that could use a few people. Industrial capability would need to be delivered. In the indeterminate future, we could have truly game-changing manufacturing technology as 3D printing matures. It's all the rage now, of course, but I worked with rapid prototyping guys at Sandia Labs, gosh, 20 years ago. The machines are far cheaper now, but the quality is not really much different as far as I can tell (the new laser sintering stuff is substantially different though). Then the manufacturing using isru needs to focus on making printer supplies. What size plant would you need to harvest enough carbon to meet the plastic needs of a growing colony?

I pretty much never even look at the aircraft parts.

Suggest new SRBs as "RATO" for spaceplanes, and we'll likely see 10 added to 1.1 at the last minute, because "spaceplanes."

How long is a good Mars launch window? Let's call it a month on either side of the ideal launch. A few years into the planned (OP) 1000s of colonists, they need to launch a huge spacecraft to Mars every day for 2 months. I didn't get an answer on how sustainable that was . I also don't see any estimates of how quickly they could become self-sufficient in manufacturing complex items required for survival using only indigenous materials. The MIT guys who debunked MO did a great service in pointing out the logistical hurdles, and how the number of launches quickly grows to a point where it would eat any even ridiculously optimistic budget, and indeed even eat up the entire budgets of all space programs on earth, combined, just to keep the few people there from croaking.

I'd say no sane government would do that, but then I look at "programmatic" spending, and who knows.

A better plan would be to send the minimal amount of people required to build a certain infrastructure first, only sending others when it can support them. So perhaps the first 50 people build stuff, start farming, etc. When they can support another 50, send more. When those can support 100 more, etc.

I wasn't suggesting this was the exactly the same as MO, I was saying that in their critique of MO, the MIT guys provided useful benchmarks in units of 4 people and D2 landings on the martian surface. Using their data, which seems reasonable, their logistical train for 4 people was about 4 D2 landings (2 mt useful payload each). MCT claims 100 mt to the surface (unsure if this is payload or includes the craft, let's say payload for kicks), that's 1 mt per person. Apparently improved life support from ISS extrapolates to another mt per year of parts, etc, per person. So you need 25 launches for the 1st 1000 people, and 20 every other year just to support them, plus the new 1000 people. The MO counter-arguments still apply, though we might get some economies of scale for LS... or more people might wear out LS faster than our tiny ISS experiments have shown... who knows? So it's sort of the same thing. Logistics is all that matters for an endeavor of this kind. I'm assuming the MCT is a thing, and it can launch as often as needed. I'll assume anything you like, but this isn't Sonoma, CA we're dropping the people off at, you cannot simply dump 1000 people, and then forget how many launches they need ever launch window going forward. There is zero chance they are self-sufficient from the start. What is a reasonable time window for this to be achieved? 10 years? Is that 10 years for just 1000, or for 5,000? It matters. Year 1 launch 25 MCT. (1000 people, plus supplies) Year 3 launch 45 MCT. (1000 new people, plus supplies for previous 1000) Year 5 launch 65 MCT. (1000 new people, plus supplies for previous 2000) Year 7 launch 85 MCT. (1000 new people, plus supplies for previous 3000) etc. How sustainable is this scenario?

The MIT guys slammed Mars One for their logistics, showing that each deliver of 4 people would incur an additional 4 Dragon 2 landings (from memory, it might be more). I want to say each Dragon2 was 2 tons landed. MCT claims 100 tons to the surface (wiki). That's 1 ton per person. Using the MIT figures (as I remember them), it's then 2.5 tons per person (the bulk being replacement parts). So 1000 people would require 25 launches, and they'd be living in the spacecraft, that's aside from any industrial equipment. They'd need some substantial inflatable habs, some sort of passageway inflatables, and equipment to move soil over everything for radiation shielding. They'd likely need substantial nuclear power plants landed to facilitate any mining of regolith past using it as shielding, as the mechanisms usually involve lots of heat. Seems like CO2 "mining" would be more of the equipment. I know concrete is another possibility that has been worked on.

Do not answer! Do not answer! Do not answer!

The issue with the moon as colony (I'm going to assume my definition that means people born and raised there, possibly never leaving during their lifetimes) is that it is very unclear if 1/6 g is adequate for humans. Currently we have 2 data points, 1g, and near 0g. Any assumptions made without establishing the long-term health effects (including embryology) of values below 1g are not really worth anything, they are guesses. This also applies to Mars, BTW.

This is not true over reasonable time frames, and not true at all when you look at mass/cost. Take current telecontrol of Mars rovers. Absolutely, a human could drive a rover faster right there. But mars rovers have lasted many, many years. 2 proposed Mars missions have either s short duration stay, or over a year. In either case, the possible sample selection per unit time might be higher, but the duration is vastly shorter. On top of that, the human mission is allowed what, 900 tons to Mars orbit in the 1990s, down to 450-650 now? You need to demonstrate that robots could not do as much given the same ~500 TONS delivered to Mars to do the work. The robots win right now, and 10 years from now, they'll be considerably more capable than they are right now. Samples? The manned mission must return the crew, plus samples. Robotic sample return given identical resources could life all the mass of samples, plus the mass used for crew and their life support requirements. You could send multiple rovers, as well, and collect samples from areas that vary for the same cost. Sure, the geologist can pick great rocks quickly, but he's limited to XXkm around the landing site, anyway. Given the same resources, you could pout a couple rovers in interesting, "safe" places, and land others in places you've not risk landing a crew (due to terrain). Sorry, but science as a rationale is pretty much indefensible. If we're sending people, then by all means maximize the science, but we should not pretend that people would be more effective/efficient at delivering the data we need.