Red Fang

There is a fart joke in there, I'm sure.

In the current market, Big Dumb Boosters would never work, however new expendable launchers tend to keep being more and more cost effective with each generation, which is more or less in line with your 2nd paragraph. Wether reusable launchers will ever get to a point of displacing expendables or opening new markets by significantly lowering launch prices, remains to be seen in the upcoming decades.

Trying to approach this from another angle. I'd go for as many reusable/permanent items in lunar mission architecture, in order to turn it into a pork project that is difficult to cancel after the first successful flight. STS flew for thirty years before it got dumped, ISS is probably going to satay in LEO for 30 years... Apollo got caned early, and its specialized and expendable nature made it easier. Reusables/permanent structures make governments commit to a long-term project.

Any welder will confirm that not drying stick electrodes before welding is a bad idea, especially electrodes with cellulose coating. Hydrogen from electrode coating or rust buildup on the filler wire will easily penetrate deep into the weld and potentially parent metal at welding temperatures making the weld brittle. Not super important on some things, but very important on pressure vessels, or other items that may fail due to a poor weld and do damage to people and property.

I've totally read into your previous post something you haven't said. Sorry 'bout that. Yeah, a 100km sounding rocket or similar system might have been on the table at some point, maybe before procurement of FROG-7. Too much guesswork on my part. I'll shut up now.

Wow. I thought that the project was dead. That movie is really gonna kick off another wave of tinfoilery around here. lajoswinkler, I really doubt that there was a rocketry program as advanced the Redstone. The idea was probably discussed at the Central comity, maybe there was even a preliminary or feasibility study done. ...maybe.

Yeap. Science and engineering/machining are much easier in metric. Basically anything that requires precision or work on various scales, such as archaeology (plotting points on a skeleton while excavating a grave, with mm precision, on a site that is tens or hundreds of meters across, kilometers away from referent points on national grid, by using an EDM with an integrated GPS. Work scales: 1:10000:1000000:1000000000), ship building, ballistics...

and I think this personal observation might be relevant.* I make a lot of different things, but I mostly build medieval armour, which involves sheet metalwork, blacksmithing (making tools and some fittings) and some sewing and leather work. I find that using inches is slightly easier when you have to eyeball things, draw patterns cut straps, make buckles, fit things to people etc. Same applies to general blacksmithing and rough woodwork. To go to the extreme, If you use ruler/tape/string for measurement and eyeball Mk1 for precision imperial or similar system kicks ass. If you need calipers do do your measurements and your precision is in the sub mm range, you are better off using metric system (ie. in machining). Older systems, such as Imperial were developed to be very practical in certain applications, and units were specialized and scaled properly. Changing scales ended up being... unsystematic. Ie 12" to foot, 3 feet to yard, 2 yards to fathom, god-knows-how-many-whats to a mile. BTW, which mile? Than you add on top of that units for surface, volume, weight, etc all of which had similar differences, and similar types of specialization. Go to medieval times, and you'll see a terrible mess of physical units being based not only on physical world, but also on social climate: trade, taxes, labor, available measuring tools and very different calculating devices. Then there is the metric system, which is not particularly good on any scale, but is good enough on most scales, and is much more convenient for large-number-crunching. *I lived in a metric country all my life, and I mostly think in metric. I've had to learn and get the feel for imperial units 15 years ago, as most armouring books and forums available at the time were heavily using imperial units.

Probably thousands of tonnes + tens per colonist. To get a semi-self sufficient colony. You need to establish large/medium scale production of air, water (has to be dug up/piped up and purified), construction materials, steel, glass, plastics, food, copper, lubricants, industrial chemicals, machined products... You may need to ship in compost for a while as well. That list is just big enough so you could sustain basic consumables production and construction of buildings. If almost anything breaks down, you need to bring spare parts. Good luck setting up a ball bearing factory on Mars, or anything close to mass producing electronic components, or even making space suits. Setting up anything resembling a decent industrial capacity that can be self sustained for decades? Thousands of people... Almost anything you would need to set up industry on Mars is either Hi-tech, heavy or both. On an SF note... Even in Red Mars trilogy, which is optimistic at best, Mars stays dependent on technology shipped from Earth for a century. That is in a world where Arabs decide to get rid of Bedouins and other desert folk by moving them to Mars. With a good enough machining you can start rocketpunking your way by building some instruments (pressure gauges, valves, tachometers), electric motors etc... But you also need to reproduce industrial capacity for making all sorts of materials on Mars. IDK how much of that can be done with local chemistry. You'll be short on nitrogen and hydrogen for sure.

That would't surprise me at all. And I have nothing against speculation.

I'd try to explore a different angle on the whole export thing... To export anything from anywhere, in a broader sense, the property does not need to change physical location, only property rights have to be switched to an external entity. That way any permanent Martian society will at first be able to sell goods on Mars that can be competitive to goods shipped from Earth. I'd guess food and water (fuel, oxygen to cut down on amount of gear needed to recycle those?) would be first, then recycled/virgin metal and after that locally produced items of increasing complexity (structural elements, tools, pressure vessels, habs, rovers, electric motors...), including IP. Eventually, when (if) the martian population gets high enough (millions) Mars will be able to have a full range of technologies that are produced on Earth, and start physically exporting manufactured goods - ie. spaceships made in LMO. I'd expect this development to take centuries, at least. So, in this view, most of financial transactions would be happening on Earth, without money leaving it, while Mars-bound missions would be buying as much of the needed supplies and equipment at lower, local, Martian prices, therefore depressing costs of going to Mars and spending time there. How you start permanently populating Mars and how you go around economics of that, beats me.

That goes without saying. IMO SpaceX is trying to figure out a way to make the biggest, cheapest, long lasting, reliable, reusable system that can be made with minimal development in short amount of time, while probably leveraging NASA and private sector for mission specific and most of ground hardware. If they get one or two of those things wrong, they won't be going to Mars any time soon, and may go bust as a company. There fore concept of the BFR/MCT must be perfect, and then again all the steps in actual development, production and use have to be practically without fault for the system to work in a financially reasonable manner. I think they won't announce anything until they are 100% sure that they have nailed down rocket reusebility and I'd expect them to start actually designing the system after that. God knows how are they going to find money and justification for setting up anything more than a couple of semi-permanent research stations on Mars, but I wouldn't be surprised if they start a huge marketing/lobying campaign when they get confident that MCT/BFR can be made.

Rumor from L2 leaks implies SpaceX is contemplating even larger diameter core for BFR/MCT - 12m or 15m IIRC. We'll have to wait and see what they come up with at hte MCT/BFR announcement.

SomeGuy123 - More or less, yes. That is the idea. Though, i don't think masks could work very well. You would run into issues of sealing it properly against your face. What happens to eyes and eardrums if you manage to get a good seal? A vizor with a soft "helmet" and an adapter collar could be made very compact, probably less bulky than a gas mask. suicidejunkie - I don't know enough about rapid decompression to weigh in on utility of corset-like garments, but I know that any permanently rigid clothing is a poodle to wear, especially if you have to work against it. Anything that restricts your movement around the waist and/or restricts your breathing gets annoying to wear really fast. Nuke - Yes, we are mostly on the same page here. Let's say Newman manages to develop the BioSuit for a 2-year mars mission. That thing will have to endure thousands of hours of EVA in a dusty abrasive environment, so it will have to be though as @#$ck. Sacrificing some durability so you could wear in situations when combat is imminent (for hours, days or months?) in generally much less hostile environment, should not be that difficult. If it can be made reasonably comfortable, it could be worn for prolonged times. The question remains: how comfortable can it be made in the time-frame we reach conditions int the OP?

Super Guppy Airbus Beluga You can find decent encyclopedic info on most almost any aircraft on Wikipedia.