Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Elon Musk’s plan to build one Starship a week and settle Mars

arstechnica.com

Post reply on HN
Print view View original

331–340 of 351 posts

Re: Elon Musk’s plan to build one Starship a week and settle Mars

#331

Post by aguyfromnb »

grey-area wrote: post #256
aguyfromnb wrote: post #88

Earlier quoted context omitted.

> So yes it seems reasonable to me that these are groundbreaking challenges. Isn't weld strength something engineers would know/understand in advance, though? How would it come as a surprise that the welds would fail under pressure? It seems strange to me that Musk could be spending so much time working on Starship, and somehow a "badly designed, badly built, and badly checked" rocket makes it to the platform and exp…

There are additional constraints not found in most welding projects. They can’t just make the material and weld thicker/heavier as that would impact the rocket performance. So it has to be as thin and fragile as possible but no thinner. That makes it very hard to get right, and the welds have to be done to very fine tolerances on thin material, you could say it is rocket science.

>They can’t just make the material and weld thicker/heavier as that would impact the rocket performance.

I understand. But the stresses that materials and welds can withstand are not unknown variables. We're talking about a pressurized tank here. You aren't going to build a rocket (designed to carry people) that has tolerances so tight that it's touch and go whether it explodes as soon as it's pressurized.

Re: Elon Musk’s plan to build one Starship a week and settle Mars

#332

Post by aguyfromnb »

dexen wrote: post #257
aguyfromnb wrote: post #244

Earlier quoted context omitted.

> Automobiles Automobiles were developed over hundreds of years. What was the skepticism there? > Lightbulb Edison "invented" the first commercial bulb in 1879. The first electric lights were created in the early 1800s. > Printing press People were trying to find ways to print books for centuries. Copying them was laborious. Some random monk claiming hand-writing to be morally superior doesn't change that.

To counter, "first lightbulb", "first automobile", "first airplane flight", "first color photograph" etc. are always arbitrary thresholds; much ink has been spilled over who, when, and where; over what exactly makes a lightbulb or whatever else. "First rocket" was probably constructed & launched around the time of gunpowder invention, i.e., in the 9th century China. That's not quite the same as reliably getting cargo…

>To counter

I agree with you, but this isn't really a counter-argument; it bolsters my point.

The examples the OP gives of things that were coinsidered "not worth the time" were, in fact, so desired that the time between "first" and "first commercial" was sometimes spread over tens or even hundreds of years.

These were not things that skeptics wanted thrown in the dustbin, but instead a Great Man worked on to bring them to fruition. They were fine tuned over long periods by many people.

We have this weird thing where you can find a quote by some monk, or Steve Ballmer and the iPhone and we think, "No one believed!" But there is plenty of evidence (judging by time from "first" to "first commercial" ) that people saw value from day one. The iPhone was a big step, but itself was still just an iteration. That's how progress works.

Re: Elon Musk’s plan to build one Starship a week and settle Mars

#333

Post by cstross »

nopzor wrote: post #317
viklove wrote: post #315

Earlier quoted context omitted.

What are you building the starships out of that they can withstand those forces continuously over multiple years?

wouldn't 1g of force be the same as they'd be subject to sitting on earth?

Starships sitting on Earth are under compression. Starships hanging from one another's nose via a tether are presumably under tension, unless the tether is somehow anchored to the engine support structure at the base of each vehicle. So some non-trivial structural modifications would be required.

Re: Elon Musk’s plan to build one Starship a week and settle Mars

#334

Post by cstross »

carapace wrote: post #258
cstross wrote: post #181

This is a spectacular gamble, however Musk has a track record and I think Superheavy/Starship will pay off with unpredictable dividends. But the elephant in the room that Musk appears to be ignoring is the life sciences side of things. Only 12 humans have sortied outside the Van Allen belts (which protect us from the deep space radiation environment). Nobody has spent more than 18 consecutive months in space or reduc…

Then we'll merely go to the Moon. :-) (And LEO and the Lagrange points.) You raise a good point IMO in re: viability of space. In the limit it may turn out that humans can't live anywhere but on or near the surface of Earth. What is certain is that living in space will suck for many years, or likely decades. It will be like living in a mine, but there are more things that can kill you and you're much much further fro…

This is why I like to draw a distinction between space exploration and space colonization. The former is definitely within the realm of possibility, using existing technology (never mind the Superheavy/Starship system).

But Musk, with his talk of a self-sufficient city, is clearly targeting the latter, and there are a whole lot of details we haven't worked out.

Re: Elon Musk’s plan to build one Starship a week and settle Mars

#335

Post by cstross »

carapace wrote: post #259
gentleman11 wrote: post #254

Earlier quoted context omitted.

What about the sci-fi ships that rotate very quickly and use the momentum as a form of false gravity - iirc, the basic physics seems legit (I recall an Einstein thought experiment along those lines). Or: use the acceleration/deceleration to create gravity. Are they impractical to build or power?

Are you thinking of an O'Neill colony? https://en.wikipedia.org/wiki/O%27Neill_cylinder > The O'Neill cylinder (also called an O'Neill colony) is a space settlement concept proposed by American physicist Gerard K. O'Neill in his 1976 book "The High Frontier: Human Colonies in Space". O'Neill proposed the colonization of space for the 21st century, using materials extracted from the Moon and later from asteroids. > An…

O'Neill's colony design is flawed (and needs updating): in particular they had huge glassed-in window areas to admit sunlight (focussed via reflectors) for agriculture: he didn't account for differential heating-induced expansion/shrinkage.

On the other hand, he didn't have modern CAD back in the early 1970s. So in principle we can come up with something better.

The biggest problem is exposure to cosmic radiation -- L5 is way outside the Van Allen belts and high energy cosmic rays take roughly a metre of water to attenuate, or magnetic fields of 10-20 Tesla strength around the spacecraft. Which is a lot of mass (or a ridiculously strong magnetic field).

See also: https://en.wikipedia.org/wiki/Health_threat_from_cosmic_rays

Re: Elon Musk’s plan to build one Starship a week and settle Mars

#336

Post by kamaal »

cstross wrote: post #181

This is a spectacular gamble, however Musk has a track record and I think Superheavy/Starship will pay off with unpredictable dividends. But the elephant in the room that Musk appears to be ignoring is the life sciences side of things. Only 12 humans have sortied outside the Van Allen belts (which protect us from the deep space radiation environment). Nobody has spent more than 18 consecutive months in space or reduc…

Like every other discovery on earth, the first set of explorers will have to risk life and limb, make sacrifices to get there.

The one's that follow will build several stops along the way. You will be able to stop, stay for a while, and move forward towards your journey.

Also Asteroid mining is going to be a thing. So economy, space labs and all.

Re: Elon Musk’s plan to build one Starship a week and settle Mars

#337

Post by thu2111 »

kybernetikos wrote: post #306
thu2111 wrote: post #235

Earlier quoted context omitted.

I'm a huge Musk fan and would love to see us settle mars. But. Really. What's the threat model here? Mars is meant to be a backup of humanity. OK. Against what threat? We can think of many, but a self-isolating base in the Antarctic would survive nearly all of them with better conditions than a Mars base. Nuclear armageddon? Not much fallout over Antarctica and OK, you can't go outside of a while. Still better than M…

Antarctic city is good. I like underwater cities personally. A decent depth of water is very good protection against an awful lot of stuff, including almost anything Mars would be good for, and if you still love space, any technology we build to live deep in the ocean can probably be reused on Europa. It's also, to bring it back to the 'iteration' discussion way way easier to iterate building underwater cities than b…

Yeah, exactly. Problem is 'underwater base' is probably too easy to build. Within a few years you'd be asking people to actually live there and then ... well good luck motivating employees with that vision!

Re: Elon Musk’s plan to build one Starship a week and settle Mars

#338

Post by BigBubbleButt »

thesmok wrote: post #328
BigBubbleButt wrote: post #320

Earlier quoted context omitted.

An engineer was imprisoned because another engineer was spiteful. You don't consider this a dumb political decision? I consider the default judgment of "everyone goes to the gulags" to be shitty governance, and also quite stupid. My understanding is Korolev's health greatly declined because of his time while imprisoned, and had he never had to endure it he likely would have lived much longer.

I must point out that username ilyich is a transliterated name likely referring to Lenin – real name was Vladimir Ilyich Ulyanov. So ilyich seems to be a fan of USSR.

That much is obvious. It doesn't mean I don't want to hear his perspective though.

Re: Elon Musk’s plan to build one Starship a week and settle Mars

#339

Post by UnFleshedOne »

immmmmm wrote: post #175

I don’t get the point 1) we are plain in the middle of a mass extinction event, expected to get much worst in a decade or two. Wouldn’t it be good to solve that first? 2) we need a 4th industrial revolution to survive global warming as a civilization. Wouldn’t be better to fix that first? (No, electric cars won’t suffice) 3) is it really necessary to spoil astronomy/night sky to finance one’s dream? (No, vantablack w…

Re your 4th point, this is exactly why you want a working space presence -- if you move all your mining off the planet you just remove one future failure point.

Also, there are lots of people, humanity can walk and chew gum at the same time. On best of the days anyway.

Re: Elon Musk’s plan to build one Starship a week and settle Mars

#340

Post by UnFleshedOne »

nixpulvis wrote: post #182
aperrien wrote: post #178

Earlier quoted context omitted.

Instead of being fatalistic and bemoaning the problem, you'll find yourself in a better mental space if you just apply yourself to solving it. Yes, you will only start with small steps, and yes, that will be a great risk, but in the end it the only chance we have of making things work.

I do not follow your argument, and I don't appreciate your appeal to my mental state. I'm making a dramatic argument against large scale efforts to inhabit other planets, while ours is in a dire state.

Fixing climate change is a political problem first of all. A very different set of talents is needed here.

You'll have to convince or force people to change their priorities. First is probably not possible, due to the slow moving nature of the threat, second has its own drawbacks as well.

Post reply on HN