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

SpaceX test flight of Starship SN-5 [video]

youtube.com

Post reply on HN
Print view View original

251–260 of 391 posts

Re: SpaceX test flight of Starship SN-5 [video]

#251

Post by extrapickles »

paranoidrobot wrote: post #81
extrapickles wrote: post #68

Earlier quoted context omitted.

Also, since its mostly made from steel, it will be fairly simple (as far as rockets go) to conduct repairs, you just need a welding rod or two. This is important for early stage bases where you don't have the equipment/materials to make carbon fiber or exotic aluminum alloy replacement parts.

Given how much difficulty they've had with welds and materials to date, is it really feasible to conduct in-situ repairs without a ton of advanced equipment?

It probably depends on what needs repairs. Repairs around the fuel tanks will be difficult as they would not readily have the equipment to purge the tanks of the fuel/oxidizer. Anything that is bulk structural is likely to be repairable to some extent.

I would not be surprised if part of the reason for building these in a tent is so they can gain experience for building/repairing these rockets with as little infrastructure as possible.

Re: SpaceX test flight of Starship SN-5 [video]

#252

Post by jcun4128 »

martythemaniak wrote: post #205

I really love the out-in-the-open development process. It doesn't cost SpaceX anything, yet they attract lots of internet media where people set up streams, discuss progress etc. The next year should be pretty exciting as they develop things further. Starship has a number of big innovations, which are: - the raptor engine. This was developed behind closed doors and is sort of finished. We won't see much of it, but it…

> 31 raptor engines

That'll be something to see haha N1

Re: SpaceX test flight of Starship SN-5 [video]

#253

Post by njarboe »

napier wrote: post #247
martythemaniak wrote: post #205

I really love the out-in-the-open development process. It doesn't cost SpaceX anything, yet they attract lots of internet media where people set up streams, discuss progress etc. The next year should be pretty exciting as they develop things further. Starship has a number of big innovations, which are: - the raptor engine. This was developed behind closed doors and is sort of finished. We won't see much of it, but it…

> any upcoming engine that can compete with it. There's the criminally underfunded SABRE engine, an a air-hydrogen mix breathing-rocket hybrid design from Reaction Engines that rated to reach speeds of Mach 25 (roughly 35,000 miles per hour). As modelled, it's more efficient than any other current or proposed chemical propulsion technology, and the proposed single-stage runway launchable system would be capable of de…

SpaceX needs $kg to orbit to be much lower for their Mars plans to be possible. It is planning on their starship and superheavy rocket combo to bring down current launch costs by a factor of around 100 in the long term. A factor of two improvement in costs is not interesting to them.

Re: SpaceX test flight of Starship SN-5 [video]

#254

Post by bconnorwhite »

ben_w wrote: post #160
jacquesm wrote: post #149

Earlier quoted context omitted.

You write that as if it is a done deal. Mars' atmosphere is roughly .5% of that of Earth and almost exclusively CO2. Temperature ranges are well out of what they are on Earth. It is hard for technology to survive there, it is impossible for people to survive there until there has been an unbelievable investment in infrastructure. If you think there will be a million people colony on Mars in your lifetime than you are…

Although I’m also not expecting 1 million people on Mars in my lifetime, I think you’re assuming SpaceX never gets close to the Musk price goals. You might be right to do that — I’m no rocket scientist — but the target price would get a million people there for $200 billion, not your $5 quadrillion. Yes, I also expect the first few thousand to be in easily damaged domes. I also expect them to bring some of The Boring…

The other factor is that Musk has nothing better to spend his money on. With Tesla + SpaceX + Boring + Neuralink he'll likely be a trillionaire by the time Mars colonization is full swing. Even if the price was $2T instead of $200B, Musk might be able to fund most of this himself.

Re: SpaceX test flight of Starship SN-5 [video]

#255

Post by bconnorwhite »

ncmncm wrote: post #158
jacquesm wrote: post #149

Earlier quoted context omitted.

You write that as if it is a done deal. Mars' atmosphere is roughly .5% of that of Earth and almost exclusively CO2. Temperature ranges are well out of what they are on Earth. It is hard for technology to survive there, it is impossible for people to survive there until there has been an unbelievable investment in infrastructure. If you think there will be a million people colony on Mars in your lifetime than you are…

To get a sense of the difficulty, imagine sending a million people to the South Pole to set up a self-sustaining colony. That would be much more than 1000 times easier than establishing such a base on Mars.

True, but I'm not sure difficulty is as relevant if the motivation is there. You can't terraform the South Pole. Mars reopens the frontier whereas the South Pole is a dead end

Re: SpaceX test flight of Starship SN-5 [video]

#256

Post by nickhalfasleep »

napier wrote: post #247
martythemaniak wrote: post #205

I really love the out-in-the-open development process. It doesn't cost SpaceX anything, yet they attract lots of internet media where people set up streams, discuss progress etc. The next year should be pretty exciting as they develop things further. Starship has a number of big innovations, which are: - the raptor engine. This was developed behind closed doors and is sort of finished. We won't see much of it, but it…

> any upcoming engine that can compete with it. There's the criminally underfunded SABRE engine, an a air-hydrogen mix breathing-rocket hybrid design from Reaction Engines that rated to reach speeds of Mach 25 (roughly 35,000 miles per hour). As modelled, it's more efficient than any other current or proposed chemical propulsion technology, and the proposed single-stage runway launchable system would be capable of de…

It's incredibly complex and has exceptional engineering challenges to make work.

That much cryogenic hydrogen and massive temperature differences is as the limit of engineering possibilities.

Re: SpaceX test flight of Starship SN-5 [video]

#257

Post by [deleted] »

throwaway0a5e wrote: post #224
shireboy wrote: post #185

Earlier quoted context omitted.

I’ve often said the same thing. South Pole and underwater cities would be easier than mars or even moon colony. As much as I want the later to happen- I think 1 million people on Mars or Moon will require something that makes them more appealing than even the worst Earth locations. That has to be something pretty drastic. Elon says motivation will be “it’d be cool”. I don’t think that is enough motivation. Still, I’d…

Africa was in Europe's back yard yet when they got the opportunity they colonized the Americas. Colonizing a formerly unexplored place where nobody has yet laid claim has a lot of appeal (and this time we (probably) don't have to kill/displace the natives to do it).

[deleted]

Re: SpaceX test flight of Starship SN-5 [video]

#258

Post by zamalek »

llboston wrote: post #43
zizee wrote: post #33

No one has seemed to have mentioned it yet, but the game changer of Starship will be full reusability of both the first and second stage of the rocket. Falcon 9's reusability of the first stage was a huge step towards making access to space a lot cheaper. If SpaceX can realize full reusability with Starship it will enable things like large scale moon bases, space hotels and mars colonization. They still have a lot of…

Another significant thing is that Starship is designed to be mass manufactured at a relatively low cost. SpaceX can crank out thousands of Starships, fly them to Mars and build a million people colony. Starship is truly a game changer!

> mass manufactured at a relatively low cost.

... which also explains Tesla, mass production of Earth-faring machines is one way to prepare for mass production of space-faring machines (and battery tech is going to be important for living in space). When you look at Musk's ventures, they really all end at Mars.

Re: SpaceX test flight of Starship SN-5 [video]

#259

Post by balfirevic »

sandworm101 wrote: post #245
martythemaniak wrote: post #205

I really love the out-in-the-open development process. It doesn't cost SpaceX anything, yet they attract lots of internet media where people set up streams, discuss progress etc. The next year should be pretty exciting as they develop things further. Starship has a number of big innovations, which are: - the raptor engine. This was developed behind closed doors and is sort of finished. We won't see much of it, but it…

>> - in-orbit refueling. Starship is big and heavy and basically can't get anywhere unless it's re-fueled in orbit. This is one of those "let's see" things that SpaceX has talked about but never actually explained. Their current rocket tech offers no hint as to how this is might happen. They aren't running internal bladders in their tanks. So the physical act of moving fuel from one tank to another is an open questio…

Some rockets have already used small acceleration prior to engine ignition to settle the propellant in zero gravity situations: https://en.wikipedia.org/wiki/Ullage_motor

Re: SpaceX test flight of Starship SN-5 [video]

#260

Post by skykooler »

sandworm101 wrote: post #245
martythemaniak wrote: post #205

I really love the out-in-the-open development process. It doesn't cost SpaceX anything, yet they attract lots of internet media where people set up streams, discuss progress etc. The next year should be pretty exciting as they develop things further. Starship has a number of big innovations, which are: - the raptor engine. This was developed behind closed doors and is sort of finished. We won't see much of it, but it…

>> - in-orbit refueling. Starship is big and heavy and basically can't get anywhere unless it's re-fueled in orbit. This is one of those "let's see" things that SpaceX has talked about but never actually explained. Their current rocket tech offers no hint as to how this is might happen. They aren't running internal bladders in their tanks. So the physical act of moving fuel from one tank to another is an open questio…

At the last presentation on Starship, Elon said they planned to do the refueling by applying a small amount of thrust during the procedure, giving a small g-force that's enough to drive the fuel from one ship to the other.
Post reply on HN