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Starship Update [video]

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Re: Starship Update [video]

#261
post #240

Earlier quoted context omitted.

> Why do we need to fly 3 months to some inhospitable planet that is in worse condition than Earth would be (even after nuclear wars and global warming) to make progress? In the late 1500s, why set sail across an ocean for weeks that no-one has ever successfully crossed (that we know of). Someone would want to do it, and then want to do it regularly, and regularly means commercializing it, which means reduced cost an…

> is richer after the "discovery" of America and Australia, for example. And then there was ethnic cleansing of native population.

True, and even if everyone were a moral saint the pox would been devastating. But this was not a garden eden, but a very brutal tribal world with frequent ethnic cleansing and enslavements. Hundred thousands of native auxiliaries marched with Cortez to get rid of their Aztec overlords.

Anyway, this won't be an issue for Mars.

Re: Starship Update [video]

#263

Earlier quoted context omitted.

Yes, if someone is struggling to survive, that will limit their ability to become a world-changing entrepreneur. That said, the average westerner is not struggling to survive, and the average westerner does not end up founding 3 world changing companies and amassing a wealth of $200 billion. Not even the average birthright 1%er achieves that.

Its not even that complex. If there was an identical Elon that came one year after Elon, he wouldn't be able to have what Elon has. It's all luck of the draw all the way down.

How about why no idential Elon came the year before Elon? It's not like the idea of powered landing was unheard of, and tech ingredients were there for arguably decades.

Re: Starship Update [video]

#264
post #13

Earlier quoted context omitted.

Why do we need to fly 3 months to some inhospitable planet that is in worse condition than Earth would be (even after nuclear wars and global warming) to make progress? I suppose there's an idea we could apply everything done on Mars to Earth, but like... seriously, what we just took all the prep for mars and just put it in the middle of the Empty Quarter, the Saraha, Antarctica? People barely want to live in the arc…

The basic idea is to not have all your eggs in one basket. We are one asteroid strike away from losing all human life on earth. Having 2 habited planets spreads the risk. Obviously having those planets in different solar systems would be even better, but we don’t have the technology for that, yet.

From a species POV sure, from an individual POV living on Mars would be miserable..

Re: Starship Update [video]

#265

nothing better than letting the earth be destroyed so that the idea of multi-planetary life has relevance. better future for humanity is have a better earth

What a load of nonsense. Going to space lets us have a better Earth! Even at a simple level, we use satellites to monitor sea level, methane emissions (even identifying leaky pipelines from orbit!), atmospheric levels of CO2, NO2, SO2, etc., vegetation cover, ice cover, and on and on.

https://en.wikipedia.org/wiki/Earth_observation_satellite#En...

Re: Starship Update [video]

#266
post #253

Who would have thought space travel was much "easier" than self driving cars.

As hard and complex as spacecraft are, they seem like tractable engineering problems.

The sheer raw complexity of the human built environment and traffic is very daunting for computing. Calculating orbits and rocket burns seems trivial by comparison.

Re: Starship Update [video]

#267
post #124

Earlier quoted context omitted.

I thought 100k HP was either too incredible or a typo. Then I looked it up: “You def don’t want electric pumps on a rocket engine! Raptor turbopumps alone need 100,000 horsepower per engine. That’s not a typo.” —Elon Musk x 32 engines. Amazing! For comparison, this is an internal combustion engine with 100k HP: https://www.zmescience.com/science/biggest-most-poweful-engi...

That is interesting, so could you replace the biggest and most powerful internal combustion engine in the world that weighs 2,300 tons by [whatever powers] turbopumps from a raptor engine and get the same power output? Where is the catch? Less fuel efficient? Less torque? Edit: What I meant to ask was: Can one use "whatever is powering the turbopumps and delivering the 100k HP" to power say a ship propeller, instead…

You could in theory do that. The downsides are that a turbopump needs comparatively perfect fuel, requires liquid oxygen instead of air, and would be inefficient in non-rocket applications (the ‘waste’ has other uses like cooling/protecting the rocket nozzle in some rockets).

Think of it as an engineering tradeoff where you get to pick 2 things to optimize for: weight, efficiency and size. A turbopump (and preburner) optimizes for weight/size. A ships engine picks efficiency twice, making it massive and heavy.

Re: Starship Update [video]

#268
post #192
post #183

Earlier quoted context omitted.

>This engine makes everything else possible. I have seen lot of tweets ( from highly intelligent people and engineers ) suggesting Starship is not possible. Raptor 2 is not possible. But now it seems it really is coming. It is easy to fault him for robotaxi and FSD, which a lot of people do. But sometimes he really does the impossible.

The chamber is still melting. Hopefully they can figure that one out.

Source? Several raptors have been fired for long duration and even multiple times. If the chambers would melt that should not be possible.

Of course RUDs of engines happened but they were the exception and not the norm.

Re: Starship Update [video]

#269
post #124

Earlier quoted context omitted.

I thought 100k HP was either too incredible or a typo. Then I looked it up: “You def don’t want electric pumps on a rocket engine! Raptor turbopumps alone need 100,000 horsepower per engine. That’s not a typo.” —Elon Musk x 32 engines. Amazing! For comparison, this is an internal combustion engine with 100k HP: https://www.zmescience.com/science/biggest-most-poweful-engi...

That is interesting, so could you replace the biggest and most powerful internal combustion engine in the world that weighs 2,300 tons by [whatever powers] turbopumps from a raptor engine and get the same power output? Where is the catch? Less fuel efficient? Less torque? Edit: What I meant to ask was: Can one use "whatever is powering the turbopumps and delivering the 100k HP" to power say a ship propeller, instead…

Used everywhere, more complex and has a more limited operating parameters though. In the maritime industry it has generally been military or high speed ferries using them. Essentially, if your ship can get away with a larger more mechanically simple engine it is more economical because as long as they stay on the surface you are not paying the fuel price of also lifting the engine.

Commercial jets use the same mechanics with their turbofan engines. That is why they are growing huge, we're just encasing the propeller inside the cowling, with some other nice side-effects.

https://en.wikipedia.org/wiki/Turboshaft

https://en.wikipedia.org/wiki/Turbofan

Re: Starship Update [video]

#270
post #192

Earlier quoted context omitted.

The chamber is still melting. Hopefully they can figure that one out.

Source? Several raptors have been fired for long duration and even multiple times. If the chambers would melt that should not be possible. Of course RUDs of engines happened but they were the exception and not the norm.

Also, the only non-intentional engine RUD that I know of is SN8, where debris from ground destroyed the engine avionics at takeoff. Any other incident?
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