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Comment by baq | Hacker News Reader

This either works and will be a sight to behold or it blows up, which most definitely will be a sight to behold. In any case much to look forward to (though I’m firmly in the ’hope it works’ camp ;))

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I think some people are having wrong expectations heading in to this. If it explodes 30 seconds after leaving the launch pad it's still a huge success. Anything beyond exploding on the launch site is a success. They have a bunch more vehicles lined up behind this one as failure is highly expected, almost to the point of intention.

I'll be legitimately happy if it doesn't explode on the launch pad and at least gets any debris into the ocean instead of on land. This is just the beginning.

You are right, and expecting the first launch of a rocket platform to be anything but a bomb is a little unrealistic.

But wouldn’t it be amazing if it did make max Q, then coast, then ORBIT on the first try? It’s never happened before. But imagining the possibility gives my imagination a little bit of awe.

Starship would be the first system to run purely on our optimism! ;p

It won't go into orbit, just achieve orbital velocity. Going into orbit would require it going over land that they don't want to go over on the initial flight out of a abundance of caution.

The best thing about Starship test is that Elon will (hopefully) shut up about Twitter and focus on the important things instead of garbage.

Twitter files show that there's a MASSIVE disinformation and censorship industry in the US government. It looks like they use shady NGO's to push government sponsored disinformation and to censor civilians:

https://stanfordreview.org/stanfords-dark-hand-in-twitter-ce...

https://nypost.com/2023/03/24/malinformation-censors-excuse-...

https://www.wsj.com/articles/white-house-covid-censorship-ma...

That's only garbage if you believe democracy and liberty are garbage.

do you suppose that is the real reason Elon bought Twitter? To gain insight into that?

it's a bit fun to imagine that is the case. It is reminiscent of the "buy the whole farm" scam discussed in the film "Django Unchained". In which a huge outlandish performance is made with the stated intent to buy one seemingly desirable (in the eyes of the seller) item, but buyer's the real item of interest is disguised as just something that comes as part of the sale.

He's stated multiple times he bought it because of freedom of speech.

Whether or not he suspected NGOs were involved in the censorship on the governments behalf is uncertain, but the goal of a global communication medium that embraced freedom of speech were his main stated goals.

> He's stated multiple times he bought it because of freedom of speech.

Can we trust such a statement at face value? Should we?

That's a personal question that I can't answer for you.

I do, but I assume you don't. That's fine, carry on.

It sounds like you never saw Django. The stated goal of the heros was to buy a slave from his owner to use for brutal boxing matches, but what they really wanted to buy was the freedom of Django's wife. The purchase of the boxing slave was a ruse because there was no way the slaver would have even met with the heros if they just asked to buy the wife on her own.

My original comment was just to imagine if Elon Musk was running the same scam as in the movie when he bought Twitter. I'm not saying he did the scam, just that it would be fun if he did.

By way of support for my silly imagination: there was a bit of theatrics with the purchase and the law suit. And it's not impossible to imagine that he may have lied about the freedom of speech reason.

Yeah, that's why he has a Ukrainian "Crisis" category in his algorithm alongside misinformation, antivaxxers, criminals and porn. Amazing freedom of information, except when it is inconvenient for his alt-right friends like Trump, or himself personally.

I'm not quite aware about the govenment overreach, I'll check it later, but so far Shitter has been a dumpster fire of misinformation and spam, and Musk is keeping it that way.

> do you suppose that is the real reason Elon bought Twitter? To gain insight into that?

Or to gain control over it, therefore gaining political power as well.

This is how the US interfere in others countries' affairs through layers of NGOs, foundations, offering sabbaticals, fellowships, etc. Good to see that they can apply same techniques to their own population.

As person from "other-country" I'm all for USA so called "interference" in any form and size. Because alternative is an occupation by shitholes like China, Russia and so on. USA so called "interference" usually brings progress and civilization, while quite real interference of anti-americans brings conservatism, corruption, slavery and general degradation. This works like a clockwork, all across the globe.

Sorry I'm out of the loop/don't really understand what this is. Why would it blow up?

Starship is a massive two stage rocket/ship. Most powerful rocket in history. This is the first attempt at launching the full stack. To reach orbit, a rocket needs to be highly optimised, with little room for error. If errors occur, it could explode. Errors are most likely to happen the first time you try something.

I am aware it's not strictly aiming to reach orbit

In rocketry, the failure of any one part often results in total system collapse. This rocket has far more such parts than most. And it is a very big system. Any collapse will be spectacular. But if all goes well, that too will be a sight to see. Rocketry is about explosions: either you direct the explosion downwards as thrust or it overtakes you and goes omnidirectional. Either way, an explosion will happen.

Why would you expect your code to compile and run correctly on the first try? Same energy.

They can test / simulate as much as they want on the ground but the first full launch is bound to reveal issues.

Best case those issues just stop it from reaching the desired level of performance, more realistically they mean it goes boom at some point.

It's a rocket so there is always a non-zero risk of explosion. This one is also a new, not-yet-launched rocket, making it extra non-zero chance of explosion.

A rocket is basically a controlled explosion, and when you stop controlling it, explosion is likely.

Ah yes, just like fossil-fueled cars, but on a different scale :)

No. This is external combusion of cryogenic fuels at low pressures. There is no crossover beyond the fact that both involve rapid oxidation.

A gas engine reaches about 1200 psi, a diesel reaches about 2500 psi. Raptor’s combustion chamber sits at 4500 psi.

Which is completely nuts, even for a rocket engine. The F1 powering the saturn V only ran at 1000 psi.

On the other hand, ANFO, a common low pressure explosive, has a detonation pressure of ~100,000 psi

Its and apples and oranges comparison of combustion chambers. For purposes of combustion, the relavant pressure is the exaust of the rocket engine where combusion is complete. The burning gas within an ic engine is, at the point of combusion, at a very higher pressure. The ic equivalent of a rocket combusion chamber would be the blast wave starting at the spark, which then moves through the fuel. This difference become more important when discussing the new tech of pulse detonation rocket engines.

What is a fossil-engine if not a engine that does a bunch of small, controlled explosions very quickly? Sounds like they're identical to me ;)

This type of rocket doesnt use explosions. It burns fuel steadily. A car detonates fuel in packets. It is a different type of combustion.

I'm not aware of a single type of orbital rocket reaching orbit successfully on first attempt. Not all of them blew up, but many did.

Now I'm inspired to try to fill out this list...

Pegasus (company's first try overall), Antares, all of the Minotaurs, Atlas 3 and 5 might count as new... Epsilon, H-2 (new?), Vega, Ariane 1, 3 & 4... And the Ariane 1 is both totally new on a systems level and an institution's first attempt at building one. Long March 5, 6 & 7.

Of the investor-backed launch startups, I think it's either no company got it first try... or Orbital Sciences counts as making it first try with Pegasus. Not sure if they count as an investor backed startup.

SLS? It not only made orbit but also got it's payload around the moon. While it used many previously proven technologies (and it even previously flown engines), those were either modified or combined in previously untried ways, enough that I'd call it a new vehicle for the purposes of a flight test.

Speaking of previously proven technologies... the Space Shuttle made it to orbit on it's first launch attempt as well... with crew.

By that definition there are lots of rockets who flew successfully at first. Falcon 9 for example.

I think it is no company has reached orbit on first attempt. But they have been successful on later rockets. This includes SpaceX which was blowing up rockets phase with Falcon 1 but were successful with Falcon 9.

Zenit-3SL, Angara, Saturn family.

Falcon 9? SLS? STS?

Falcon 9 did.

Juno did just fine.

You do want to blow up (not deliberately though) this thing once though. If no prototype ever blows up before you start going into production, you never know some pieces of information you’d gave gotten from monitoring the failure process.

They really don't want it to blow up on the launch pad. They've put a lot of work into the ground service equipment, and depending on how bad the damage is, blowing up on the pad could set them back months. It also isn't clear if they will have completely finished all the protections on the launch equipment (cladding, deluge, etc) before this test flight, so blowing up on the pad this time around might actually be worse than if it happened in some future test instead.

Once it is well-clear of the pad – blowing up is a lot less bad. But still, ideally they want it to make at as far through the flight plan as possible. If it blows up early in the flight, there's a lot of stuff that happens later they won't even get the chance to test this time around. Sure, they'll get the chance to test it next time around – but that'll be another delay in an already delayed project.

They've blown up SO many Starship prototypes now, I can't keep track. It has to be like more than 6, especially if you include MK1, etc.

(This isn’t supposed to be a dig at SpaceX… just a factual statement. I find this risk-tolerant approach to be inspiring, actually.)

Always curious what sort of monitoring is used here, pressure valves, temperature, could we assume there's ultra-high-FPS cameras at every useful vantage point? Would there be any vantage point you could put a camera(or other sensor) that wouldn't get destroyed in a catastrophic unplanned disassembly?

The simplest sensor is the eyeball - "oh shit it exploded, it wasn't supposed to do that" tells you that something somewhere was calculated incorrectly or wasn't planned for.

And knowing you have an issue is half the battle.

Probably not many high FPS cameras, but a large number of the tiles, especially in the most interesting areas probably have lots of temperature and pressure sensors.

Similarly probably one regular camera in each tank and similar pressure and temperature sensing. With the engines, IIRC these are refined Raptors which don't have the "christmas tree" of instrumentation, so probably just pressure and temperature in all the key areas.

It is both unlikely to either launch or explode. Much more likely is a boring launch abort due to some technical issues, and another try in a few weeks. The opposite of a "sight to behold".

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