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Starship Flight 5: Launch and booster catch [video]
291–300 of 1001 posts
Re: Starship Flight 5: Launch and booster catch [video]
#292Earlier quoted context omitted.
Is that 150t of payload or total? What’s the cost in fuel alone (let’s ignore maintenance and operations costs for now)? I’m trying to get a feel for the relative scale compared to today’s commercial flight.
Methane is about 900-1500$ / ton. About 1000 tons is used for the launch in addition to 3600 tons of lox. That should be a bit cheaper than methane per ton. Ballpark, the propellant might cost around 2M$. A modern airliner on a long flight might burn around 80 tons of kerosene. It's slightly cheaper than methane. Call it 75-80K$.
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Re: Starship Flight 5: Launch and booster catch [video]
#293I went to follow this on the SpaceX YouTube channel since it is usually closer to real time.
It seems someone hijacked and played a video of the previous launch. Just as we got to launch time it cut to a fake badly dubbed speech by Elon Musk going on about Bitcoin, with a handy QR code.
This was a bit confusing but since it was 10 minutes in advance I managed to switch to another channel.
Still amazing, even if the video glitched at the key capture point.
And an hour later the Starship itself re entered to soft salty sea landing.
I don’t know how many prototype runs they need to do, I’m guessing they could stuff a shed load of Starlinks into the next one.
Re: Starship Flight 5: Launch and booster catch [video]
#294I went to follow this on the SpaceX YouTube channel since it is usually closer to real time. It seems someone hijacked and played a video of the previous launch. Just as we got to launch time it cut to a fake badly dubbed speech by Elon Musk going on about Bitcoin, with a handy QR code. This was a bit confusing but since it was 10 minutes in advance I managed to switch to another channel. Still amazing, even if the v…
Sounds like you were on a scam, fake version of the channel.
Re: Starship Flight 5: Launch and booster catch [video]
#295Can someone explain to me why this is more impressive than landing the rocket? To a layman like me, it looks very similar - the thing looks just like a rocket but without a pointy tip, and on the way down I don't understand why difference that matters. (I mean I still think it's mind blowing, because I think landing a rocket is also mind blowing)
This booster is significantly larger than anything landed on an orbital launch before. Here is a size comparison, previous largest landed orbital rocket stage is the SpaceX Falcon 9 (three of them launch together as Falcon Heavy) on the left. Starship is on the right.
https://upload.wikimedia.org/wikipedia/commons/7/7b/SuperHea...
Landing via tower catch versus on a pad is advantageous because the weight of adding retractable landing legs to such a large rocket would be significant.
Re: Starship Flight 5: Launch and booster catch [video]
#296Very inspiring, glad I woke up to watch it. Congratulations to the SpaceX team. This is what competition looks like. It’s funny how last decade SpaceX had to sue the government to get more launches.
The FAA needs more funding at this point. They're not staffed for the rate of launch requests which commercial space has grown too.
More money would make the situation worse. They need competent leadership. Everyone like to just say “add more money” because it means no actual operational change to the status quo.
Re: Starship Flight 5: Launch and booster catch [video]
#297Nothing could have prepared me for how that catch looked. I was sure the rocket was careening into the tower at the last second before it straightened out. The control algorithms must be incredible for the landing system to work within those small tolerances.
MIMO and nonlinear control theories are probably some of the hardest topics in all of engineering. SpaceX control system also has to compensate for the fuel moving inside their rockets so the control algorithms probably involve some kind of fast numerical fluid simulation. Another interesting thing SpaceX is doing is to use consumer-grade chips in triple redundancy configurations instead of using $100,000+ radiation-…
Reminds me of the early days of Google File System.
They used trios of regular consumer grade disks/servers etc as a cluster and it looked like a single node.
They had to replace a LOT of hardware but this was still cheaper than big iron industrial grades servers.
Re: Starship Flight 5: Launch and booster catch [video]
#298Can I hijack this thread for an almost completely unrelated question that I have observed in nearly every simulation of movement in space, even from sources like NASA and SpaceX which “should know better”?
And I’m mostly asking this out of scientific curiosity, not as a criticism.
Why do they always portray movement in space by showing stars moving past the view at variable rates, or even at all?
The opening screen of this video while you’re waiting for the feed to start shows stars moving that seem to be only feet away, and only a few inches in diameter. Like little orbs of light just passing outside the window.
Isn’t this highly unrealistic, for even extremely fast travel in space?
I would imagine at most you would see very slow movement of a very static field of stars. But every depiction in sci-fi, video games, and other simulations like in this video insist on making it seem like space is full of tiny 6-12” stars floating only feet away from each other.
Is there any explanation where this could actually be considered realistic that I’m not thinking of?
I’m just a lowly software engineer, so my expertise in this area is null. But from a basic understanding of stars and physics, this seems unrealistic.
Admittedly, I guess it wouldn’t be very exciting to view movement in space in a way that I’m imagining would be realistic, and maybe that’s the only explanation there is/needs to be.
But I guess I’m thinking that there would be enough people at SpaceX (for example) to scream “this is not even close to realistic!” for something like that to not make it to production, even if it is more exciting to watch.
Re: Starship Flight 5: Launch and booster catch [video]
#299At this point I am finding it hard to hate Elon Musk. For everything he does that has annoyed me (like Gloating at people being bombed in the middle east) — his business acumen has completely unlocked for people what they we thought was impossible.
You should be glorifying Shotwell, not Musk. Yes Must helped give her room to build but she's the genius and deserves the credit.
Re: Starship Flight 5: Launch and booster catch [video]
#300Earlier quoted context omitted.
I wonder what will happen when they get to 99% reliability? They clean up and rebuild the Mechazilla every once a hundred catches, on that occasion that one fails?
I suspect there's already a whole "refurbishment" process for the crane even for non-reusable launches, and once it's working darn reliably, they can just have a bunch of them ready to go, and cycle once in a while.
The next one is already mostly built and very different from this one. They move fast.