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Super Heavy has splashed down in The Gulf of Mexico

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Re: Super Heavy has splashed down in The Gulf of Mexico

#491

Post by DarmokJalad1701 »

cletus wrote: post #449
Majromax wrote: post #193

Earlier quoted context omitted.

> I'm not sure one rocket can launch a geostationary satellite above the Americas and above Europe in the same mission. Easily. Moving within an orbit is a matter of fine adjustment. For example, any stationkeeping that expands the orbit slightly will cause the satellite to "fall back" over time. Geostationary satellites are the best orbit for this, since every satellite in such an orbit essentially shares it with al…

I'm not sure this is true. if it were, there wouldn't be launch windows because any correction within a given orbit would be, as you call it, "a fine adjustment" yet we clearly do have launch windows. Also if you're in a geostationary orbit to deliver one payload you have to leave that orbit to get to another geostationary orbit because there are other satellites in your way.

It is a fine positioning, which takes time. The launch windows get you to the right spot right away. Someone paying for a dedicated launch doesn't necessarily want to wait around to get their satellite operational. Someone launching for cheap on a rideshare might be willing to.

Re: Super Heavy has splashed down in The Gulf of Mexico

#492

Post by bee_rider »

dylan604 wrote: post #434
bartread wrote: post #379

Earlier quoted context omitted.

The way the booster comes down is nuts. 90km to 1km in 100 seconds, it reaches maximum velocity under gravity at a bit over 20km, then air resistance acts as a brake, and they only fire the engines to slow it down the rest of the way at 1km. Bonkers.

The thing that tickles me is that it has to slow down to reach terminal velocity rather than the normal way of thinking about objects speeding up to reach terminal velocity.

I’m probably missing something important here, but isn’t this true of most things that de-orbit into an atmosphere?

Re: Super Heavy has splashed down in The Gulf of Mexico

#493

Post by robertsdionne »

notact wrote: post #217
pixl97 wrote: post #68

What the hell, half melted starship actually did the landing flip and hit the ocean slow!!! That was amazing!

Can someone explain why reentry must be so hellish? The energy gained during the rocket burn into orbit must be bled off during reentry, and that energy is enormous. However, why must reentry occur so quickly? It seems if the descent into the atmosphere was slower, the heat shield would be able to radiate the heat energy away more effectively, thus lowering skin temperatures, and significantly reducing the engineerin…

You are not riding the atmosphere down, the atmosphere is riding you.

Re: Super Heavy has splashed down in The Gulf of Mexico

#494

Post by aeternum »

dotnet00 wrote: post #381
delichon wrote: post #81

Watching pieces of the ship melt off, but then seeing it make a relatively controlled landing, is perversely confidence building. If it can survive that kind of damage on a control surface maybe it's a quite robust craft.

Reminiscent of the booster in IFT-1 just doing spins in the air, refusing to break up even after the flight termination system was triggered. Completely unlike KSP with its wobbly rockets.

A KSP with more realistic physics would just be amazing. Unfortunately from the KSP2 vids it looks like they instead doubled-down on wobblyness.

Re: Super Heavy has splashed down in The Gulf of Mexico

#495

Post by metadat »

bearjaws wrote: post #3

The rate of descent is absolutely astonishing, 8km -> 1km in 20 seconds, then just hovers above the water. Absolutely incredible work by the SpaceX team. Living in central Florida I cannot wait for the new launch facility to come online. We're going to have lines of spectators into the space coast like we did for the shuttle. If any of you are heading to Disney World you should stop by the NASA Kennedy Visitor Comple…

In case you want to watch from the time of liftoff:

https://www.youtube.com/watch?v=lFkqZF-Ss7o&t=6250s

Re: Super Heavy has splashed down in The Gulf of Mexico

#496

Post by JackFr »

jaggederest wrote: post #389
somenameforme wrote: post #344

Earlier quoted context omitted.

The 'worst' thing about watching space launches on streams is that you simply cannot grasp how ridiculously huge these things are. Even if, like in the stream today, you see a water tower for some scale, the size discrepancies just make it so hard to intuit. Starship is 121 meters high. That's something taller than a football field, jetting off into space! I've only gotten to see a decommissioned Space Shuttle in per…

Standing next to the S-IC stage from the Saturn V at Kennedy really puts it into perspective. And the Starship full stack is larger and taller than the Saturn V!

https://upload.wikimedia.org/wikipedia/commons/5/51/Saturn_v...

Saturn V slight larger than Statue of Liberty.

I never realized that.

Re: Super Heavy has splashed down in The Gulf of Mexico

#497

Post by gpm »

bee_rider wrote: post #492
dylan604 wrote: post #434

Earlier quoted context omitted.

The thing that tickles me is that it has to slow down to reach terminal velocity rather than the normal way of thinking about objects speeding up to reach terminal velocity.

I’m probably missing something important here, but isn’t this true of most things that de-orbit into an atmosphere?

They're comparing to the average falling object not the average de-orbiting object.

Re: Super Heavy has splashed down in The Gulf of Mexico

#498

Post by zizee »

themgt wrote: post #94
pixl97 wrote: post #68

What the hell, half melted starship actually did the landing flip and hit the ocean slow!!! That was amazing!

That was seriously some of the most dramatic television I've ever watched. Video of Starship being melted/torn apart by supersonic plasma, the broadcast stream dying multiple times maybe due to ship destruction, then finally back online, peeking through the cracked camera to see the nearly destroyed grid fin STILL ACTUATING. The announcers laughing about the ship being "maybe held together by some nuts and bolts" and…

A friendly fyi just in case it wasn't a slip of the tongue: grid fins are only on the booster.

Re: Super Heavy has splashed down in The Gulf of Mexico

#499

Post by pandemic_region »

tim333 wrote: post #371
somenameforme wrote: post #344

Earlier quoted context omitted.

The 'worst' thing about watching space launches on streams is that you simply cannot grasp how ridiculously huge these things are. Even if, like in the stream today, you see a water tower for some scale, the size discrepancies just make it so hard to intuit. Starship is 121 meters high. That's something taller than a football field, jetting off into space! I've only gotten to see a decommissioned Space Shuttle in per…

I've got the black and white arty photo as my lockscreen which gives you an idea https://cdn.mos.cms.futurecdn.net/E46BxzjjUkpthVBNE6k8mn-192...

oh wow, i always imagined those breaking fins to be about tennis racket size !

Re: Super Heavy has splashed down in The Gulf of Mexico

#500

Post by aeternum »

Zigurd wrote: post #450
api wrote: post #120

Earlier quoted context omitted.

I’ve said for a while that we won’t be ready for the real space age until you can have a rusty pickup in space. What I mean by that is that we have it down well enough that the tech exceeds tolerances and can degrade gracefully. You see this in some sci-fi where there are rust bucket old ships that work.

That doesn't work IRL. Space is insanely unforgiving. While Starship has a vastly better chance than STS had of achieving rapid reusability, you really can't launch with a rocket that isn't up to spec because adding robustness adds weight. Unlike a multi-stage expendable rocket, Starship uses all its fuel to get to orbit. To go to the moon or beyond, it requires refueling by several other Starships that also just get…

The vast majority of the weight however is oxidizer which you could theoretically eliminate since the rocket is surrounded with various amounts of oxygen depending on launch trajectory.

A scramjet power first stage for example could overcome the tyranny of the rocket equation (at least on earth).

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