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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

#212

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Columbus very very much didn't plan to die (though he very much would have if he didn't get lucky that there was a whole new continent there). His plan was to land in India, which he thought he would reach around the time he actually reached the new continent, because he had a completely wrong idea of how large the globe actually was (he alone had this wrong idea; the actual circumference of the globe was pretty well…

We will probably perform a human mission and return samples before a robot goes and picks up the Perseverance samples. We’ve been mars-capable since Apollo. It’s a matter of will, which is a political function of cost, which is falling rapidly.

> We’ve been mars-capable since Apollo.

serious citation needed!

you cant make shit up. Apollo and saturn5 were nowhere near getting humans to mars. Not even close.

It got us to moon with bare minimum. A weekend trip vs 6 months trip.

The scale up of needed resources is mind boggling. At every step. I mean pick any step and explain how Apollo could achieve it.

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

#213
post #109
post #60

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Yes, there won't be as many customers purchasing 150-200 tons of lift, but that's the point of "rideshares". All that really matters with space launches is the cost per kg and if it's capable of lifting multiple payloads into multiple orbits, it'll have 10-15 customers per lift, not one. The current model has a kind of pez-dispenser but for chucking out multiple payloads. There are purchasers for the full lift capaci…

If you think about this, it doesn't make a lot of sense because different satellites are going to sit in very different orbits. Geosynchronous satellites are an obvious case where satellites will collect into a limited number of orbits but they vary on what point of the Earth they sit over. Also getting to geostationary orbit takes a lot more fuel so the rocket has less room for payload than, say, low EArth orbit. I'…

> I'm not sure one rocket can launch a geostationary satellite above the Americas and above Europe in the same mission.

It can. Geostationary satellites are a certain distance above the equator. If they adjust their orbit a tiny bit lower than that they start to drift east, if they adjust their orbit a tiny bit higher they start to drift west. This process is called "repositioning".

Generally there is a tradeoff between how much fuel you spend on it and how fast the repositioning is done. So you can do it quick and then your sat will have less fuel for position keeping. Or you do it "slow" and then you preserved more fuel potentially extending the lifetime of your satellite.

But these are all done with tiny bits of fuel (compared to the fuel needed to put the satellite up there in the first place) because the delta-v involved is very small.

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

#214
post #113

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The vision is that the cost per unit of mass to orbit will come down massively with Starship, once it's launching like the Falcon. That will open up hitherto unimaginable missions and markets. And customers. It's all about the the cost!

It's not only about cost per kg but also maximum payload mass. If you can build bigger satellites then you don't need to optimize for weight as hard and can use cheaper components/standardize. Which means both launch cost and sat costs will come down.

Or entirely new capabilities get developed. Look how long it took for the F9 Heavy to get any business because fitting payloads really only got planned and developed after it demonstrated its abilities.

With the Starship, there will be single payloads of 100t or more - Elon is even talking about 200t in future versions. That is a total game changer. A station like the ISS could be set up much quicker. You could start designing real spaceships with e.g. ion drives. And a 100t payload might even cost less than currently a single F9 flight.

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

#215
post #195
post #161

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> Landing and then what you plan a flag and die? Pretty much, why do you think columbus set off? And he didn't even know if he'd actually find anything. I don't understand your attitude and people like you, human beings have been explorers forever, and seem to value exploring even over survival potentially. I'd say it's pretty obviously evolutionarily coded into us. Maybe not you, but into many people.

I think it is the indelible human nature, to go the furthest we can because it's there. At first I didn't agree with going to Mars, but if you think of it as the furthest place we know we can land on, and explore, then it makes sense. If we can safely land, and return from Mars, then it makes going even further a possibility.

Yes indeed. But still, nobody is building residential neighborhoods on the top of the Everest or in the middle of Antarctica. Exploring for the sake of it is indeed a human instinct. The idea that we should build settlements for people who would live there permanently is plain silly. We have the obsession of repeating the Age of Discovery- but people should get the difference between discovering the Americas, with their wealth of plants, animals, land and waters, and settling a planet where there isn't a sign of life, not even air to breathe.

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

#216
post #133

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I'm skeptical because satellites, like pretty much any technology, tend to get smaller over time. I remember reading about how it was profitable for someone to buy up 4 geostationary slots and replace 4 satellites with 1 that was probably smaller than any of the 4 (because geostationary slots can be incredibly valuable). There are large bespoke payloads (eg JWST) but these are inherently so expensive anyway the launc…

> There are large bespoke payloads (eg JWST) but these are inherently so expensive anyway the launch vehicle costs almost don't matter. If launch costs are going to be $250M, you need a budget of that order of magnitude to make a mission viable. At that point, you might was well spend anywhere from $50M to $1B on the payload because that's where your budget is. Or, to put it another way, only payloads with a $50M to…

There are a couple of great examples of this playing out in "reverse" with some missions that, at pre-F9 launch costs could only afford to be on a rideshare or small launcher and thus were expecting to have to deal with all sorts of limits, only to end up being able to afford a dedicated F9.

There was IXPE, which has been the smallest dedicated payload launched by F9, which otherwise would've had to launch on a much smaller, air-launched pegasus rocket to get to the right inclination. I recall that they were able to simplify some aspects of the satellite deployment due to the roomier vehicle.

There was another mission, maybe Psyche? where the original plan would've required the risk of testing a new kind of engine to get to its deep space destination, but being able to get a dedicated ride instead, that risk was eliminated, such that it was going to be able to get there even if the engine tests failed.

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

#217
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 engineering challenge.

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

#218

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Honest question, did they sink the remaining fuel? Or did they just burnt all remaining fuel whilst hovering? I would imagine that's pretty toxic. Edit: Thanks for the answers!

Methane and oxygen are not very toxic.

Depends on how packed the room is ;)

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

#219
post #181

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"RSD"? (Rapid Scheduled Disassembly)

German V1 or V2, presumably.

Only the V2 is a rocket, the V1 is a flying bomb. They're both terror weapons, as actual products they have no direct military value, they exist solely in order to scare the shit out of enemy civilians, but liquid fuelled rockets are an invention with a whole lot of interesting practical applications - the V1 is just a bad idea (unless you have unlimited resources, which the Germans did not, and your goal is to terrify enemy civilians, which is not a legitimate military strategy).

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

#220
post #150

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Starship might honestly have a similar payload issue with the weird door design, the way it hinges up means you need a more complex release plan than most which just pop straight off the front of the booster. During the third test flight they also tested their weird side eject design for Starlink (or other flat pack style satellites) and the video looks like the door completely ripped itself apart.

The door design isn't final yet, there's no point in whining about it. They need tankers and landers for NASA contracts short term (neither of which require payload deployment), anything else is a nice to have that can be tinkered with on the side until it works.

The door is a major issue to using super heavy to deliver other payloads which is a goal long term and the need for a heat shield on the bottom makes it hard to make it fully open towards the front. Kind of need to have this fairly well sorted from the beginning because new designs mean new testing and certification which are expensive.
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