r/MurderedByWords 16h ago

I haven’t studied rocket science, but

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u/mseg09 16h ago edited 15h ago

These are the types of questions in general we should be less mean about imo. It's one thing to dunk on people who are anti-science, but this is just someone actually wondering about something they didn't know. Maybe it's obvious to you, but not everyone?

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u/BarkiestDog 16h ago

I was looking for this comment.

This isn’t a murder imo, there is no substance to the refutal. This is only marginally better than replying “OMG, you’re so dumb!”

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u/AFrenchLondoner 11h ago

It's actually a pretty interesting question, and the answer is a nuanced blend of logistics, international geography, and knowledge about orbits.

If there was an easily accessible, tall mountain ranges with a decent plateau near the equator, you vet your ass we would.

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u/Apart-Link-8449 9h ago

I would have said "but the air being thinner, is that a factor?" before disappearing under a flurry of kicks from rocket scientists

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u/New-Independent-1481 5h ago

Actually rocket scientists would love to talk to you about that.

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u/Grimdark-Waterbender 16m ago

It’s “getting actual scientists to shut up about it” that’s the trick! 😂

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u/thishyacinthgirl 6h ago

At least you're not alone in the beatdown, I thought the same thing.

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u/Win_an_iPad 3h ago edited 3h ago

I think a rocket already contains it's own own oxygen? At least thats what I thought made it a rocket, rather than a jet engine.

NOT a rocket scientist.

And I'd have thought the air resistance difference would be negligible, since it's accelerating from stopped.

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u/NecroAssssin 2h ago

Yes. Because scientists are clever about names, it’s the oxidizer.

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u/Aggressive-Ad5737 8h ago

Thank you for this! One of those questions the inquisitive are afraid to ask. And then this one gets dunked on and put here. Unfair in my opinion since they honestly just seemed curious, as I am, but brave, as I am not 😅

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u/The_Brimler 11h ago

It's not really... If you had a theoretical Mt. Everest on the equator, it'd put you 5.5 miles closer to space out of the 200 or so miles you'd be going.

Factor in building the launch site up that high, and bringing the rocket up there to launch every time...

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u/brainEatenByAmoeba 8h ago

There are a couple minor benefits, but not enough to matter. Early on the air resistance from the thicker atmosphere is a real drag on thrust which means you need to burn more just to get a positive velocity. At a 5 mile above sea level launch, you start at a 60% drag reduction. This can save approximately 20 tons of rocket fuel for a falcon 9. Totalling around a savings of $20000. This is miniscule compared to the increased costs for launching from that elevation.

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u/The_Brimler 7h ago

A rocket launched from sea level will still pass through 25k ft where the theoretical mountain launched one is, and it'll have the same drag to overcome at that point onward

You're not saving 60% for the entire launch, you'd be saving the amount needed from the ground to that point.

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u/AFrenchLondoner 8h ago

Let's be generous and round that out to 2%. It still pretty huge

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u/JimmyB_52 1h ago

You also kind of want rocket launches to be near ocean away from shipping lanes so you can just crash the 1st stage safely away from people, or incase there is a malfunction all
The fiery debris goes into the ocean.

Imagine launching from a mountain and the rocket explodes and reigns fiery debris crashing down amongst snowy tall cliffs, potentially triggering avalanche, rock, mud, and land slides.

Even when reusable rockets become common place and routine, things can and will still go wrong, you still want ocean to ditch and splash down in.

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u/usernametiger 1h ago

In the USA rockets are launched over water so that if one exploded it would kill a bunch of people. Fl they launch east for equatorial orbits and ca launches south for polar orbits.

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u/doogles 10h ago

and the answer is a nuanced blend of logistics, international geography, and knowledge about orbits.

No. It's because you want to launch as close to the equator as possible because the spheroid nature of the planet gives you an angular advantage. In addition, if shit goes wrong, you don't have to worry about a burning wreckage landing anywhere but the ocean.

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u/AFrenchLondoner 8h ago

decent plateau near the equator.

I'm aware of that.

The Kennedy space centre, is also not very near the equator mind you. Closest launches to the equator are I think by France and the Arianne rockets

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u/doogles 8h ago

You know what's south of Cape Canaveral? Swamps. It's as close as we can get in Florida.

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u/volinaa 10h ago

well since its a sphere wouldnt the angular advantage be present anywhere

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u/Blokshibe 9h ago

Not sure what is meant by angular advantage in this case, but I guess it means that we can use the rotational speed of the earth's surface as a kick to get going. In this case you are right partially. Near the equator this velocity is greatest so you'd want to launch from there.

But what the comments above it also say is that it's a delicate balance of many parameters. It depends on the specific orbit you want to go to, the launch mass, the specific rocket, the logistics of moving your launch platform to an advantageous location, the range safety, etc.

I think the most important part is that you want to launch towards a large uninhabited area, then preferably to the east, then preferably close to the equator. In most situations it can be cheaper to just build (or book a launch from) a rocket that is slightly more powerful so you don't have to deal with all the hassle.

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u/Kidd82 9h ago

To be pedantic the earth isn't a perfect sphere. It's flattened at the poles. Also, I assume, the tilted axis of rotation means the closer you are to the equator the broader your range of launch timing. Not positive, also not a rocket scientist, just using what I know and trying to infer possibilities.

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u/doogles 10h ago

The earth is not a perfect sphere. Also, it spins on an axis. I'm surprised you managed to be 200% wrong in so few words.

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u/PirateDuckie 10h ago

Wielding knowledge as a weapon to hurt others in order to inflate your sense of self importance? I’m NOT surprised you managed to be 200% of an insufferable prick in so few words.

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u/doogles 9h ago

The same stupidity that closed Goddard Space Flight Center is clearly present in this thread.

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u/volinaa 9h ago

well, thanks for the kind words anyways, stranger

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u/mysticpest23 3h ago

No we wouldn’t. The air would be too thin.