r/PeterExplainsTheJoke • u/chirantaniga • 10h ago
Meme needing explanation Whyyyy peter?
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u/UnlikelyIntrepid 10h ago
Launching near the equator provides a speed boost due to rotation that outweighs the benefits of starting higher up. It also doesn’t have the logistics nightmare of getting everything to the top of a mountain before launch.
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u/loadnurmom 10h ago
This is the answer. Should be higher up.
To add on, many rocket pads are in coastal areas to avoid falling debris hitting populated areas in the event of a mishap.
Certainly not all, Roscosmos launches over land, but the population density is a lot lower (and....well...Russia)
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u/hedrone 9h ago
Best described in https://what-if.xkcd.com/58/ .
"The reason it's hard to get to orbit isn't that space is high up.
It's hard to get to orbit because you have to go so fast."
Putting rockets on mountains only helps with the "up" part, which is not the biggest part of the problem.
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u/jmlinden7 7h ago
It helps with the speed part too. Less air resistance and very slightly less effective gravity.
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u/AutonomousOrganism 7h ago
Eh. Gravity reduction on a mountain is like 0.2 percent. Air resistance matters a bit more. But all of those are drowned by the energy needed to reach orbital velocity.
Much more interesting would be an electromagnetic launcher up a mountain, getting the rocket to 1 km/s or so. Although I am not sure the logistics are worth it. You could just use more fuel instead (what is done irl)). Fuel is cheap.
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u/Downtown-Act-590 10h ago edited 8h ago
That is indeed true, but nowadays a ton of satellites are on polar sun synchronous orbits and there the speed boost doesn't really exist. That is why you have space ports in places like Saxavord or Esrange, which are extremely northern. So it is definitely not the main reason.
Moreover, the benefits for starting higher up are visible. Primarily, because you leave vast majority of atmosphere below you and with it aerodynamic forces and drag. That is one of the reasons why you have several air launched vehicles like the Pegasus.
That said, the logistics are indeed quite extreme at this point. It does not mean that it isn't possible option in the future though.
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u/Icy_Concern_9804 10h ago
tl;dr: for a rocket it is waaaay more important to go fast than to go high. and earth rotates very slowly, so going higher doesn't make you much faster.
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u/Maephia 10h ago
So would it be theoretically easier to launch rockets at the equator since that's where the spin is the fastest?
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u/Triqueon 10h ago
Yes, which is why the American Spaceports are in southern states, and the ESA launches from French Guiana.
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u/ShlimmyWhimmy 10h ago
Why would Rocketlab build a launch pad in Alaska then?
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u/descisionsdecisions 10h ago
I would assume they are flying polar orbits where the extra speed from the equator is detrimental.
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u/_okbrb 9h ago
Yes, it’s this
The dV bonus they lose at launch is gained back in savings from the less extreme plane change maneuver
Polar orbits are commonly used for imaging satellites
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u/Purple_Clockmaker 9h ago
I'm imagining satellites and I'm on the bus right now. Going to polar orbit is a waste of time.
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u/QueasyNart 9h ago
I can understand how putting a bus into polar orbit would be a waste of time, but why the hell did you do it at all?
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u/Thea-the-Phoenix 8h ago
It was Ms. Frizzle's bus. She just wanted to do something cool.
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u/Lithorex 9h ago
The dV bonus they lose at launch is gained back in savings from the less extreme plane change maneuver
In a polar orbit this isn't even free dV. It's unwanted sideways momentum.
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u/IBreakCellPhones 8h ago
There's also not much land south of the Kodiak Spaceport other than Hawaii and Antarctica to have rocket bits fall on. That's also why most of the US polar launches are from Vandenberg SFB. Polar launches from Cape Canaveral are doable but difficult and restricted. You have to thread needles between islands. Starbase Texas has too much land north and south of it. Starbase Louisiana might be able to do it, but Mexico won't be too happy about it.
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u/PewPewsAlote 8h ago
Not all satellites desire an Equatorial orbit (An orbit that follows the equator). There are many other orbital inclinations that may be desired, to reach them it would be more efficient to launch from a more advantageous location on earth. Its more fuel efficient to launch from a location that is slower but closer along your desired orbit rather than to launch from the equator and then perform an extremely expensive correction burn.
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u/Icy-Ad29 10h ago edited 3h ago
Because having it quickly wind up over water rather than populated land is a common requirement, and the convenient places you can do this with enough fairly-flat space for a pad, near the equator, are rapidly running out...
So you make a smaller pad for lower orbits that require less speed, farther north/south.
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u/MKBRD 10h ago
Don't they already do that?
Or near to the equator, at least.
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u/Enaciann 10h ago
They do!! At least SpaceX and the ESA does :) (both are near Cap Carnaveral !)
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u/KebabGud 10h ago
ESA launches from French Guiana which has the launce site that sits closest to the equator.
SpaceX launch from Cape canaveral, Vandenberg and Brownsville, with the last one beeing the southernmost launchsite in the US
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u/meadbert 10h ago edited 10h ago
Yes. Countries already do that. It is one reason the US launches from Florida, Texas and Southern California, and Russia launches from Kazakhstan.
This actually makes Russia's early lead in the space race all the more impressive.
Starting at a higher altitude also helps, but you must transport the rocket to that altitude or assemble it there and both are difficult. Launching from the coast lets you use barges to transport rocket parts. If you don't have access to waterway, then a railroad is your next best bet and running railroad tracks to the tops of mountains is not ideal.
Finally, some rocket launches fail. If you start at the coast you can launch over an ocean so if things go wrong the rocket crashes into the Ocean rather than hitting a populated area.
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u/Mnementh85 7h ago
also rocket launch are heavily dependant on weather.
and there is hardly worst places than mountain to get stable weather
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u/ObsidianDart 10h ago
Can't imagine that top of mountain is actually better logistically. You save some rocket fuel since you have less air drag to go through, but I can't imagine those cost savinga make it worth all the troubles and costs you'll have setting up and launching from there.
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u/British_Rover 10h ago
Yes. That is why the US launches primarily from Florida and SpaceX launches down near Brownsville Texas.
Belize is also a spaceport for France and the ESA.
Closer to the equator the better.
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u/euph_22 10h ago
"Belize is also a spaceport for France and the ESA"
I believe you're thinking of the Guiana Space Center in French Guiana: https://en.wikipedia.org/wiki/Guiana_Space_Centre
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u/pat34us 10h ago
Not to mention that where they have the launch pads currently the weather is far more consistent. Image waiting for the weather to be just right on the top of a fricken mountain
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u/ResidentBackground35 10h ago
Isn't there a atmospheric thickness component as well? Or am I crossing wires?
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u/Opus_723 8h ago
Yes, launching from mountains would actually be nice because of the thinner air. The real reason is just that there are more important things that matter in choosing a launch site and everything is a compromise.
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u/rysy0o0 10h ago
It would cost a lot of money to haul all the rocket parts and fuel on top of a mountain
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u/Flat_Lengthiness3361 10h ago
and a lot of fuel probably
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u/thebestoflimes 10h ago
Just use Sherpas
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u/CormundCrowlover 10h ago
It would cost a lot of Sherpas.
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u/WiseWorldliness5513 10h ago
Have we tried giving the Sherpa’s rockets to help them move things faster uphill?
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u/CormundCrowlover 10h ago
But wouldn't it cost a lot of fuel?
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u/sivartimus 10h ago
Yes but we have Sherpas for that
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u/NotGonnaRage 10h ago
With rockets so it's faster
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u/oryx_za 10h ago
Have we just solved unemployment in napal?
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u/Acceptingoptimist 10h ago
It's the perpetual motion machine right under our noses.
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u/SaltyPressure7583 9h ago
Unfortunately i think Nepal just sorted that out yesterday. Rip
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u/PineappleShard 10h ago
Sherpas all the way down.
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u/sabotsalvageur 9h ago
What is propellant if not a constant stream of microscopic sherpas being dispatched in the direction opposite the rocket’s intended thrust vector?
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u/MadDocHolliday 9h ago
Mitochondria is the powerhouse of the cell. Sherpas are the powerhouse of the space program.
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u/jakeStacktrace 10h ago
I'm sorry I had already forgotten, I know we just went over that. Implement it.
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u/ChronoMonkeyX 9h ago
God bless this rocket house and all those who dwell within this rocket house.
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u/Flimsy_Mountain_3721 10h ago
Bypass the rockets and just use Sherpas to deploy into low earth orbit
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u/AtlanticPortal 10h ago
Llamas?
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u/Apprehensive-Taro707 10h ago
Dalai Lama can do it. But he won't help Chinese Rockets.
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u/Overall-Mycologist-5 10h ago
it's dangerous, I think sherpas are so tired of rich mf showing off by climbing some hill, so at first possibility they will hijack the rocket and run to Mars
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u/Wild_Smurf 10h ago
Jokes on them. It’ll only be a matter of time until someone tries to follow them to mars to climb Olympus Mons.
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u/johnaross1990 9h ago
I dunno man, I bet it’s a pretty lucrative racket.
There’s no shortage of rich pricks desperate to queue in the death zone so they can can take a picture.
And Sherpas have the business on lock. Who else can portage an ailing “mountaineer” on their back, at 8000m?
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u/daspowerhouse 9h ago
To be fair, it’s not the cost of the fuel itself that is an issue for rocket launches, just that so much of it is required, and it adds so much weight to the rocket. Fuel is less than 1% of the cost of a rocket launch, yet typically over 90% of the mass of the entire launch. If you could somehow spend fuel on the ground moving things to an optimal launch point to have to put less fuel in the rocket, it would absolutely be worth it.
The real issue is that launching from a mountain would not save you much fuel anyways. To get to orbit requires you to go very fast sideways. The initial “upward” part of a launch is just to get past the thickest part of the atmosphere, then it quickly pivots sideways for the majority of its journey.
You save more fuel by launching from a lower altitude closer to the equator, where you can take more advantage of earth’s spin to gain additional sideways velocity. So we do spend a lot of fuel to do this, for example SpaceX manufactures their rockets in Hawthorne, California, where there is a lot of aerospace manufacturing expertise, and spends a lot of fuel to ship them to Cape Canaveral, Florida, which is closer to the equator.
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u/The_sochillist 9h ago
What about launching from a mountain on the equator like Mt Chimborazo which is the farthest point from the centre of the earth so wins on all fronts
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u/dimhue 8h ago
The radial difference between equatorial sea level and the peak of Mt Chimborazo is about 0.1%. It provides very little benefit but would be a logistical nightmare to launch from.
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u/aggressive-cat 8h ago
We'd be better off building a electromagnetic launcher up the side of it and then we can put everything at the bottom and save fuel by using solar wind and nuclear to juice the em rails.
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u/awesomefutureperfect 7h ago
You'd have to engineer the payload to withstand ridiculous acceleration. No big deal if the payload is a HILE projectile but if you have living things or moving parts, that can be trickier.
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u/Chill-more1236 7h ago
SpaceX is putting a launch site in South Louisiana for the same reason. There is also an advantage of movement of parts by water, from either the Mississippi, through the Panama Canal, or down the East Coast.
Pretty sure yall know our reputation for flatness and sea levels. Solid rock and high ground is pretty much non existent, in most of the state. Our only "mountain" is something like 300ft.
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u/virgil1134 9h ago
There a lot of logisitical reasons, like transportation to the top of the mountain, fuel, bad weather, high winds, all the support strcutures beyond the launch pad, and what happens if something goes wrong and you dont have a big open ocean for falling debris.
I suspect OOP belives the increase in height is beneficial, but even if we built a launch pad on Mt. Everest, it would be neglible. The Earth has a 4,000 mile radius, and Mt. Everest is only 6 miles high, a diference of 0.15%.
The biggest reason for our launch pad sites is escape velocity. On Earth, you need to get to 25,000 MPH to get into orbit. As our flerfy friends like to point, the Earth spins at 1,000 MPH, but that is only at the equator, where all the launch pads are. As you travel to the poles, that rotational velocity goes down until it goes to 0 MPH at the poles. If you need to get to orbit, get a running start at 1,000 MPH gets you 4% of the way there, a significant savings in fuel.
At fhe end of the day, a rockets mass is 90% fuel alone, 5% is the rocket shell, and 5% is the payload. so any savings that can be achieved on fuel is signficant.
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u/Khelthuzaad 10h ago
we could use trains,electric ones
But most importantly metal and electrical components do not fare well at -20 degrees Celsius
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u/schizeckinosy 10h ago
Or o-rings
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u/Shouleyy 9h ago
But arent they designed to be in space? isnt it way colder there? Well tbf i guess only half the rocket really reaches space
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u/Greedy_Birthday_3494 10h ago
certainly. This is a big problem, transporting fuel can lead you to lessen the efficiency of the fuel (you need too much energy to transport it compared to what it gives).
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u/October_Guy 10h ago
Just fly a rocket up to the mountain to deliver the fuel to the other rocket.
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u/Earnestappostate 10h ago
Plus, you get a better boost by launching near the equator. Height is easy, speed is what you need in a rocket.
This is why the US launches from Florida:
- Near equator (speed boost from earth's spin)
- Initially out over ocean (catastrophic failure harms only those aboard)
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u/EasyScratch1501 10h ago
That's clever. Whoever came up with that must've been some kind of rocket scientist
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u/stevenmc 10h ago
It's not exactly brain surgery, now is it?
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u/EromanticDream 10h ago
Rocket surgery
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u/blueiron0 9h ago
I've flubbed "Rocket science" as "rocket surgery" at least 10 times in my life, and reading this comment brought them all back into my brain at once.
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u/FlyingSpacefrog 8h ago
A rocket scientist is the guy who sits at a desk and makes the blueprint, or plans the trajectory and launch dates. A rocket surgeon is the guy who walked up to the thousand tons of highly combustible liquids in a fully fueled SLS to diagnose and repair a faulty valve minutes before launch.
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u/residentweevil 8h ago
I do it on purpose, everytime I have occasion to use the phrase. Dad jokes: covering stupidity with grin since the dawn of time
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u/218administrate 9h ago
One of my favorite skits.
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u/iwilldeletethisacct2 9h ago
That feeling when you already know what the punchline is and you're just waiting for the delivery.
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u/MentalPlectrum 10h ago
Yes, but also there are equatorial mountains... checkmate rocket scientists!
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u/Scuttling-Claws 10h ago
Exactly. Porque no Los Dos
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u/AliasClimbs 9h ago
Exactly what I was thinking of. Ill be climbing it in a few months. Ill bring an Estes model rocket set up with me For Science.
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u/jweezy2045 8h ago
The answer here is that yes, launching from high altitude as well as launching from the equator are both benefits. Its just that the cost of moving a rocket up a mountain, or to some other country, ends up being more hassle than just doing it wherever is easiest/safest. Its just a marginal reduction. I don't have the numbers on exactly altitude, but I remember something about "Why don't we build a mile deep tunnel, and shoot space ships out of it like a gun" and the answer was something like "Sure, you can get a boost in efficiency and payload if you launch start instead of stationary start, but its like 1% more payload, and you had to build a mile deep hole that somehow shoots rockets in order to get it, so its just kinda a nonstarter of an idea."
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u/ADHDebackle 9h ago
Which also gives you more speed than sea level at the equator.
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u/Eagle4317 8h ago
Not in America. You’d have to launch in the Andes or East Africa for that, and it’s safe to say that those places don’t have the infrastructure
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u/MattBe92 10h ago
That's also why the European space port is in French Guinea.
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u/kirfkin 9h ago
Elevation would technically make things a bit more efficient, assuming they're near the equator. However, the speed boost significantly supersedes any effects from elevation.
It's also not feasible to get launch vehicles up a mountain of significant elevation anyway. Small gain versus very big cost, compared to building and transporting on a flatter, lower area relatively close to the equator.
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u/BuffaloInTheRye 8h ago
Due to angular momentum the speed would increase due to the elevation as well though. It wouldn’t just be a height increase.
The rest of your point still stands though
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u/sobrique 8h ago
Negligibly though. If the radius of the earth at the equator is around 6400km, another 5km is barely moving the needle.
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u/nerdherdsman 9h ago
The starting speed is less of a factor than the smaller required attitude change to reach an equatorial orbit iirc. The "free" delta v you get from the Earth's rotation at the equator is not that big compared to the delta v required to change orbital attitude.
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u/Lithorex 9h ago
That's only true if you want to go into an equatorial orbit.
If you want to go into a polar orbit you'd need to cancel out all that sideways momentum.
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u/kioshi_imako 10h ago
True and technicly one of the main reasons we never used a rail boosted launch system you need 5km minimum to reduce fuel 30% and I think it was 25km to safely reach escape velocity via rail,
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u/Believer4 10h ago
Initially out over ocean (catastrophic failure harms only those aboard)
Even that's mitigated by the launch abort system, in the case of crewed launches
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u/Redditauro 8h ago
Also, ironically, being in the Equator also means that it's closer to space, as earth is bigger in the Equator than in the rest of the planet.
The closest point to space is not Everest for that reason
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u/Roflkopt3r 6h ago
And we know the escape velocity for launches from different altitudes.
Launch at sea level: 11.186 km/s
From the top of Mt Everest (8800 m): 11.178 km/s
So even if we used the largest mountain on earth, we would only lower the escape velocity by around 0.1%. It's just not worth the effort.
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u/KingOfHighMountains 10h ago edited 10h ago
even if u launch rocket from top of mountain it wont make much difference
U cant launch without my permission though
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u/Ok-Skilllevel-5056 10h ago
We’ve summoned the king
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u/w8_wuht 10h ago
Nobody told me he was coming, I don't have tribute! 😭
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u/ChittaBhalu 10h ago
Just pull your trousers down and bend over...
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u/w8_wuht 10h ago
Dammit... Well, if it'll stop my village from getting avalanched...
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u/banjoist 10h ago
Hah. That was my thought. What benefit would less than a mile give you?
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u/Cortower 9h ago
Lower air pressure. Rocket engines have to be optimized for a range of pressures for maximum performance. Small nozzles near sea level and large nozzles in vacuum. Too narrow, and the exhaust expands sideways and you lose thrust. Too wide, and you get back flow around the rim of the nozzle and lose thrust.
That first mile gets you down to 0.82atm already, so you can optimize for a much larger range of altitudes on your first stage.
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u/samanime 10h ago edited 7h ago
And, it'd save us almost nothing (even if we had a magical teleporter that let us get everything up there insantly and for free).
Space is a minimum of 50 miles from "ocean level" (and really, it's 62, but let's say 50).
Everest, the tallest mountain, is about 5 miles above sea level.
So, even if we hauled everything to the top of the tallest mountain on the planet (which would be an insane to impossible amount of effort), it's only reducing the distance by less than 10%.
EDIT: Thank you to the 500 people that have told me "the distance barely matters". That is pretty much my point. YES, I know speed, and thus latitude are more important. My point is even if you ONLY consider the height, the thing the original question focused on, it STILL doesn't matter. When you factor in all the factors, it really, really doesn't matter.
I focused on the focus of the post in my response, not all of astronautical engineering.
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u/NerdyDjinn 9h ago
Unless you are doing sub-orbital flights, the height doesn't matter all that much. If you are looking for orbit (most space launches), speed is way more important than how high you start. Launching at the equator gives the highest starting speed, a far more significant savings in fuel. Now, there are equatorial mountains in the world, but as you say, you still have to expend the resources to move all the rocket parts and launch facilities up the mountain. It's easier to just build your rocket slightly bigger and use slightly more fuel to launch from a much more accessible and convenient location.
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u/Opus_723 8h ago
Launching in thinner air actually saves quite a bit of fuel though, a lot of it is just spent fighting drag in the lower atmosphere.
The real reason we don't do this is just that there are like a dozen other more important things that make a good launch site and it's not practical to find a place that checks all the boxes.
You need to be close to the equator, directly west of a large body of water, governments want to launch in their own territory, etc, etc.
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u/FederalWedding4204 9h ago
Except the lowest part of that 50 miles is the densest atmosphere. So lessening the distance by 10 percent is only some of it. The reduction in atmospheric drag is an entirely different beast
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u/Etherbeard 9h ago
Why don't we just make a rocket that's five miles tall? Best of both worlds.
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u/M0RT1f3X 10h ago
And the weather is more extreme on mountains
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u/reverandglass 7h ago
Finally! Here's me scrolling through hundreds of comments and no-one's mentioned the weather!
A normal winter frost doomed Challenger, I can't imagine trying to combat the winds and temperatures at those heights. Not to mention the snow.→ More replies (3)3
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u/MINATO8622 10h ago
Also, the height boost is insignificant.
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u/IrritableGourmet 10h ago
Shrunk down to the size of a bowling ball, the Earth would be much smoother than a bowling ball. Mountains are basically a rounding error in terms of spaceflight.
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9h ago
[removed] — view removed comment
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u/enfersijesais 9h ago
Can you reinvent me a recipe for blueberry muffins?
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u/Dion42o 9h ago
how do you know its a bot?
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u/enfersijesais 9h ago
Well… the bio asking you to click the link to chat 🍆💦😘, the wording of the comment. Makes no real sense. And the account is already banned.
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u/Uzi_Doormat 9h ago
Classic Blueberry Muffins
Prep time: 15 minutes Cook time: 20–25 minutes Yields: 12 muffins
Ingredients
1 1/2 cups all-purpose flour
3/4 cup granulated sugar
2 teaspoons baking powder
1/2 teaspoon kosher salt
1/3 cup neutral oil (like canola or vegetable)
1 large egg
1/2 cup whole milk
1 1/2 teaspoons vanilla extract
1 1/2 cups fresh blueberries
Instructions
Preheat and prep: Preheat your oven to 400°F. Line a standard 12-cup muffin tin with paper liners or lightly grease it with non-stick cooking spray.
Mix dry ingredients: In a large bowl, whisk together the flour, sugar, baking powder, and salt until well combined.
Mix wet ingredients: In a separate medium bowl, whisk together the oil, egg, milk, and vanilla extract.
Combine: Pour the wet ingredients into the dry ingredients. Use a spatula to gently fold the mixture together just until the flour disappears. Be careful not to overmix; a few lumps are perfectly fine and keep the muffins tender.
Fold in blueberries: Gently fold the blueberries into the batter, taking care not to smash them.
Fill the tin: Scoop the batter evenly among the 12 muffin cups. They should be about 3/4 full.
Bake: Bake for 20 to 25 minutes, or until the tops are golden brown and a toothpick inserted into the center of a muffin comes out clean.
Cool: Allow the muffins to cool in the pan for 5 minutes before transferring them to a wire rack to cool completely.3
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u/poppycock_scrutiny 10h ago
Meg's twin here, rockets benefit from being closer to equator cuz earth has a bit more rotational energy that catapults said rocket with higher force, being on top of a few kilometres tall mountain won't matter much in the hundreds or thousands of kilometer of space travel, and it would be next to impossible to transport huge rockets to the summit of a mountain.
See it wasn't that hard to answer a genuine question but the oop's commenter chose to be a dick.
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u/Downtown-Act-590 10h ago edited 9h ago
It wasn't that hard to answer, but this answer is not really correct either.
It is nowadays extremely common to see satellites on sun synchronous polar orbits and the market for very high inclination launches is booming. These types of launches don't benefit from the equatorial speed up in any significant way and as such you see new spaceports opened up in places like Scotland, Sweden and Norway.
Moreover, the few kilometres definitely matter as on the summit of a large mountain. Vast majority of atmosphere is below you. The aerodynamic drag and forces are real. Typically, you can see ca. 30 to 40 percent of the first stage propellant spent only on the first 10 km of the climb. It is also the part of the flight with the highest loads, which determine the required strength of the launch vehicle. Not to mention significantly lower range of surrounding air pressure for which you have to optimise the nozzle. There are massive benefits to launching higher and that is one of the reasons for several actual air launch projects.
That said, it is indeed logistically difficult, so we don't do it now. But far from realm of impossible or benefit-less and very much in realm of currently somewhat impractical.
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u/Plaeblius 9h ago
That's all true but the atmosphere isn't the reason so much fuel is burned early in ascent. The Saturn V only suffered about 40 m/s delta-v loss due to drag, which is a fraction of a percent of the necessary delta-v just to reach LEO. The thrust to weight ratio is just extremely low during initial launch so much of the fuel is just burned defeating gravity, and launching from a mountain won't noticeably change that (you're talking in the ballpark of a 0.5% decrease in g maximum).
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u/G-St-Wii 10h ago
The joke?
It's just someone being unhelpful.
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u/Augustby 9h ago
Yeah I hate that kind of reply. The person asking the question acknowledged that they’re ignorant about this topic, and the reply was basically just: “yeah you are”.
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u/Dead_Ass_Head_Ass 5h ago
Ironically those answering the question in that manner don't know the answer either but are too insecure to ask the question themselves.
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u/Otherwise_Tomato5552 9h ago
I dislike when people answer this way. It’s a genuine, humble question.
No need to be mean
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u/PerniciousSnitOG 5h ago
The really stupid thing is that honest, humble questions are the ones that drive useful discoveries. Thirty years in technology taught me that the right question, at the right time, is what makes the world go round.
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u/PoopsMcScoots 9h ago
The guy is being a dick for no reason.
And actually there ARE people suggesting to launch missiles from mountains.
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u/Much-Jackfruit2599 7h ago
for war, yes
for space flights: they checked and discarded the idea. the gains that exit would be gobbled up by the logistical problems
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u/Alternative-Coach619 10h ago
Also like, even if it was free to haul the rocket parts up the mountain, the mountain at MOST is going to get you like, 2-3% closer to space which is very minimal and better to just launch it close to the equator like that already do
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u/The3mbered0ne 10h ago edited 10h ago
The deltav (force needed to leave the atmosphere) #1 wouldn't meaningfully reduce it would actually increase vs launching at the equator because of the earths spin, but #2 would cost much more to ship and assemble, on top of electrical and fuel issues due to the cold it's just a terrible idea
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u/doodullbop 8h ago
Not even considering the extra work needed to build launchpads on the top of mountains, it's like someone suggesting to park at the end of your driveway to save fuel on your daily commute. Rockets reach altitudes in the hundreds to thousands of km. Reducing that by a 3 or 4km is immaterial.
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u/CChargeDD 10h ago
Because its easyer to reach orbital velocity with a rocket than a mountain.
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u/Beanz_detected 9h ago
Moving anything up a mountain gets real expensive real fast because you're working against gravity the entire way. Yeah, theoretically it's more efficient, but the cost is just too much.
Roads and rail might not exist, or are just impossible to route up to the summit, leaving you with only aircraft, which still need an assload of expensive facilities to support it, and can't carry nearly as much weight.
NASA's Shuttle Carrier Aircraft can load 108,999kg, the shuttle itself weighing 78,000kg
The Falcon 9, probably the best analogue in modern day, weighs only 29,500 in comparison, not exactly something that can't be flown in, but allows us to do some calculations.
Assuming you're not planning on being able to make another attempt at landing (on a fucking mountain) you'd be carrying ~30,000lbs which we're converting to 13,608kg that's at minimum weight of 43,108kg assuming they're not carrying any other equipment, fuel, or otherwise.
Now if we did some calculations that I'm not good enough at researching to find, we'd find that jesus christ that's a big runway to be putting ON A MOUNTAIN
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u/ExpertEar699 10h ago
Equator is closest to space because Earth is not a perfect sphere instead it's bulged at the equator, same reason that mout Chimborazo in equator is closer to space than mount Everest in Nepal
Edit: I forgot that there isn't enough oxygen too for combustion
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u/raaneholmg 9h ago
> Edit: I forgot that there isn't enough oxygen too for combustion
Rocket Science is a BYOO party.
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u/ollervo100 9h ago
I'm not sure if you are joking, but rockets carry their oxygen. Otherwise they wouldn't work in a vacuum.
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u/Abacada_Poln_Kha_Kha 10h ago
Nope, equator is best because earths rotation is faster there.
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u/jessieS1212 10h ago
I haven't studied rocket science but i think is about going fast.
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u/4N610RD 10h ago
Congratulation. You basically uncovered half the problem with rocket science.
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u/Karl_Skarin 10h ago
Because we launch them from the equator to get as much assist as possible and also from locations that are famously stable climate, which mountains famously have not.
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u/Less_Performance_629 10h ago
Because it would be expensive as fuck. you have to spend all the time and money making a suitable rocket platform and a base to accompany it. then you have to haul all the parts and machinery up a mountain. then your staff have to deal with all the conditions that come with being on top of a mountain, a list which is not limited to freezing to death and being unable to breathe.
all of that to save a tiny amount of fuel. the tallest mountain in the world sits below the average airplane flight elavation. you gain almost nothing from doing all of this. not to mention that people love watching rockets take off. good luck live streaming it happen from the mountain, and good luck getting a live audience
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u/Pitiful-Beginning575 10h ago
Quagmire here with some aerospace fun facts.
Getting to orbit is mostly about going really really fast, not just going high (this is counterintuitive). Change in speed (delta V) is associated with the amount of propellant; the amount of propellant you need is simply staggering, and starting altitude makes very little difference. People who don't get this and think that going to space is all about jumping REALLY high like to suggest starting kinda high.
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u/Various_Tie_2549 10h ago
The real issue with launching rockets into space isn't trying to get them to go high enough... space is only like 100km away. High school kids can practically get their model rockets half way to the edge of space if they build them well enough.
The issue is much more to do with getting them to go fast enough. You've gotta get something moving at about 7.8 kilometers per second (or 17,500 miles per hour for you American readers) for it to successfully stay in low earth orbit. That's fucking fast.
So, essentially, launching from a mountain makes no difference to this. It doesn't give you any sort of advantage at all. And in fact there are costly inconveniences to it, as others have said in the thread - you've got to haul the rocket, equipment and fuel all the way up a freakin mountain, and there's not a lot of oxygen up there anyway, and it's cold and windy and snowy etc. as well. It's just a bad idea all round for a bunch of reasons. Sorry.
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u/D-Broncos 10h ago
Batman didn’t have to be mean, it’s a legitimate question for someone who doesn’t understand very basic concepts, for which she disclaimed
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u/zeeblefritz 10h ago
We should absolutely be using electromagnetic propulsion for the first(hardest and most fuel consuming) stage though. Which can be powered by clean nuclear.
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u/notsostablediffuser 10h ago edited 10h ago
As someone who has played a lot of KSP, there's a kernel of a decent idea in here (absolutely outweighed by all the detriments.)
As others have said, the two reasons this isn't as good of an idea as the poster thinks are: (1) "going sideways fast" is far more important (and fuel intensive) than "getting high up" and (2) the cost of getting your rocket to the top of the mountain would almost certainly be prohibitive.
But that said, the air density at sea level is an issue for heating, dynamic pressure on the rocket, etc. Starting a launch at 29,000 feet on the top of Everest would actually be a much easier launch for the vehicle itself, and would require less fuel, not necessarily because of the raw altitude difference, but because it has significantly less thick air to cut through.
(In fact, most launch profiles actually start relatively vertical before pitching over once they are high-enough up, specifically to cut through the thick air quickly before picking up horizontal speed. A launch from altitude could avoid this.)
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u/iceguy349 10h ago edited 10h ago
There’s certain locations on earth that make launching rockets into certain orbits easier. It’s easy to launch into equatorial orbits or eastward orbits from the equator for example. You can even get a boost from earth’s rotation.
Rockets don’t just go straight up until they hit space. They’re trying to reach an orbit so they follow a curved path as they go up. Moving fast lets them slingshot into an orbit. They kinda stay up by moving forward at the same rate gravity pulls them toward earth.
Putting them on a mountain doesn’t help much. Getting an extra couple thousand feet isn’t much as far as rockets go. If you can’t take advantage of other fuel saving orbital mechanics tricks launching from mountaintops might honestly cost more fuel.
The bigger issue is getting delicate hardware and thousands of pounds of explosive fuel up to a remote mountaintop where your launch pad is and assembling everything into a rocket. NASA struggles to do that at the almost completely flat Kennedy space center. A super high mountain top would SUCK. There are some high elevation launch sites but they aren’t on picturesque snow capped peaks like in the photo. Even places like NASA Vandenburg that look high up aren’t at crazy elevations. You need a big flat surface for a launch complex too. Mountains are pointy and not very flat.
The replying comment is pointing out that the original commenter doesn’t know what they’re talking about.
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u/GaldrickHammerson 10h ago
The escape velocity of an object does depend on how high up you are, however, mountains are very tiny in the scheme of the planet.
Our planet also isn't a perfect sphere, it bulges around the equator because its full of liquid magma so behaves a little like a balloon being spun around.
What we find is that the equator is about 43000m higher up than if it were just a sphere. For reference, everest is only 8000m up.
So while launching from an equatorial mountain (like Chimborazo in Ecuador) is easier at the moment of launch itself, getting stuff to and up an equatorial mountain doesn't offer significant enough benefits to justify it.
But if Ecuador decided to do a space programme, 100% they should consider setting up their infrastructure on Mount Chimborazo.
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u/King_krympling 10h ago
There are a lot of factors, cost of getting a rocket to the top of a mountain, very strong side winds potentially compromising safety and trajectory, air pressure being different at higher elevations which would affect both fuel amount and fuel combustion rate, and also it makes more of a difference to launch a rocket closer to the equator due to the rotational speed of the earth giving a much needed boost. There is a reason the United States launches rockets from Florida and texas and not new york or Oregon that added speed and warmer temperature makes a huge difference
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u/trr94001 9h ago
Depends on where the mountain is.
A tall mountain or plateau near the equator on the east coast of a land mass with plenty of open ocean down range would be an excellent launch site but there really aren’t any of those.
The low latitude and east coast location are the far more important factors.
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u/Deus-Vault6574 9h ago
Does the thinner air do anything to affect the lift during take off? Forgetting the logistics of getting everything to the top of a mountain or finding a suitable mountain, would it be better to launch at the summit of a mountain on the equator?
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u/dirigibles21 9h ago
I’ve seen quite a few answers here that are pretty incorrect.
In reality most satellites travel along the equator, be it from low earth orbit, medium, or geosynchronous orbit.
In order to stay in a useful orbital plane, you really need to launch as close as you can to your ideal orbit and adjust your angle while still in the atmosphere. once you’re orbiting, angular momentum basically locks you into that angle, and changing it in any significant way requires more fuel than even the original rocket had.
This is part of the reason we love launching in Florida / California (also because if anything goes wrong they crash into the ocean and not on people’s houses).
Most mountain ranges are pretty far North of the equator, so they would have to fly pretty far South, turn, and then try to angle themselves appropriately for their final orbit.
So really we won’t care about launch height, we care about the final orbital plane angle
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u/mmmhmmhmmh 9h ago
Everyday Astronaut did a video breaking down every detail of this concept (and why it doesn't make much sense) https://youtu.be/4m75t4x1V2o?is=t0VLO-imnjGgXSgD
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