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Saturn V fuel consumption in elephants. (i.imgur.com)

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[–]KrAzYkArL18769 113ポイント114ポイント  (27子コメント)

So, I'm assuming each elephant represents one-elephant's-mass-worth of fuel consumed? I doubt they would use volume.

[–]pbmonster 69ポイント70ポイント  (14子コメント)

Doesn't really matter to much. Elephants can swim under their own power, meaning their density is very close to that of water.

Saturn 5 burns liquid hydrogen and liquid oxygen at ideal mixture, exhausting water. Elephants,LH2/LOX fuel and water all have about the same density.

[–]haamster 30ポイント31ポイント  (1子コメント)

First stage was RP-1 and liquid oxygen, so water vapor, un-burned hydrocarbons, carbon monoxide, and carbon dioxide were all being exhausted.

Now I'm three levels deep in this and forgot what the original point was. I'm gonna go take a nap.

[–]HeyCarpy 15ポイント16ポイント  (0子コメント)

We were putting men into space on elephants. Hope that helps.

[–]KitsapDad 1ポイント2ポイント  (0子コメント)

Saturn stage 1 burned RP-1 (Kerosene).

[–]tiedyechicken 4ポイント5ポイント  (10子コメント)

Haha, you forget that the water coming out of Saturn V is running at a couple thousand Kelvin, and therefore is much less dense. :)

[–]Goobyalus 16ポイント17ポイント  (8子コメント)

It's not stored at a couple thousand kelvin, is it? We're talking fuel, not exhaust.

[–]tiedyechicken 13ポイント14ポイント  (7子コメント)

You're correct, the fuel/oxidizer is stored at roughly 19K and 89K, respectively, which puts it at slightly more dense than room temperature water. Since the elephants are exhausting out of the nozzle, I assumed that was our reference. Sorry!

[–]Goobyalus 4ポイント5ポイント  (5子コメント)

Whoa, that's not a temperature that I would have thought either. Why so cold?

[–]ScaryCookieMonster 7ポイント8ポイント  (1子コメント)

Boiling point of Oxygen is 90K, so 89K is to keep it a liquid in the tank. Same deal for Hydrogen--boiling point of 20K.

(I'm assuming the 19K figure quoted is for the liquid hydrogen and not the RP-1 fuel, which since it's related to kerosene I think is liquid at room temperature.)

[–]Goobyalus 0ポイント1ポイント  (0子コメント)

I assume it's also under very high pressure though. Do the phase curves for oxygen and hydrogen stay close to those temperatures? Or are we trying to keep all the fuel in liquid form while the fuel is consumed?

Edit: based on /u/tiedyechicken 's response I assume we want it to remain liquid.

[–]j3rmz 3ポイント4ポイント  (1子コメント)

I think partly for storage purposes. The colder it is, the more dense it is, the more they can store in a confined space. I'm sure there's some thermodynamic reasons for it as well but I don't know enough about it to be sure.

[–]tiedyechicken 6ポイント7ポイント  (0子コメント)

It's certainly easier to pump, as it'll become gaseous if it's any warmer.

[–]ugg116 2ポイント3ポイント  (0子コメント)

More dense => more fuel fits into the tank => more delta-v

[–]theKalash 0ポイント1ポイント  (0子コメント)

Because Hydrogen and Oxygen at normal temperature would be gaseous and take up way more volume.

[–]Adalah217 0ポイント1ポイント  (0子コメント)

So are the elephants. Liquid elephants.

[–]carsgobeepbeep 4ポイント5ポイント  (0子コメント)

I think it would actually be pretty similar for the first stage whether represented by weight or volume.

  • The density of water is 1000 kg/m3.
  • The density of an elephant (and of most animals) is not terribly different from that of water -- just slightly less.
  • The density of RP-1 used in the Saturn V first stage is around 820 kg/m3, or 18% less than water.
  • Density of liquid oxygen, also used in first stage, is 1155 kg/m3, or 15.5% more than water.

(Now for the 2nd/3rd stages which were used outside of earth atmosphere, the difference becomes more significant as they used a mix of liquid oxygen and liquid hydrogen.)

  • Density of liquid hydrogen is 71 kg/m3 -- wayyyy less than water

[–]drunkenstarcraft 9ポイント10ポイント  (3子コメント)

I was actually thinking it might be an elephant's-worth of energy, like the total energy you would get from combusting one elephant.

[–]Jaspersong 17ポイント18ポイント  (1子コメント)

that would need wayyy more elephants

[–]Kilt_Dropper 5ポイント6ポイント  (0子コメント)

If we converted all the elephant's mass to energy then we would need far less than 1 elephant.

[–]daveqwerty 0ポイント1ポイント  (0子コメント)

It would need to be a big calorimeter to fit an elephant in there.

[–]disposable-assassin 4ポイント5ポイント  (0子コメント)

Funny gif but hardly educational for this reason. They're trying to use elephants as an analogue to help the audience conceive a large number but with no numbers or units, it's just a funny but nonsensical gif

[–]cg_ 2ポイント3ポイント  (1子コメント)

Each elephant represent how much fuel one elephant can burn

[–]KrAzYkArL18769 2ポイント3ポイント  (0子コメント)

(assuming an elephant can light a match and set fire to a vat of fuel)

[–]theinspiration7 0ポイント1ポイント  (0子コメント)

thanks for asking the only question I had!

[–]awhaling 0ポイント1ポイント  (1子コメント)

Yes, it says it in the description on imgur.

[–]KrAzYkArL18769 1ポイント2ポイント  (0子コメント)

Ah, I see now, after modifying the link a bit. Thanks!

[–]ravingraven 253ポイント254ポイント  (14子コメント)

Hahahaha, I like how they bleed...

[–]superdood56 38ポイント39ポイント  (7子コメント)

I like the first one that bounces off left like WEEEEEEEEE I can fly!

[–]kraken_calamari 58ポイント59ポイント  (1子コメント)

/r/nocontext

[–]FedexSentMeAHead 5ポイント6ポイント  (0子コメント)

Alright stalin

[–]minkgod 0ポイント1ポイント  (0子コメント)

ummmmmmm

[–]dr00min 0ポイント1ポイント  (0子コメント)

Planning my escape from you....

[–]LlamaJack 0ポイント1ポイント  (0子コメント)

You think they'd stay alive and while coming out of a rocket?

[–]Sumit316 45ポイント46ポイント  (13子コメント)

The Saturn V burns 4887.5L fuel per second. Density of the used fuel is about 1.2kg /L of fuel so 5865 kg/s. An average elephant weighs 4309kg so that results at 1.36 Elephants per second. (Exit velocity not accurate)

Source - 12 seconds - it is just the video version of the gif - No extra info is there

[–]freelogin 14ポイント15ポイント  (5子コメント)

The animation look like it ejects much more than 1.4 elephants/sec. So you're saying it is not accurate?

[–]soullessghost 8ポイント9ポイント  (4子コメント)

Yeah, it seems more like 10 per seconds in that video/gif.

[–]freelogin 2ポイント3ポイント  (3子コメント)

Even that surprised me. Given how heavy I thought the rocket was, I thought much more force would be needed.

[–]soullessghost 0ポイント1ポイント  (0子コメント)

That gif is about 10 seconds long, though. During this time around 100 elephants fly out of it. The mass of Saturn V was around 2, 900 tonnes. One elephant (actually depends on the species) weighs around 3 tonnes. So that would be around 300 tonnes in the first 10 seconds (10 x 10 x 3). If this was the case, then it would only take 100 seconds to completely account for the entire weight of the rocket. But according to Wikipedia, only for the first stage of launch it takes 168 seconds worth of fuel to burn (other stages add many more hundreds of seconds, but the thrust is lower).

So maybe these are baby elephants.

[–]HurbleBurble 0ポイント1ポイント  (0子コメント)

Yeah, after all, it's full of elephants.

[–]TheTardonator 0ポイント1ポイント  (0子コメント)

Force is linked to both mass and speed of ejection.

[–]augmaticdisport 5ポイント6ポイント  (0子コメント)

Came here for Elephants/second

Thanks

[–]Rubberduck_LV 1ポイント2ポイント  (2子コメント)

Wow. I'd like to see the pumps that can deliver such an amount of fuel per second.

[–]moretorquethanyou 3ポイント4ポイント  (1子コメント)

Rocketdyne F1: https://www.nasa.gov/sites/default/files/images/635083main_6413912_lg.jpg

The four largest vertical (in this picture, horizontal in real operation) are connected to the stacked fuel and oxidizer pumps.

Of course there were five F1 engines on the Saturn V so each of these pumps is only doing 1/5 of the total fuel output. Since the oxidizer and fuel pumps are about the same size, each pump is probably only handling 1/10 of the total combustion output. Ars Technica did a pretty cool piece on the engine itself not too long back.

EDIT: It looks like it was a 1:0.6 fuel:oxidizer ratio by volume or closer to a 1:0.5 by mass.

[–]AdamDaze 0ポイント1ポイント  (0子コメント)

"Only". Each pump was rated for tens of thousands of horsepower, from turbines the size of a small car engine...if i recall correctly.

[–]kornbread435 -1ポイント0ポイント  (2子コメント)

That's 1291 gallons for my fellow Americans.

[–]leshake 1ポイント2ポイント  (1子コメント)

Metric is preferred in anything scientific, even in the U.S.

[–]kornbread435 0ポイント1ポイント  (0子コメント)

Sure, but when speaking to a general population I don't see any harm in converting to gallons if some people find it easier to picture.

[–]dhyana 50ポイント51ポイント  (14子コメント)

I wanna see one with ants.

[–]7HR4SH3R 62ポイント63ポイント  (12子コメント)

I wanna see one with fuel

[–]AnindoorcatBot 78ポイント79ポイント  (10子コメント)

your lucky day

[–]7HR4SH3R 14ポイント15ポイント  (0子コメント)

That is gorgeous, thank you

[–]MrWoohoo 2ポイント3ポイント  (0子コメント)

I like this one better

[–]whinypig 1ポイント2ポイント  (4子コメント)

Where is this from? Looks very interesting.

[–]EarnMoneySitting 2ポイント3ポイント  (0子コメント)

When we left earth. It was on the discovery channel, it used to be on Netflix but I can't find it there.

[–]WatDaFok 1ポイント2ポイント  (0子コメント)

Discovery Channel - The NASA Missions : When We Left Earth (Part Two - The Explorers)

In the description

[–]CaptainObvious_1 1ポイント2ポイント  (0子コメント)

If you haven't watched this I'd recommend buying it and watching it ASAP.

[–]TheCanadianVending 0ポイント1ポイント  (0子コメント)

Here is a link to the documentary series

[–]Swift_Samurai 1ポイント2ポイント  (0子コメント)

Saturn V footage always makes me feel star-spangley. NASA is awesome.

[–]Fre5hmanJoe 0ポイント1ポイント  (0子コメント)

So that many elephants..

[–]CaptainObvious_1 0ポイント1ポイント  (0子コメント)

I think this documentary series was my favorite ever. No documentary has come as close when it comes to awe-inspiring excitement.

[–]astroNerf 1ポイント2ポイント  (0子コメント)

I like the view from camera E-8.

[–]Rokku0702 0ポイント1ポイント  (0子コメント)

What is this?! A subreddit for ANTS?!

[–]Jibbers_Crabst_IRL 12ポイント13ポイント  (2子コメント)

I smell the makings of a new KSP mod

[–]csl512 3ポイント4ポイント  (0子コメント)

Realfuels add-on.

What's the Isp?

There is the Mammoth engine. What do you get when you put elephants through a Rhino?

[–]hjklhlkj -1ポイント0ポイント  (0子コメント)

s/elepahnts/Jebediah Kerman clones/g

[–]cameronbates1 8ポイント9ポイント  (5子コメント)

Is this lbs of thrust or volume of fuel, or what?

[–]StankyMung 13ポイント14ポイント  (3子コメント)

It's gotta be weight/volume of fuel. Lbs of thrust is much more than 10 elephants a second.

[–]there_is_no_try 5ポイント6ポイント  (2子コメント)

Saturn V is 7.5 Million pounds of Thrust on the first stage.

[–]StankyMung 9ポイント10ポイント  (1子コメント)

That's 625 African elephants of thrust. Wow.

[–]there_is_no_try 2ポイント3ポイント  (0子コメント)

Correct, but note that Thrust isn't a measure per unit time, so this type of gif wouldn't illustrate it too well.

[–]Andthentherewasbacon 4ポイント5ポイント  (0子コメント)

It's in elephants

[–]FLUFYgrnBUNYman 50ポイント51ポイント  (0子コメント)

This kills the elephant.

[–]nater255 41ポイント42ポイント  (1子コメント)

Any other way to represent this would be irrelephant.

[–]shawn_v 14ポイント15ポイント  (8子コメント)

My only question is why.

[–]giggleworm 21ポイント22ポイント  (4子コメント)

To give some sort of (semi) relatable scale to the tremendous fuel consumption of these rockets.

[–]StankyMung 7ポイント8ポイント  (1子コメント)

Yeah, we all know the rocket is as tall as it is because it's full of fuel. Elephant for scale.

[–]Pregnant_Bill_Cosby 6ポイント7ポイント  (0子コメント)

It's full of elephants. Have you learned nothing?

[–]nickd182 1ポイント2ポイント  (1子コメント)

20 tons a second apparently

[–]MrWoohoo 0ポイント1ポイント  (0子コメント)

it burned 15 tons of fuel per second if I recall my crazy-for-rockets childhood correctly.

[–]Kaptain_Oblivious 6ポイント7ポイント  (0子コメント)

To show us why elephants have become endangered. Fuckin NASA

[–]ChecksUsernames 5ポイント6ポイント  (0子コメント)

I don't know but I am glad it exists

[–]flightist 0ポイント1ポイント  (0子コメント)

My only question is how many elephants per football field?

[–]abelkiller5 4ポイント5ポイント  (0子コメント)

No wonder these magnificent animals are endangered!

[–]Shnazzyone 3ポイント4ポイント  (0子コメント)

Not entirely sure what I just learned.

[–]idksomethingcreative 3ポイント4ポイント  (0子コメント)

This reminds me of back in elementary school when you forget to put the units in the end of your world problem and the teacher scolds you about it.

"The rocket burns 4887.5 what, Jimmy? Pizzas? Sodas? Elephants!?" Yes, Mrs. W, fucking elephants you obnoxious cunt.

[–]centexAwesome 2ポイント3ポイント  (3子コメント)

How do they not clog the screens?

[–]Ghost33313 1ポイント2ポイント  (2子コメント)

Also what kind of propellant are they using to launch the elephants?

[–]markenftw 2ポイント3ポイント  (0子コメント)

What an odd unit of measurement.

[–]NavinToast 4ポイント5ポイント  (0子コメント)

This is just funny to me, educational yet funny.

[–]leadchipmunk 3ポイント4ポイント  (4子コメント)

What is this supposed to be teaching?

[–]DoubleHawk4Life 1ポイント2ポイント  (2子コメント)

Either volume/mass of fuel consumption using elephants as units of measurement. I haven't worked out whether it's one or the other yet.

[–]Brinner 1ポイント2ポイント  (1子コメント)

I haven't worked it out either. Nor am I about to anytime soon.

pls report back

[–]DoubleHawk4Life 0ポイント1ポイント  (0子コメント)

Supplies are running low.

[–]Thrownitawaytho 0ポイント1ポイント  (0子コメント)

Kg/s of fuel consumption.

[–]Darkblitz9 1ポイント2ポイント  (1子コメント)

[REALISTIC]

[–]OnlyRacistOnReddit 1ポイント2ポイント  (0子コメント)

I don't know how educational this is, but it's pretty entertaining.

[–]ThePussyHammer 1ポイント2ポイント  (0子コメント)

This did absolutely nothing for me in terms of putting into perspective the amount of fuel used, but it's awesome nonetheless

[–]Erpp8 1ポイント2ポイント  (0子コメント)

To be truly accurate though, the elephants would have to be shot out at 2.58 km/s!

[–]sennacheribbo 3ポイント4ポイント  (4子コメント)

was the blood necessary?

[–]nater255 48ポイント49ポイント  (0子コメント)

Absolutely necessary. It carries oxygen to the elephants' organs.

[–]Txhighlight 3ポイント4ポイント  (2子コメント)

You go stand under a rocket and see what happens.

[–]rickscarf 1ポイント2ポイント  (1子コメント)

Wouldn't there be no blood, because it all vaporized?

[–]OnlyRacistOnReddit 1ポイント2ポイント  (0子コメント)

There wouldn't be anything left. I'm pretty sure that bones would be vaporized.

[–]jarious 0ポイント1ポイント  (0子コメント)

we should give one of this rockets to the conservationist and solve the elephants going extinct issue...

[–]mankiw 0ポイント1ポイント  (0子コメント)

Hey, what's that red stuff on the launch pa oh god

[–]crunch816 0ポイント1ポイント  (0子コメント)

Not sure if you mean weight of the fuel, elephants sacrificed, or some new horsepower-type measurement.

[–]schnoibie 0ポイント1ポイント  (0子コメント)

I thought I was in /r/dataisbeautiful ...this is awesome!

[–]witherspork 0ポイント1ポイント  (0子コメント)

Watching this is more enjoyable if you think of it as an elephant transport ship that has too much weight, so it has to dump elephants overboard to get back home.

[–]nickatnite7 0ポイント1ポイント  (0子コメント)

If they would've put less elephants in the Saturn-V, it wouldn't be as difficult to get to space.

[–]FoxSanjuro 0ポイント1ポイント  (0子コメント)

y tho

[–]knotadoc 0ポイント1ポイント  (0子コメント)

Were any elephants harmed?

[–]robschn 0ポイント1ポイント  (0子コメント)

Okay now do one with how much energy an elephant needs in terms of rockets.

[–]Weekend833 0ポイント1ポイント  (0子コメント)

Heh, actually, that seems rather efficient when I think about it - I'd imagine, at first, that it would take way more elephants to push against to get something that big to move strait up.

[–]Athrul 0ポイント1ポイント  (0子コメント)

So, what aspect of the elephants is represented there? Weight, energy value, volume?

[–]Syntrel 0ポイント1ポイント  (0子コメント)

Looks like there's some uneven thrust there.

[–]Ducky_Daniel 0ポイント1ポイント  (0子コメント)

This needs to be a ksp mod

[–]Freeiheit 0ポイント1ポイント  (0子コメント)

This would look really strange without context

[–]FluffyBunnyHugs 0ポイント1ポイント  (0子コメント)

We should switch to that fuel for all our rocket launches.

[–]dragomegakex -1ポイント0ポイント  (0子コメント)

LOL

[–]wreakinHavoK -1ポイント0ポイント  (0子コメント)

This kills the elephant

[–]MostlyRegularGuy -1ポイント0ポイント  (2子コメント)

this is absolutely of no value. incorrect exit velocity. even if exit velocity was correct... far too many elephants. :(

[–]tupper 0ポイント1ポイント  (1子コメント)

I think this is meant to illustrate propellant usage/mass rather than exit velocity.

[–]MostlyRegularGuy 0ポイント1ポイント  (0子コメント)

it illustrates both... inaccurately.

[–]turlian -1ポイント0ポイント  (0子コメント)

And here I was hoping this was a continuation of the Achievement Unlocked games.

[–]liltitus27 -1ポイント0ポイント  (0子コメント)

NEED BANANA FOR SCALE.

[–]chaunymony -1ポイント0ポイント  (0子コメント)

GOD I LOVE THE INTERNET

[–]Glassclose -1ポイント0ポイント  (0子コメント)

whoever is making this shit is doing God's work.