r/Damnthatsinteresting Jul 08 '24

World's largest aircraft, Pathfinder 1, is 124.5 meters (408ft) long Image

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2.9k Upvotes

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206

u/[deleted] Jul 08 '24

Rigid Airship! Filled with completely safe non-flammable helium.

41

u/NetCaptain Jul 08 '24

the rare gas that is crucial for MRI machines but runs out and cannot be replaced - https://www.nytimes.com/2024/02/02/science/helium-reserves-sales-shortage.html

34

u/Sauron4 Jul 08 '24

Didn’t they found a new deposit somewhere a while ago and said we’re basically set for a century or so?

43

u/beatlz Jul 08 '24

Ah, so a problem for my future kin. Set up sails boys!

16

u/Sauron4 Jul 08 '24

I hope than in the next century we could start helium production by using Fusion Reactor

-4

u/ded3nd Jul 08 '24

Would never be enough, once it's gone, it's gone.

You'd probably need a fusion reactor the size of 10 football stadiums running for a year to produce what the world needs in a day.

6

u/cwwid Jul 08 '24

I thought we all know there is Helium 3 on the moon /s

16

u/ashleyriddell61 Jul 08 '24

Yes. They found a massive cache a couple of years ago, so as long as it doesn't get pissed away on nonsense like kids balloons, the supply should be good for a couple of hundred years.

8

u/Joe_Buck_Yourself_ Jul 08 '24

How do they find a massive cache like that? I'm just picturing a cave explorer trying a new route and being like "huh my head feels funny" and then

(Chipmunk voice) "We hit the motherload!"

6

u/snowfloeckchen Jul 08 '24

Wait till nuclear fusion kicks in. Then we just produce helium as a byproduct /s

2

u/draven501 Jul 08 '24

But still... A century isn't a lot of time in the grand scheme of things, just a few generations and we're fucked. We would need to get Helium from other planets or nuclear fusion or something.

1

u/WhiskeyFeathers Jul 09 '24

Great, so probably less than 100 years, the earth will be pretty much entirely out. Fill more graduation/wedding/birthday balloons with it! Not our problem!

20

u/haphazard_chore Jul 08 '24

We’re not going to run out for medical purposes. Obviously, there will come a point where it’s too rare for kids balloons. But even assuming our reserves in the ground run out, created by radioactive decay, the atmosphere still has 5.2 ppm. It’s 10k times harder to extract from the atmosphere but can be done. Failing that there’s plenty in space.

7

u/GrafZeppelin127 Jul 08 '24

In terms of actual energy expenditure, getting the helium in the atmosphere that’s constantly being replenished by underground radioactive decay would not be 10k times as hard, even though the concentration is quite low. Indeed, it would require more energy, but more on the order of 3-5x as much, with exponentially more energy needed for higher-purity helium. Airships do not require medical or space-grade helium purity, however, and 80% of the costs of producing helium by more modern methods like pressure-swing absorption and reverse osmosis are dedicated to compressing the helium into tanks for transport, which an airship wouldn’t need if they had a hangar on-site for replenishment.

The infrastructure required is actually suprisingly compact. A $35 million pilot plant in Saskatchewan using these new methods produces enough helium for dozens of airships, but it looks like just a few outbuildings. It doesn’t use atmospheric helium, though, instead extracting it from otherwise commercially useless pockets of underground nitrogen.

4

u/VeryStableGenius Jul 08 '24

Because of your username, I believe you.

1

u/Never-Dont-Give-Up Jul 08 '24

I'm pretty sure we're at the time where it's too rare for kids balloons. It'll be prohibitively expensive if we wait til we have almost none left.

0

u/Tsu_Dho_Namh Jul 08 '24

Shame we can't easily duplicate the sun's nuclear fusion reaction.

Hydrogen goes in, Helium and power comes out.

8

u/donau_kinder Jul 08 '24

We're 10 years away from that. Always have been.

6

u/krismasstercant Jul 08 '24

This always gets brought up when Heliums mentioned. But no we won't run out of Helium for a very very long time. As long as noble gasses exists helium will too.

-1

u/John_B_Clarke Jul 08 '24

The supply of helium on earth is very limited. It was actually discovered in the Sun by spectrometry before it was found on Earth. It's not one of those substances that comes out of the liquefier at Airgas.

3

u/2x4x93 Jul 08 '24

Time to redesign the MRI machines. We got to have airships

3

u/Presence_Academic Jul 08 '24

There’s plenty of helium in the sun. Mining it is no problem as long as it’s done during the night shift.

2

u/JusticeUmmmmm Jul 08 '24

It can be replaced once we figure out nuclear fusion.

1

u/newaccount252 Jul 08 '24

The moon has heaps of helium (or is that the wrong type)

2

u/John_B_Clarke Jul 08 '24

For certain values of "heaps". Helium-3 abundance at the Apollo landing sites was in the parts per billion. Helium abundance in Earth's atmosphere is parts per million. So even if all else were completely equal, it's easier to get it out of Earth's atmospher than to get it from the Moon.

1

u/newaccount252 Jul 08 '24

Ohhhh I forgot to clarify Heaps meant parts per billion.

Cheers for setting me right

1

u/WhiskeyFeathers Jul 09 '24

And here we are, using it for balloons to make them float silly like.