<10% of natural gas plants recover helium. All of them extract it. The remaining >90% vent it into the atmosphere. This is an engineering / money problem, not a physics problem.

It becomes a larger problem as the world moves away from fossil fuels like natural gas.

I'm not a chemist but are there really no alternatives? Running fusion plants to make helium seems very unlikely to become cost effective, but it would be quite the sci-fi future if we filled party balloons by bombarding hydrogen with free protons.

I guess there aren't any easy molecules to break apart to get helium either since its a noble gas. No hydrolyses type solutions because there aren't any molecules that incorporate helium. I guess radioactive decay, but even that is ultimately limited over long enough timescales.

There are NO alternatives. There's nothing else that stays liquid at 4 K and absolutely nothing else comes close.

> it would be quite the sci-fi future if we filled party balloons by bombarding hydrogen

How dangerous are party balloons filled with hydrogen? Not a whole balloon arch obviously.

I had a science teacher that did this in class, then taped a match on the end of a yardstick and held it under the balloon. They made quite a bang. I wouldn't want to be right next to it when it went off.

Was there an experimental control?

How does that bang compare to the bang from an equally-inflated balloon full of ordinary air?

We did this. One balloon with plain air. One with pure hydrogen. One with 50/50 hydrogen and air. The one with pure hydrogen popped closer in magnitude to the pure air than it was to the 50/50 mix.

As a kid I took a lot of classes at the Lawrence Hall of Science in Berkeley, which was paradise for fledgling nerds. On the last day they would have a little closing ceremony with some cute little science experiment. One of my favorites was "Going Out With A Bang".

The instructors would bring out a helium balloon and a candle on a meter stick. The balloon goes pop, huzzah.

Then the twist. "Hey, wanna do it again?" All the kids would be like "meh, I guess?" They would then bring out a balloon full of hydrogen (maybe some oxygen too?). It would look identical to the first one, floating there tethered to the lab bench.

When the candle hit the second one, it made a white flash and a really sharp BANG. It was an order of magnitude louder, and you could hear the transient bouncing off the walls and echoing in the halls. It made an impression.

Yeah I've seen that demonstration in school too. But if the teacher was willing to do it in school, with kids, how dangerous was it really?

Along with the other commenter, I'll add that a classroom is usually a lot bigger than a home dining room or other domestic party locations. That size also helps things dissipate instead of reflect. Not sure by how much but I'm sure it does something.

My chemistry teacher told us how once when he ignited helium in a test tube, the tube broke and he ended up with pieces of glass embedded in his skin. The students had face masks and he was looking the other way "just in case" for this "safe" experiment but he could have easily been blinded.

Things can always go wrong. We probably shouldn't strive for 100% safety because they we'd spend our lives in a padded cell. But we also shouldn't assume things are safe because they're common or routine.

You can get permanent hearing damage from that demonstration if you stand right next to that balloon.

Makes sense.

> It becomes a larger problem as the world moves away from fossil fuels like natural gas.

I actually remember a similar problem from some compound that was mainly formed as a byproduct of some old Canadian nuclear reactor design. As the tech gets phased out, the material is no longer available in significant quantities, with consequences for a projects that need it (like Iter).

Some things can be cheap if they are produced as a byproduct, but very expensive if they have to be obtained directly.

As usual - 'there is scarcity of XYZ' -> price it accordingly, and markets will align quickly. Dont expecr private companies to have long term thinking, thats not how bonuses for those steering the wheel are set up.