My experience is that Slack worked great last winter, when the broadband satellite was up. When it's down, folks use an IRC-style client to cope with the very limited & expensive bandwidth from Iridium.
Pole doesn't have Starlink. McMurdo does. There are reasons.
Polar coverage from GEO satellites is limited because how close to the horizon GEO satellites are from Pole. Pole uses old GEO satellites which are low on fuel and have relatively large inclinations... then you can talk to them for ~ 6 hours per 24.
NB: based on some quick searches, it seems that low-metalicity Pop III stars would rely on the pp (proton-proton) fusion chain. That's going to slow reaction somewhat, and extend lifetime. But for high-mass stars with only a few millions of years expected lifetime in a Pop I/II class, that's ... still a relatively modest difference compared to the several hundred million year lifespan of the early Universe.
Another interesting quirk of Pop III stars is that their initial mass function is expected to form much more massive stars than Pop II or Pop I. So even if Pop III stars are longer lived at the same mass as Pop II or Pop I, there will be a lot more supernovae per time, leading to fast enrichment and then Pop II.
The word "generation" isn't really a thing in astronomy jargon. "Population III" is a population, and it includes stars formed after some supernovae, up to the point where the metals % gets high enough to be Population II.
There's an endless supply of organic, free range cosmic rays that rain down from the sky. They've been scientifically useful in many ways, not just this one.
