Significance of Sanctuary's Green Sun

[Atarlost]

I know Iron and Boron can burn green under the right conditions.

All old stars have iron. They aren't green. Enough iron to burn green would kill fusion and nothing would be burning.

I think Boron is a reaction poison. I know it is for fission and both fusion and fission involve neutron chain reactions. Again, enough to burn green would probably kill the fusion reaction.

[Drako Slyith]

That's true. Still, I would love to see a solid iron star No light, no radiation, just solid iron with a molten iron core! Ohhhh... Shiny....

[Aury]

That wouldn't be a star though; stars by definition undergo hydrogen fusion.

[Drako Slyith]

I know, but still, a huge iron, planet, I guess with other planets orbiting it.

[Atarlost]

Iron isn't green when not burning. It's black or grey or if oxidized reddish. This is such common knowledge it's...

This is ridiculous. There's a word for a star sized chunk of iron. It's called a black dwarf. It would be referred to not as a green sun but as <drumroll /> a black dwarf. If it were still glowing from residual hydrogen fusing on the surface it would be a white dwarf.

[Aury]

He wasn't even talking about the Green Sun anymore, he was just saying he wanted to see a black dwarf in-game, as a tangental side-conversation.

[Ttech]

He wasn't even talking about the Green Sun anymore, he was just saying he wanted to see a black dwarf in-game, as a tangental side-conversation.

All things considered, wouldn't it be a brown dwarf?

[Aury]

No, a brown dwarf has some kind of lithium reaction IIRC that putters out very slowly over time - its not a full on star because it doesn't fuse hydrogen, nor will it puff up at the end of its life, like a star will do; it just cools down. A black dwarf wouldn't have any reaction, its just a massive ball of solid mass on the lower end of the stellar spectrum, generally long-cooled white dwarfs that have radiated all their energy away.

[Kerebron]

There are no stars that look green. In fact our Sun has a peak in its spectrum in green wavelength. But there are green objects in space - mostly emission nebulas.

[Ttech]

No, a brown dwarf has some kind of lithium reaction IIRC that putters out very slowly over time - its not a full on star because it doesn't fuse hydrogen, nor will it puff up at the end of its life, like a star will do; it just cools down. A black dwarf wouldn't have any reaction, its just a massive ball of solid mass on the lower end of the stellar spectrum, generally long-cooled white dwarfs that have radiated all their energy away.

So basically a lump of cheese that is a few trillion years old. I've never heard it referred to as a black dwarf but heck - it works.

[Lokasenna]

The intergalactic version of Greenpeace is dumping something on it that burns green to protest the rampant use of Auto Mining Devices and carbon emissions from NAMI Launchers.

[stealthx]

So according to the Book of Tales, the Sisters extract, Sanctuary has... a Green Sun.

I knew it! The sisters were on drugs !

[digdug]

There are no stars that look green. In fact our Sun has a peak in its spectrum in green wavelength. But there are green objects in space - mostly emission nebulas.

Kerebron is right

Color is a perception we humans have because of the kinds of pigments used in our retinae. Our eyes do not sense light evenly across the visible spectrum but have a greater sensitivity for green light, and somewhat less so for red and blue light as the response spectrum below illustrates.

All A-type stars actually have a spectrum that would make them green but they appear white to human eyes.

So, there are no genuinely green stars because stars with the expected temperature emit their light in a way that our eye combines into the perception of 'whiteness'.

[Aury]

Yeah, but the sisters are humans, not neohumans or pteravores or digital metropolis citizens. They would perceive it is white, not green.

[Drako Slyith]

Maybe they had green glass on their windows?