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[Simmura McCrea]

Teacher: "We cant see far off stars because the light isnt bright enough to reach us... Yes (myname)?"
"Isnt that just because the further stars are away from us the faster they move away from us and the faster they move away from us the redder the become, eventually turning infrared and leaving the visible spectrum?"

Thank you minutephysics!

*minutephysics five*

[Nadaka]

Teacher: "We cant see far off stars because the light isnt bright enough to reach us... Yes (myname)?"
"Isnt that just because the further stars are away from us the faster they move away from us and the faster they move away from us the redder the become, eventually turning infrared and leaving the visible spectrum?"

Thank you minutephysics!

That isn't correct though. Yes, stars found in distant galaxies are red shifted, but that isn't why they are not visible. Stars are essentially black body radiation sources modified modestly by a few emission and absorption spectra. That means they emit "light" on a very wide range of spectra. For every bit of a stars spectra that is shifted out of the visible range and into infrared, another bit of ultraviolet spectrum is shifted into the visible.

Stars become "invisible" because they they are effectively point sources of energy and the amount of energy hitting a given receiver from a distant point source is the square root of the distance minus any energy absorbed by the not quite vacuum of space, and that distance is very very large.

[miauw62]

Teacher: "We cant see far off stars because the light isnt bright enough to reach us... Yes (myname)?"
"Isnt that just because the further stars are away from us the faster they move away from us and the faster they move away from us the redder the become, eventually turning infrared and leaving the visible spectrum?"

Thank you minutephysics!

That isn't correct though. Yes, stars found in distant galaxies are red shifted, but that isn't why they are not visible. Stars are essentially black body radiation sources modified modestly by a few emission and absorption spectra. That means they emit "light" on a very wide range of spectra. For every bit of a stars spectra that is shifted out of the visible range and into infrared, another bit of ultraviolet spectrum is shifted into the visible.

Stars become "invisible" because they they are effectively point sources of energy and the amount of energy hitting a given receiver from a distant point source is the square root of the distance minus any energy absorbed by the not quite vacuum of space, and that distance is very very large.

The more you know. I'll remember that.

[Levi]

I thought they were invisible because the alien civilizations that live there have launched an invading force towards earth, and because its a straight line the alien fleet blocks out all the light from the star behind it? 

[Simmura McCrea]

I thought they were invisible because the alien civilizations that live there have launched an invading force towards earth, and because its a straight line the alien fleet blocks out all the light from the star behind it?

Shit, he's onto us! Abduct him!

[Hanslanda]

I thought they were invisible because the alien civilizations that live there have launched an invading force towards earth, and because its a straight line the alien fleet blocks out all the light from the star behind it?

Shit, he's onto us! Abduct him!

Bro, we're like four hundred billion lightyears away.

[Levi]

I thought they were invisible because the alien civilizations that live there have launched an invading force towards earth, and because its a straight line the alien fleet blocks out all the light from the star behind it?

Shit, he's onto us! Abduct him!

Bro, we're like four hundred billion lightyears away.

They could have sent the sleeper agents first.   

[Hanslanda]

The sleeper agents... Well, they're asleep. We didn't think we'd need them for another four hundred years. Even as fast as our warp drives go, we've still got a long journey ahead.

[kaenneth]

Nadaka only knows that because he's a Starspawn kitten.

[Hanslanda]

This would explain the creepy tentacles.

[Nadaka]

Ia Ia meow ftagn.

[Descan]

I want cuddles.

[kaijyuu]

Me too.

[Simmura McCrea]

* Simmura McCrea cuddles up with Descan and Kai on a sofa with some chocolate.

[RedKing]

Me three. And I even had them not too long ago.