this post was submitted on 08 Jan 2024
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xkcd

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xkcd #2878: Supernova (imgs.xkcd.com)
submitted 10 months ago* (last edited 10 months ago) by [email protected] to c/[email protected]
 

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They're a little cagey about exactly where the crossover point lies relative to the likelihood of devastating effects on the planet.

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[–] [email protected] 58 points 10 months ago (1 children)

Wikipedia (Near-Earth Supernova) says that a 25 ly away supernova would wipe out half the ozone layer so that's probably the lower bound for what we want

[–] [email protected] 20 points 10 months ago (2 children)

Geez, how many stars do we have that close to us?

[–] [email protected] 30 points 10 months ago (2 children)

None. Space is big, and stars that can potentially supernova are rare. https://en.m.wikipedia.org/wiki/List_of_supernova_candidates

[–] [email protected] 49 points 10 months ago (1 children)

Your answer is a little misleading. I think you meant there are several stars that close to us, but none that can go supernova.

[–] [email protected] 13 points 10 months ago

That’s fair. It’s also a little misleading because there are other cosmic events that could happen that are both closer to us and potentially further away, and have in the past. I wouldn’t say we are immune from the hazards of space but my comment could have been construed that way.

[–] [email protected] 2 points 10 months ago

That's disappointing

[–] [email protected] 2 points 10 months ago* (last edited 10 months ago)
[–] [email protected] 22 points 10 months ago (1 children)

I like this one... Because I understood it!!!! Plus it's funny.

[–] [email protected] 6 points 10 months ago

When I don't understand them, I'll sometimes check out explainxkcd.com .

[–] [email protected] 15 points 10 months ago (1 children)

Pretty sure the curve should turn up on the right side at some point.

[–] [email protected] 8 points 10 months ago (4 children)

Nah, happiness should asymptotically approach 0 happiness as distance increases, due to decreased brightness. Tho, I guess there could be a discontinuity at the crossover point of where we can no longer observe it and the happiness we can extract from understanding that there are those so far away we can never see them?

[–] [email protected] 8 points 10 months ago

There's something to be said for very early supernovae. I'm sure they'd all be giddy for something beyond 13 billion light-years (or whatever that works out to in red shift).

[–] [email protected] 4 points 10 months ago

If we somehow discovered a supernova (or anything, really) beyond the observable universe, I believe the astronomers would be very very happy.

[–] [email protected] 4 points 10 months ago

At some distance, we can no longer see the stars or even the galaxy. A supernova will allow us to see in really distant past, maybe at the first generation with some really good lensing.

Think ereandel but older

[–] [email protected] 8 points 10 months ago
[–] [email protected] 3 points 10 months ago

Astronomer on a planet just a little too close: "This is a cool way to die"