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How many supernova explode every year?

badastronomy.beehiiv.com

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Re: How many supernova explode every year?

#71

Post by 8fingerlouie »

rbanffy wrote: post #42
frainfreeze wrote: post #39

Earlier quoted context omitted.

Does it need fixing?

Since I'd like to live forever, then yes.

Technically you can live forever in a universe that is completely empty, it'll just be a lot of cold dark nothing for eternity.

Living forever is such a strange desire, considering that complex life has existed on earth for just a fraction of the time it has existed, and humanity even less than that. I recommend watching the Kurtzgesagt video called All of History in one hour (https://www.youtube.com/watch?v=S7TUe5w6RHo&t=3670s). It displays all of earths history in one hour, and humanity is merely a few seconds of it.

Earth is ~4.5 billion years old, that's 4500000000 years, and in 1300000000 years it will be uninhabitable by humans, and in another 4.5 billion years (roughly 3.2 billion years after becoming uninhabitable) it will be engulfed by the sun.

Assuming humanity manages interstellar space flight you could possibly escape earth and live somewhere else until that also dies, but in case it is not practical or possible, you get to enjoy 3.2 billion years of literally choking and being burned alive on earth.

Assuming you did escape earth (or you're immortal so escaping doesn't matter) In 1000000000000 years the last star will be born, and in 100000000000000 years the last star will die out.

You now have an extremely long time to enjoy suffocating in hard vacuum with your body being boiled by the low pressure, and all in complete darkness until the heat death of the universe occurs in roughly 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 years

Re: How many supernova explode every year?

#73

Post by IggleSniggle »

IggleSniggle wrote: post #65
whoisthemachine wrote: post #58

Earlier quoted context omitted.

Maybe they will have to transition from Base 26 counting to Base 64!

It's in the article. SN2067aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa vs SN2067aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa. Apparently astronomers find base26 very straightforward and reasonable!

Also, as a cousin comment alludes to, for there to be one of the above supernovae, there will also be a supernova named SN2067iamsoverystupidoopssorry and a SN2067thisnamingschemawasabadidea

Re: How many supernova explode every year?

#74

Post by ben_w »

Hmm…

So that's cool, but now I'm thinking: the distant galaxies are redshifted and time-dilated in equal proportion, and also more densly packed because the universe was smaller in the past, so I expect the actual rate of supernovas to be significantly smaller than simply multiplying 1/century/galaxy by 1e11 galaxies.

Edit: also I don't know if rate of supernovas changes over history thanks to different steller environments giving the population-1/2/3 generations of stars…

Re: How many supernova explode every year?

#75

Post by the_af »

8fingerlouie wrote: post #71
rbanffy wrote: post #42

Earlier quoted context omitted.

Since I'd like to live forever, then yes.

Technically you can live forever in a universe that is completely empty, it'll just be a lot of cold dark nothing for eternity. Living forever is such a strange desire, considering that complex life has existed on earth for just a fraction of the time it has existed, and humanity even less than that. I recommend watching the Kurtzgesagt video called All of History in one hour ( https://www.youtube.com/watch?v=S7TUe5w…

The Cosmos (both Sagan and Tyson's) shows also display the tiny fraction of life in the history of the universe with their "Cosmic Calendar".

Re: How many supernova explode every year?

#78

Post by Voultapher »

IggleSniggle wrote: post #65
whoisthemachine wrote: post #58

Earlier quoted context omitted.

Maybe they will have to transition from Base 26 counting to Base 64!

It's in the article. SN2067aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa vs SN2067aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa. Apparently astronomers find base26 very straightforward and reasonable!

As per the post:

> That’s one hundred billion supernovae per century, or a billion per year, or about 30 per second.

7 characters of base26 gives you 8 billion combinations. "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" requires ~1e48 events when going by the actual non base26 scheme. So I wouldn't be worried.

Re: How many supernova explode every year?

#79

Post by aqme28 »

delusional wrote: post #51
RicoElectrico wrote: post #41

Earlier quoted context omitted.

[flagged]

HUGE SPOILER ALERT. SERIOUSLY, PLAY OUTER WILDS. It's a little more than just " the sun will also go supernova". The core conceit of the games story is that you're living in the final moments of dying universe.

The fact that there is a supernova isn't much of a spoiler. It's more like the premise of the game. It's difficult to not discover this within the first 30 minutes.

Re: How many supernova explode every year?

#80

Post by andyjohnson0 »

dostick wrote: post #52
herendin2 wrote: post #18

If I got the math right, then about 1 in every 32,000 stars in the universe goes supernova each year. That's scary. But I think I'm getting the math very wrong. edit: I guess my error might be related to confusing a probability factor with the number of incidents in a period. edit: The right answer is probably up to 1 in every 10bn stars go supernovae in the universe each year (or 1 in 10bn die and a fraction are sup…

Isn’t the answer infinity? We don’t know what’s beyond observed part of universe, and there’s infinity number of universes. If our emerged then there’s others.

> and there’s infinity number of universes

There is no evidence that there are a infinite number of universes. All we know of is the one we exist in. The many worlds interpretation of quantum mechanics posits that there are a very large number of non-interacting "worlds" which may or may not be the same as "universes".

And if you meant "infinity number of galaxies" then that would require an infinite-size universe, and we don't know if that is the case for our universe. It could be, or it could be finite but unbounded.

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