5 ms·

It may already have. The question is is 725 LY far enough away that we don't blow up too?

dhosek 6y ago
Based on this https://en.wikipedia.org/wiki/Near-Earth_supernova https://en.wikipedia.org/wiki/Near-Earth_supernova it seems like we'd probably be safe, although there's not a lot of specific information about Betelgeuse so perhaps not. The global temperature increase mentioned in the first paragraph is pretty significant and added on top of the imminent anthropogenic climate change maybe don't buy green bananas for the next hundred years or so.
mrkstu 6y ago
According to this astronomy.com article, it's well outside the danger zone [0]. This [1] article discusses a closer one that may have been responsible for a mass extinction. [0] https://astronomy.com/news/2020/02/when-betelgeuse-goes-supernova-what-will-it-look-like-from-earth https://astronomy.com/news/2020/02/when-betelgeuse-goes-supe... [1] https://www.discovermagazine.com/the-sciences/a-nearby-supernova-may-have-caused-a-mass-extinction-26-million-years-ago https://www.discovermagazine.com/the-sciences/a-nearby-super...
- mehrdadn 6y ago
  Total layman here but somehow very much not-comforted by seeing it's 724 light-years away. That we might not go extinct seems like a far cry from it being safe. And I have an incredibly hard time believing Earth will be unharmed at such a seemingly astronomically small distance. Don't emitted particles travel at like thousands of miles per second? Edit: Wikipedia says < 1000 LY would have noticeable effects on life on Earth: https://en.wikipedia.org/wiki/Near-Earth_supernova https://en.wikipedia.org/wiki/Near-Earth_supernova
  - jaywalk 6y ago
    You should be comforted by the fact that there's not a damn thing we can do about it either way, so there's no point in worry about it.
    - mehrdadn 6y ago
      Is there really nothing though? Would some kind of a bunker not help? Like imagine 50m-100m underground? Not sure how much matter it might take to stop fast-moving particles (or all the dangerous forms of associated radiation).
      - databasher 6y ago
        It would not be difficult. Nuclear reactors could provide power almost indefinitely. Greenhouses could maintain plant life. Animals could be bred and slaughtered. A quick survey would have to be made of all the suitable mine sites in the country, but I shouldn't be surprised if several hundred thousand of our people could be accommodated. Every nation would undoubtedly follow suit.
      - _ph_ 6y ago
        There is no risk for the Earth due to Betelgeuse. At worst, space travel will be impacted, but we would have 100k years to prepare for that after it blows up.
      - samus 6y ago
        Given a high enough tech level and a sufficient handle on the associated ethics, you could [digitize your population and restore it afterwards](http://localroger.com/revelation-passage/borden3.html http://localroger.com/revelation-passage/borden3.html)
  - nwallin 6y ago
    There's a world of difference between "we will notice it" and "we have to be worried about it". Betelgeuse will explode in a faint Type II-P supernova, which is the least dangerous type. The thing to really be worried about with supernova are gamma ray bursts, which require low metallicity stars of at least 120 solar masses. Betelgeuse is a high metallicity star with about 15 solar masses. So it's nowhere even in the ballpark of producing a gamma ray burst. Look at this graph: https://upload.wikimedia.org/wikipedia/commons/5/5a/Comparative_hypernova_light_curves.png https://upload.wikimedia.org/wikipedia/commons/5/5a/Comparat... Betelgeuse will be the blue line that peaks the lowest and plateaus out. (the P is Type II-P stands for "plateau") This is a logarithmic plot, so the brightest supernova are like 40 times as bright as Betelgeuse's supernova will be. Furthermore, this is just visual light; in terms of gamma rays, while normal supernova are bright in gamma rays, gamma ray bursts are many orders of magnitude brighter. When Betelgeuse goes supernova, no species will go extinct, no crops will fail, no uptick in cancer will happen. It might dork up some migration patterns and mess with particularly precarious food chains, but the effects will be minor, especially compared to the catastrophic damage humanity is doing to the environment.
    - mehrdadn 6y ago
      > There's a world of difference between "we will notice it" and "we have to be worried about it". The phrase I was referring to was "have noticeable effects on Earth's biosphere", not "we will notice it". The article explains: Historically, each near-Earth supernova explosion has been associated with a global warming of around 3–4 °C (5–7 °F). An estimated 20 supernova explosions have happened within 300 pc of the Earth over the last 11 million years. Type II supernova explosions are expected to occur in active star-forming regions, with 12 such OB associations being located within 650 pc of the Earth. At present, there are six near-Earth supernova candidates within 300 pc. That seems like quite a bit more just seeing something in the sky or seeing a few species get their migration patterns messed up. And re: gamma ray bursts, I do agree they would be bad if they occurred, but you might notice I didn't mention them either. My first worry was about fast-moving particles, which you didn't mention anything about. Why would those not be problematic? You might very well be right about Betelgeuse specifically, but I'm guessing you're relying on more information because I just can't deduce it from the information I'm seeing.
grey-area 6y ago
Oh no it hasn't, not in our frame of reference.

Based on this https://en.wikipedia.org/wiki/Near-Earth_supernova https://en.wikipedia.org/wiki/Near-Earth_supernova it seems like we'd probably be safe, although there's not a lot of specific information about Betelgeuse so perhaps not. The global temperature increase mentioned in the first paragraph is pretty significant and added on top of the imminent anthropogenic climate change maybe don't buy green bananas for the next hundred years or so.

mrkstu 6y ago

According to this astronomy.com article, it's well outside the danger zone [0]. This [1] article discusses a closer one that may have been responsible for a mass extinction. [0] https://astronomy.com/news/2020/02/when-betelgeuse-goes-supernova-what-will-it-look-like-from-earth https://astronomy.com/news/2020/02/when-betelgeuse-goes-supe... [1] https://www.discovermagazine.com/the-sciences/a-nearby-supernova-may-have-caused-a-mass-extinction-26-million-years-ago https://www.discovermagazine.com/the-sciences/a-nearby-super...

mehrdadn 6y ago
Total layman here but somehow very much not-comforted by seeing it's 724 light-years away. That we might not go extinct seems like a far cry from it being safe. And I have an incredibly hard time believing Earth will be unharmed at such a seemingly astronomically small distance. Don't emitted particles travel at like thousands of miles per second? Edit: Wikipedia says < 1000 LY would have noticeable effects on life on Earth: https://en.wikipedia.org/wiki/Near-Earth_supernova https://en.wikipedia.org/wiki/Near-Earth_supernova
- jaywalk 6y ago
  You should be comforted by the fact that there's not a damn thing we can do about it either way, so there's no point in worry about it.
  - mehrdadn 6y ago
    Is there really nothing though? Would some kind of a bunker not help? Like imagine 50m-100m underground? Not sure how much matter it might take to stop fast-moving particles (or all the dangerous forms of associated radiation).
    - databasher 6y ago
      It would not be difficult. Nuclear reactors could provide power almost indefinitely. Greenhouses could maintain plant life. Animals could be bred and slaughtered. A quick survey would have to be made of all the suitable mine sites in the country, but I shouldn't be surprised if several hundred thousand of our people could be accommodated. Every nation would undoubtedly follow suit.
    - _ph_ 6y ago
      There is no risk for the Earth due to Betelgeuse. At worst, space travel will be impacted, but we would have 100k years to prepare for that after it blows up.
    - samus 6y ago
      Given a high enough tech level and a sufficient handle on the associated ethics, you could [digitize your population and restore it afterwards](http://localroger.com/revelation-passage/borden3.html http://localroger.com/revelation-passage/borden3.html)
- nwallin 6y ago
  There's a world of difference between "we will notice it" and "we have to be worried about it". Betelgeuse will explode in a faint Type II-P supernova, which is the least dangerous type. The thing to really be worried about with supernova are gamma ray bursts, which require low metallicity stars of at least 120 solar masses. Betelgeuse is a high metallicity star with about 15 solar masses. So it's nowhere even in the ballpark of producing a gamma ray burst. Look at this graph: https://upload.wikimedia.org/wikipedia/commons/5/5a/Comparative_hypernova_light_curves.png https://upload.wikimedia.org/wikipedia/commons/5/5a/Comparat... Betelgeuse will be the blue line that peaks the lowest and plateaus out. (the P is Type II-P stands for "plateau") This is a logarithmic plot, so the brightest supernova are like 40 times as bright as Betelgeuse's supernova will be. Furthermore, this is just visual light; in terms of gamma rays, while normal supernova are bright in gamma rays, gamma ray bursts are many orders of magnitude brighter. When Betelgeuse goes supernova, no species will go extinct, no crops will fail, no uptick in cancer will happen. It might dork up some migration patterns and mess with particularly precarious food chains, but the effects will be minor, especially compared to the catastrophic damage humanity is doing to the environment.
  - mehrdadn 6y ago
    > There's a world of difference between "we will notice it" and "we have to be worried about it". The phrase I was referring to was "have noticeable effects on Earth's biosphere", not "we will notice it". The article explains: Historically, each near-Earth supernova explosion has been associated with a global warming of around 3–4 °C (5–7 °F). An estimated 20 supernova explosions have happened within 300 pc of the Earth over the last 11 million years. Type II supernova explosions are expected to occur in active star-forming regions, with 12 such OB associations being located within 650 pc of the Earth. At present, there are six near-Earth supernova candidates within 300 pc. That seems like quite a bit more just seeing something in the sky or seeing a few species get their migration patterns messed up. And re: gamma ray bursts, I do agree they would be bad if they occurred, but you might notice I didn't mention them either. My first worry was about fast-moving particles, which you didn't mention anything about. Why would those not be problematic? You might very well be right about Betelgeuse specifically, but I'm guessing you're relying on more information because I just can't deduce it from the information I'm seeing.

grey-area 6y ago

Oh no it hasn't, not in our frame of reference.