[HN Gopher] JWST Captures Image of Supernova That 'Absolutely Sh...
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       JWST Captures Image of Supernova That 'Absolutely Shattered' a Star
        
       Author : Brajeshwar
       Score  : 110 points
       Date   : 2023-12-14 16:19 UTC (6 hours ago)
        
 (HTM) web link (www.smithsonianmag.com)
 (TXT) w3m dump (www.smithsonianmag.com)
        
       | squigz wrote:
       | Isn't that what every supernova does?
        
         | djbusby wrote:
         | And it's super awesome every time!
        
         | jsbisviewtiful wrote:
         | "Shattered" seems like an odd way of describing it but at some
         | level... sure.
        
           | JumpCrisscross wrote:
           | > _"Shattered" seems like an odd way of describing it_
           | 
           | Would love for an astrophysicist to pine in. But my
           | understanding is supernovae are usually balanced enough to
           | squeeze their stars' cores. This appears to have been
           | unbalanced such that the core was "broken" instead of
           | uniformly compressed.
        
         | zethus wrote:
         | Some stars survive supernovae, and are known as zombie stars
         | [1]. One believed example is SN2012Z [2]
         | 
         | [1] https://en.wikipedia.org/wiki/Zombie_star
         | 
         | [2]
         | https://iopscience.iop.org/article/10.3847/1538-4357/ac3bbd/...
        
           | squigz wrote:
           | Neat! Thanks for sharing! Space is crazy :)
        
           | falcrist wrote:
           | Here I was thinking "zombie star" was another term for ANY
           | stellar remnant like a white dwarf or neutron star.
        
         | hinkley wrote:
         | I thought, surely they mean a supernova obliterated a companion
         | star, but you're right. They're talking about the exploding
         | star.
         | 
         | Is this noteworthy because we've seen it, rather than that it
         | exists? How many novae cores have we imaged before?
        
         | chasil wrote:
         | Type 1A supernovas are completely destroyed in the process of
         | their explosions.
         | 
         | The others usually retain their core, either as a neutron star
         | or the final collapse to a black hole.
        
       | mensetmanusman wrote:
       | It's kind of fun to think that at any moment something might pop
       | and our entire solar system would disappear in a blink of an eye.
        
         | lostapathy wrote:
         | Our sun isn't massive enough to ever go supernova.
        
           | TheEzEzz wrote:
           | Supernova are powerful enough that even a star in a different
           | solar system going nova can kill you, if it's a "nearby"
           | system. But I believe there aren't any stars close enough
           | that would go supernova any time soon.
        
             | rnk wrote:
             | It's always the one you don't expect that gets you.
        
             | jsbisviewtiful wrote:
             | A good premise for a sci-fi series: In the distant future,
             | a large fleet of earth's best and brightest travels the
             | stars while desperately trying to invent Earth's last
             | ditch-effort to save its 12 billion inhabitants from a
             | soon-to-be cataclysmic, near-earth supernovae: FTL travel.
             | After decades of progress finally nears fruition, the fleet
             | permanently loses contact with earth; humanity's home Solar
             | System's remnants lost to the beautiful, nightmare... The
             | fleet of 80,000 now works to save itself, the last of
             | humanity.
        
           | ceejayoz wrote:
           | https://en.wikipedia.org/wiki/Near-Earth_supernova
           | 
           | It wouldn't wipe out the solar system, but might have harmful
           | impacts on our biosphere.
        
         | strictnein wrote:
         | Reporting from two hours in the future (relatively): hasn't
         | happened yet.
        
         | robotresearcher wrote:
         | If the sun went pop, the Earth wouldn't notice for more than
         | eight minutes, and Neptune not for 4 hours.
        
           | quickthrower2 wrote:
           | If the cause of the pop is moving at the speed of light too.
           | But if it wasn't we might get an early warning.
        
       | cosmotic wrote:
       | Links to the full res images (under Download Options):
       | https://webbtelescope.org/contents/media/images/2023/149/01H...
        
         | amelius wrote:
         | Where can I download the time-lapse video?
        
           | omgJustTest wrote:
           | It's streaming live right now!
        
             | AlecSchueler wrote:
             | Where!?
        
       | ltbarcly3 wrote:
       | Right, big explosion, easier to see. Typical solar toxicity. I
       | can't wait for it to detect a gentle supernova, gently whisping a
       | luliby to its exoplanets.
        
       | strictnein wrote:
       | Was wondering what the width of the image we're seeing is, so I
       | did some quick googling:
       | 
       | > The expanding cloud of material left over from the supernova
       | now appears approximately 10 light-years (3 pc) across from
       | Earth's perspective
       | 
       | https://en.wikipedia.org/wiki/Cassiopeia_A
        
       | MKais wrote:
       | > Chandra's study revealed the amounts of different elements
       | produced by the explosion. The supernova has spat out 10,000
       | times the mass of the Earth in sulfur, 20,000 times Earth's mass
       | in silicon, 70,000 Earth masses of iron and a million Earth
       | masses of oxygen.
       | 
       | Mind went supernova
        
       | JohannesH wrote:
       | Wow it is absolutely fascinating and awe-inspiring. Anybody know
       | what the blob (looks like wavy gold foil) in the bottom right of
       | the picture is?
        
         | JohannesH wrote:
         | Should have read the description.
         | 
         | > There are also several light echoes visible in this image,
         | most notably in the bottom right corner. This is where light
         | from the star's long-ago explosion has reached, and is warming
         | distant dust, which is glowing as it cools down.
        
       | humble_ant wrote:
       | Fair to say this happened 11,000 years ago?
        
         | AlecSchueler wrote:
         | Equally fair to say it's happening right now depending on your
         | frame of reference.
        
       | shortrounddev2 wrote:
       | I'm looking at older pics of Cassiopeia A from the Hubble
       | telescope, and it looks substantially different. How much time
       | needs to pass before a supernova is visibly different? My
       | instinct was that something like this would change over thousands
       | of millions of years, but I'm guessing that's wrong
        
       | crtified wrote:
       | How quickly do the (damaging to nearby solar systems etc) effects
       | of a supernova propagate through space, in relation to the speed
       | of light?
       | 
       | Or, to put it another way, could we detect the damaging effects
       | of a nearby supernova expanding towards us _before_ those effects
       | actually hit us? And if so, by what factor?
        
         | Scaevolus wrote:
         | The radiation propagates at light speed, but the harmless
         | neutrinos reach us a few hours before the potentially dangerous
         | X-rays and gamma rays. A supernova would have to be within
         | roughly 160 light years to be damaging to Earth.
         | 
         | https://news.fnal.gov/2019/03/waiting-for-neutrinos/
         | 
         | https://earthsky.org/astronomy-essentials/safe-distance-from...
        
       | deskamess wrote:
       | > The star collapses in an explosion
       | 
       | Can anyone explain the above phrase?
        
         | its_ethan wrote:
         | This might be helpful:
         | https://en.wikipedia.org/wiki/Supernova#Core_collapse
         | 
         | I'm not an expert, but an analogy here could perhaps be if you
         | drop a cup of water on the floor (assuming it doesn't break)
         | some of that water is going to rebound on itself/the cup, and
         | will splash upwards. That would be gravitational potential
         | energy being converted to kinetic energy, causing material to
         | be ejected.
         | 
         | With stars, there is a TON of gravitational potential energy,
         | and so when it's converted to kinetic energy during a collapse,
         | you "explode" the lighter weight outer layers of the star away
         | from the more dense core. Some of the stars core remains, and
         | can become either a neutron star or a black hole.
        
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       (page generated 2023-12-14 23:00 UTC)