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Imagine being alive when it goes supernova (relatively to us on earth). That would be a spectacular thing to witness.

by me_me_me 7y ago

mongol 7y ago
I am sure it will be cloudy where I am.
- ceejayoz 7y ago
  Betelgeuse would be visible for weeks, and be at its brightest point (as bright as the full moon) for several days.
- sixstringtheory 7y ago
  Even if you live in the tropics and it’s during the rainy season, you still have a good chance of seeing one. It’s not like a solar eclipse where you have very short time period to view it, it could last weeks to years (of course the peak would be shorter, but probably still on the order of days to weeks, at least long enough to travel to a clear location): > Supernova SN 1054 was another widely observed event, with Arab, Chinese, and Japanese astronomers recording the star's appearance in 1054 AD. It may also have been recorded by the Anasazi as a petroglyph. This explosion appeared in the constellation of Taurus, where it produced the Crab Nebula remnant. At its peak, the luminosity of SN 1054 may have been four times as bright as Venus, and it remained visible in daylight for 23 days and was visible in the night sky for 653 days. https://en.wikipedia.org/wiki/History_of_supernova_observation https://en.wikipedia.org/wiki/History_of_supernova_observati...
- proactivesvcs 7y ago
  If you're anywhere near Pete from the UK's The Sky At Night programme, when a camera is on him, you can be guaranteed to be clouded out!
sktrdie 7y ago
I am surprised it didn't happen. I think it's 1 star that goes supernova per galaxy every 100 years. Why didn't we see any yet? Reference: https://www.space.com/6638-supernova.html https://www.space.com/6638-supernova.html "On average, a supernova will occur about once every 50 years in a galaxy the size of the Milky Way" Why don't we see them with the naked eye?
- ceejayoz 7y ago
  > Why don't we see them with the naked eye? Same reason you can't read a book by looking at the binding. Most are obscured by gas, the galactic core, etc. as we view the galaxy edge-on. They also have to be fairly close to be visible to the naked eye. For example, https://en.wikipedia.org/wiki/SN_1987A https://en.wikipedia.org/wiki/SN_1987A was only about as far away as the other side of the Milky Way, and was perhaps barely visible in a dark sky at its peak magnitude.
- cwbrandsma 7y ago
  We don't see all of the Milky way as is, like the other side of the milky way is out of our view. https://www.universetoday.com/23173/the-milky-way-from-earth/ https://www.universetoday.com/23173/the-milky-way-from-earth... So that metric could be correct, but the supernova is outside of what we see.
- Someone 7y ago
  Let’s do some back-of-the-envelope reasoning. https://en.wikipedia.org/wiki/Supernova https://en.wikipedia.org/wiki/Supernova: ”The peak optical luminosity of a supernova can be comparable to that of an entire galaxy” There are over 2 trillion galaxies (https://en.wikipedia.org/wiki/Galaxy https://en.wikipedia.org/wiki/Galaxy), of which less than 10 (https://en.wikipedia.org/wiki/Galaxy#Distinction_from_other_nebulae https://en.wikipedia.org/wiki/Galaxy#Distinction_from_other_...) are visible with the naked eye. ⇒ ballpark, it seems only about one in 200 billion supernovae will be visible to the naked eye. Taking 1/50th supernova per galaxy per year, we get 4 billion supernovae per year, so we would expect to see one every 50 years, on average. Also, that can be as comparable may be fairly exceptional, the Milky Way may be above average size for a galaxy, or we just didn’t notice them (unless it were very bright, few people would notice a new ‘star’ showing up for a few days/weeks, and they may have been ‘behind’ other stars. That can easily happen for stars in the galactic plane of the Milky Way) Certainly, historically, we simply didn’t really look. It was not as if we had a world-wide scan for supernovae even 50 years ago (do we even have one today, or are we mostly discovering them by going through decades-old photos?)
pwenzel 7y ago
Something not experienced since the Great Collapsing Hrung Disaster of Gal./Sid./Year 03758!

Imagine being alive when it goes supernova (relatively to us on earth). That would be a spectacular thing to witness.

mongol 7y ago

I am sure it will be cloudy where I am.

ceejayoz 7y ago
Betelgeuse would be visible for weeks, and be at its brightest point (as bright as the full moon) for several days.
sixstringtheory 7y ago
Even if you live in the tropics and it’s during the rainy season, you still have a good chance of seeing one. It’s not like a solar eclipse where you have very short time period to view it, it could last weeks to years (of course the peak would be shorter, but probably still on the order of days to weeks, at least long enough to travel to a clear location): > Supernova SN 1054 was another widely observed event, with Arab, Chinese, and Japanese astronomers recording the star's appearance in 1054 AD. It may also have been recorded by the Anasazi as a petroglyph. This explosion appeared in the constellation of Taurus, where it produced the Crab Nebula remnant. At its peak, the luminosity of SN 1054 may have been four times as bright as Venus, and it remained visible in daylight for 23 days and was visible in the night sky for 653 days. https://en.wikipedia.org/wiki/History_of_supernova_observation https://en.wikipedia.org/wiki/History_of_supernova_observati...
proactivesvcs 7y ago
If you're anywhere near Pete from the UK's The Sky At Night programme, when a camera is on him, you can be guaranteed to be clouded out!

sktrdie 7y ago

I am surprised it didn't happen. I think it's 1 star that goes supernova per galaxy every 100 years. Why didn't we see any yet? Reference: https://www.space.com/6638-supernova.html https://www.space.com/6638-supernova.html "On average, a supernova will occur about once every 50 years in a galaxy the size of the Milky Way" Why don't we see them with the naked eye?

ceejayoz 7y ago
> Why don't we see them with the naked eye? Same reason you can't read a book by looking at the binding. Most are obscured by gas, the galactic core, etc. as we view the galaxy edge-on. They also have to be fairly close to be visible to the naked eye. For example, https://en.wikipedia.org/wiki/SN_1987A https://en.wikipedia.org/wiki/SN_1987A was only about as far away as the other side of the Milky Way, and was perhaps barely visible in a dark sky at its peak magnitude.
cwbrandsma 7y ago
We don't see all of the Milky way as is, like the other side of the milky way is out of our view. https://www.universetoday.com/23173/the-milky-way-from-earth/ https://www.universetoday.com/23173/the-milky-way-from-earth... So that metric could be correct, but the supernova is outside of what we see.
Someone 7y ago
Let’s do some back-of-the-envelope reasoning. https://en.wikipedia.org/wiki/Supernova https://en.wikipedia.org/wiki/Supernova: ”The peak optical luminosity of a supernova can be comparable to that of an entire galaxy” There are over 2 trillion galaxies (https://en.wikipedia.org/wiki/Galaxy https://en.wikipedia.org/wiki/Galaxy), of which less than 10 (https://en.wikipedia.org/wiki/Galaxy#Distinction_from_other_nebulae https://en.wikipedia.org/wiki/Galaxy#Distinction_from_other_...) are visible with the naked eye. ⇒ ballpark, it seems only about one in 200 billion supernovae will be visible to the naked eye. Taking 1/50th supernova per galaxy per year, we get 4 billion supernovae per year, so we would expect to see one every 50 years, on average. Also, that can be as comparable may be fairly exceptional, the Milky Way may be above average size for a galaxy, or we just didn’t notice them (unless it were very bright, few people would notice a new ‘star’ showing up for a few days/weeks, and they may have been ‘behind’ other stars. That can easily happen for stars in the galactic plane of the Milky Way) Certainly, historically, we simply didn’t really look. It was not as if we had a world-wide scan for supernovae even 50 years ago (do we even have one today, or are we mostly discovering them by going through decades-old photos?)

pwenzel 7y ago

Something not experienced since the Great Collapsing Hrung Disaster of Gal./Sid./Year 03758!