[HN Gopher] How many supernova explode every year?
       ___________________________________________________________________
        
       How many supernova explode every year?
        
       Author : rbanffy
       Score  : 348 points
       Date   : 2025-04-12 06:48 UTC (3 days ago)
        
 (HTM) web link (badastronomy.beehiiv.com)
 (TXT) w3m dump (badastronomy.beehiiv.com)
        
       | darthrupert wrote:
       | The whole things seems like such a massive living system that I
       | cannot help guessing that what we think of as universe is just a
       | somewhat large single creature.
        
         | ndsipa_pomu wrote:
         | It's an appealing idea, but surely there'd be insurmountable
         | problems with the distance/time involved for any part to
         | communicate to another part? It'd be like trying to run a
         | computer with a clock that takes millions (billions?) of years
         | to make a single tick. I just don't see that it's at all
         | feasible and that's without even trying to guess as to how
         | different parts can change behaviour depending on its
         | environment (one commonly used requirement of "life").
        
           | tialaramex wrote:
           | > a clock that takes millions (billions?) of years to make a
           | single tick
           | 
           | Much worse than that, the universe is enormous and it is
           | expanding faster than the maximum possible velocity, as a
           | result such a clock could never complete a single tick.
        
           | dkersten wrote:
           | What's wrong with it taking a billion of our years to tick?
           | Just because we, smaller than microscopic beings compared to
           | the size of the larger structures we observe, find it to be a
           | vastly long time, doesn't mean that it's a long time for
           | something the size of the observable universe.
           | 
           | For a single bacteria cell, our timeframes must seem immense
           | too.
           | 
           | I'm not saying it's particularly likely, but it's a trap to
           | think that just because you can't fathom the scales that
           | makes it impossible. The universe is huge and very very old.
           | It can afford to wait what is a long time to us for something
           | to happen.
           | 
           | I do think you're likely right in practice though, and that
           | it _is_ too long for the universe to be an organism. But who
           | knows. We already know that mathematically speaking the heat
           | death of the universe looks identical to a very zoomed in big
           | bang, maybe we just need to zoom out a few billion orders of
           | magnitude to see the big picture, where the vast distances
           | and time scales we see appear as little more than micrometers
           | and microseconds apart...
        
             | ndsipa_pomu wrote:
             | The problem with zooming out is that the speed of light
             | sets a specific size/time scale so the more zoomed out you
             | get, the more disconnected the big picture is. The
             | observable universe is a mere 93 billion light-years
             | across, so there's a limit on how far it makes sense to
             | talk about zooming out. Also, with the universe expanding,
             | the observable size will reduce over a long time period.
             | 
             | The scales involved are vastly different than the minor
             | difference in scales between bacteria and us - we don't
             | have to worry about the speed of light for anything that we
             | currently consider alive.
        
               | mrep wrote:
               | > The observable universe is a mere 93 billion light-
               | years across
               | 
               | As a non-astronomer, that number still always boggles my
               | mind.
               | 
               | > Also, with the universe expanding, the observable size
               | will reduce over a long time period.
               | 
               | Also boggles my mind. Also makes me think of doctor who
               | when the stars start disappearing. I need to rewatch
               | that...
        
               | daxfohl wrote:
               | Not to mention, the signal strength seems too weak and
               | unstructured to be useful as a basis of any higher order
               | machination. A supernova is unlikely to cause much of
               | anything outside of its immediate vicinity. Unlike neural
               | pathways that are highly structured and mostly lossless,
               | radiation disperses out in all directions and weakens
               | with the square of the distance.
               | 
               | Unless there's something big we're missing. Maybe the
               | cores of stars contain the final ingredient required for
               | DNA formation or something.
        
         | Cyphase wrote:
         | This reminds me of this quote from Jill Tarter of SETI,
         | specifically the last sentence:
         | 
         | "Might it be the discovery of a distant civilization and our
         | common cosmic origins that finally drives home the message of
         | the bond among all humans? Whether we're born in San Francisco
         | or Sudan or close to the heart of the Milky Way Galaxy, we are
         | the products of a billion-year lineage of wandering stardust.
         | We, all of us, are what happens when a primordial mixture of
         | hydrogen and helium evolves for so long that it begins to ask
         | where it came from."
         | 
         | source:
         | https://www.ted.com/talks/jill_tarter_join_the_seti_search (@
         | 3:02)
        
           | yieldcrv wrote:
           | I think this is not too difficult for humans to comprehend,
           | it just doesn't address the resource appropriation and
           | geographic property claims on this planet. Aside from
           | generational interest, conflict areas tend to have something
           | obviously appealing about them, so there's nothing that a
           | bigger picture nihilism helps with.
        
           | jajko wrote:
           | Too idealistic view on human nature. We discovered vastly
           | different cultures in the past, no hint of humility (rather
           | exact opposite) or bonding, unless we find a common enemy.
        
             | Wobbles42 wrote:
             | Taken cynically though, is this quote not simply describing
             | the ultimate common enemy?
        
         | SwtCyber wrote:
         | There's something kinda poetic (and maybe even logical) about
         | the idea that what we perceive as scattered galaxies and
         | physics is actually just the internal processes of something
         | far bigger than we can comprehend.
        
           | jxf wrote:
           | Poetic, or maybe Lovecraftian. A lot of "cosmic horror" has
           | the trope of vastnesses too big to comprehend, where even
           | trying to think about it (or in some cases merely learning of
           | the possibility) causes you to go mad.
        
           | ravetcofx wrote:
           | Some might call that God. Or at least some form of Pantheism
        
         | aoeusnth1 wrote:
         | Well, if physicalism is true then consciousness is a phenomenon
         | of quantum fields, which span the universe. So yes, stretching
         | the definition of creature, this could be interpreted as
         | literally true.
        
       | drbig wrote:
       | The universe is vast and full of nothing...
       | 
       | Which in case of explodey stars is a very good thing indeed!
        
         | subscribed wrote:
         | It's fun to think that at some point it will be actually vast
         | and completely dark
        
           | jvm___ wrote:
           | https://youtu.be/uD4izuDMUQA?si=LcVxE3w-ohGqZAr7
           | 
           | If you need some existential dread. It's a hypothetical video
           | to portray the rest of the universe, the time speed moving
           | forward doubles every 5 seconds - and it's 29 minutes long...
        
             | Obscurity4340 wrote:
             | Really incredible video, thanks a quadrillion
        
           | rbanffy wrote:
           | We have a couple trillion years to figure out a way to fix
           | that.
        
             | frainfreeze wrote:
             | Does it need fixing?
        
               | rbanffy wrote:
               | Since I'd like to live forever, then yes.
        
               | db48x wrote:
               | What you really want to do is put out the stars sooner
               | then, and feed all the hydrogen into the supermassive
               | black hole at the center of the galaxy. Dump in all the
               | mass in the galaxy and all of its satellites and
               | everything from Andromeda and its satellites too and it
               | will grow. Nudge Andromeda's central black hole into
               | orbit around ours so that they merge, etc, etc. Grow it
               | big enough and and you can build a Birch World around it,
               | with a surface area larger than all the planets in those
               | galaxies put together. All of the exploration with none
               | of the boring travel in between interesting places! You
               | can seed it with life from every planet your civilization
               | ever encountered and watch all those ecosystems compete
               | and hybridize as you while away the years. How many years
               | would you have?
               | 
               | While dumping matter into a black hole destroys the
               | matter, it doesn't destroy the mass. It just confines all
               | of the mass in one place. Powering your Birch World is
               | just a matter of using the Penrose process to extract
               | energy from the black hole for the next few million
               | trillion trillion trillion trillion trillion trillion
               | trillion years (about 3x10104 years give or take a few).
               | The stars will only last for about a million trillion
               | years (1020 years plus or minus a bit), so this plan
               | extends your your lifetime by a factor of a trillion
               | trillion trillion trillion trillion trillion years.
               | 
               | Maximal extension perhaps, but not quite forever. Forever
               | takes a lot more work.
        
               | mietek wrote:
               | I would like to hear what you have to say about forever.
        
               | lazide wrote:
               | I imagine step 1 will be figuring out a way to reverse
               | entropy?
        
               | rbanffy wrote:
               | Something about there being light, IIRC.
        
               | db48x wrote:
               | That's actually [the _last_ question](https://users.ece.c
               | mu.edu/~gamvrosi/thelastq.html), not the first.
               | 
               | I liked the DS9 episode where the mutants realized that
               | the universe was collapsing into the Big Crunch, so they
               | demanded "antigravity generators, lots of them!" Their
               | cosmology was wrong, but only because the show had the
               | misfortune to be written in the past. Their enthusiasm
               | was great :)
        
               | 6LLvveMx2koXfwn wrote:
               | man, I couldn't think of anything worse - except maybe
               | dynamic types
        
               | 8fingerlouie wrote:
               | 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 10000000000000000
               | 000000000000000000000000000000000000000000000000000000000
               | 000000000000000000000000000000000 years
        
               | the_af wrote:
               | 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".
        
               | amelius wrote:
               | Are you sure? At some point you have heard every possible
               | joke that can be told in a timeframe of 10 minutes, 1000
               | times.
        
               | Wobbles42 wrote:
               | It's very unlikely that I am capable of remembering every
               | single joke that can be told in a timeframe of 10
               | minutes. If you were to take every such joke in a random
               | order and put that on a loop, the experience would likely
               | be one of perpetual novelty, even if you repeated it 1000
               | times.
        
               | amelius wrote:
               | How about: every day there is a small but finite
               | probability that you fall into a deep pit, and it may
               | take years before people find you.
        
               | pixl97 wrote:
               | >Since I'd like to live forever, then yes.
               | 
               | Please read this article first before damning yourself to
               | an unimaginable hell.
               | 
               | https://waitbutwhy.com/2014/11/1000000-grahams-
               | number.html
        
               | Wobbles42 wrote:
               | I have to imagine that very few people would make
               | statements like this if we lived in a universe where
               | there was any real danger of it happening. It would be
               | interesting to talk to humans that have lived even a few
               | hundred subjective years, if any existed. That seems to
               | be enough time to lead to very different perspectives on
               | something like immortality. Given the information storage
               | constraints of our minds, I wonder if there is even some
               | age that makes immortality subjectively different than
               | very long life. We don't seem to be capable of
               | remembering even a full decade of experience. By the time
               | you reach a few hundred years of age, would you have any
               | memories at all of your first century? You might not have
               | experienced a single "death" event, but the "you" that
               | was born may have long since died.
        
             | loloquwowndueo wrote:
             | We don't need to fix that, do we? Just let it be. You'll be
             | long dead anyway.
        
               | h4ck_th3_pl4n3t wrote:
               | > We don't need to fix that, do we? Just let it be.
               | You'll be long dead anyway.
               | 
               | Spotted the republican
        
               | selectnull wrote:
               | I guess even a republican can be right?
        
               | h4ck_th3_pl4n3t wrote:
               | /dev/random is right sometimes, too.
        
               | loloquwowndueo wrote:
               | Who, the guy I replied to who expects to be around in a
               | trillion years and wants to live forever? Yeah, peak
               | republican right there.
        
             | Wobbles42 wrote:
             | Or to acquire the wisdom to accept it. We certainly are far
             | too young to have a perspective to say which course of
             | action is better -- or indeed to define what "better"
             | means.
        
           | huxley wrote:
           | One of the best infinitive canvas webcomics ever was done on
           | that topic by Drew Weing:
           | https://www.drewweing.com/puppages/13pup.html
        
         | layer8 wrote:
         | It's full of radiation everywhere, regardless in which
         | direction we look and how highly we resolve it.
        
       | roenxi wrote:
       | We're dealing with the sum total of everything, if the true
       | nature of things is that there are a finite number of supernovas
       | I'd be surprised. The real shock is how small the number of
       | supernovas is and how young everything seems to be in the known
       | universe (the age of the observed universe is estimated at maybe
       | double digit billion years).
       | 
       | These are tiny numbers given that we're quite possibly dealing
       | with infinity in both time and space. I judge it one of the
       | stronger arguments in favour of the universe being constructed
       | (or, more likely, there is a lot out there we can't see). If god
       | built a universe numbers like 1 supernova a century make some
       | sense for artistic value.
        
         | eurekin wrote:
         | Isn't the observable universe finite? There can't be a infinite
         | number of anything in a space of radius R, even if R is very
         | big.
        
           | chasil wrote:
           | Anything moving beyond the Cosmological Horizon can no longer
           | be seen.
           | 
           | As I understand it, a frozen image will remain for a time and
           | fade, growing increasingly red shifted.
           | 
           | https://en.m.wikipedia.org/wiki/Cosmological_horizon
        
         | foxglacier wrote:
         | You can't compare a number of years or events with infinity.
         | Saying it's tiny or huge makes no sense whatsoever.
         | 
         | What amazes me is how young the universe is compared to life.
         | The universe is only about 4 times as old as life on Earth.
        
           | roenxi wrote:
           | The comparison can be made; almost all positive integers
           | can't practically be represented in hindu-arabic because they
           | are too large. If we're dealing with numbers that can be
           | scribed in a few seconds they are small in a meaningful way.
           | 
           | We'd expect that the mathematicians would need to come up
           | with a new notation to represent the age of the universe.
        
           | Wobbles42 wrote:
           | Or to flip that around, life has existed on Earth for about
           | 25% of the lifetime of the universe.
           | 
           | The fact that we are part of that life introduces some nasty
           | sampling biases, but if we find even one more planet that
           | shows a similar ratio, the implications will be that life is
           | ubiquitous.
        
         | mrep wrote:
         | > 1 supernova a century
         | 
         | A century being the amount of time it takes earth, one specific
         | planet to orbit its star 100 times? What about all the other
         | planets and stars?
        
           | Wobbles42 wrote:
           | A century is approximately three billion seconds, the second
           | being variously defined across history as a multiple we find
           | convenient of whatever universal natural constant we can most
           | precisely measure -- most recently 10 billion or so of a
           | specific type of vibration of cesium atoms.
           | 
           | All the other stars and planets would have the same
           | experience, though their local orbital periods might result
           | in different units of expression being more convenient.
           | 
           | Of course, as we leave our galaxy they would also be in
           | significantly different reference frames and perhaps
           | experience the rate differently as a result. We are assuming
           | that, statistically, our relative velocity is not special and
           | they see roughly the same relationship between red shift and
           | distance that we do.
        
         | yzydserd wrote:
         | its 1 supernova per century per galaxy. there are many
         | galaxies: more than 10 stars go supernova every second across
         | the universe. tens of thousands have gone supernova since the
         | article was posted to HN. tiny percentages in a large sample
         | are huge numbers, you might even say 'astronomical'.
        
           | Wobbles42 wrote:
           | There is a really good intuitive analogy hiding here for the
           | scale of the universe:
           | 
           | Our galaxy is to the observable universe as a tenth of a
           | second is to your entire lifetime.
        
       | jampekka wrote:
       | I couldn't spot the supernova and there's no answer to where it
       | is. :'(
        
         | ndsipa_pomu wrote:
         | It's in NGX 1566
        
         | pansa2 wrote:
         | Bottom-left corner
        
         | dwighttk wrote:
         | Cross your eyes and lay the two images over each other and it
         | pops out (bottom left of the ring)
        
       | tialaramex wrote:
       | That's one of my favourite hints in Outer Wilds. You will see a
       | Supernova. Not with a fancy telescope, it's visible to the naked
       | eye, and if you watch the sky you'll see another soon enough. You
       | can see this right at the start, and unlike the random direction
       | of the probe launch you don't need any game lore to, if you're
       | smart enough, put two and two together.
        
         | SwtCyber wrote:
         | Honestly one of those rare games that makes you feel like a
         | real explorer, not just someone following a path the devs laid
         | out.
        
           | danso wrote:
           | Truly one of the most purest of video games in terms of
           | player freedom, I'm still sad that I didn't think to record
           | my own playthrough as everyone's path of discovery is more or
           | less unique.
           | 
           | The freeform gameplay and incredible ending makes OW easily
           | my pick for best game of all time, even though it's also my
           | least replayed favorite game.
        
         | me_me_me wrote:
         | I hope that game will be treated like LothR or Shakespeare, it
         | is truly special experience.
        
         | marklar423 wrote:
         | It's funny, I noticed I happening and thought it was proof of
         | the opposite - that there had to be some artificial cause for
         | the supernovae (including the Sun), because a real supernova
         | takes many years to progress, not 20 minutes.
         | 
         | Even after visiting the Sun Station I didn't believe it and
         | thought it was a narrative red herring....so the ending was a
         | surprise to me. Somehow.
        
       | deadbabe wrote:
       | Can the thread title be rewritten to be less obnoxious? "How many
       | supernova explode every year?" is fine. This isn't Reddit. Thread
       | titles should not imply some kind of personality or use cliche
       | meme speak. The all caps is definitely an abomination.
        
         | fooker wrote:
         | Please read the article along with bikeshedding titles. It's a
         | good one.
        
           | bonoboTP wrote:
           | The article itself is also written in that kind of quirky
           | meme personality tone. I guess some find it relatable and
           | humorous. Others (like me) find it obnoxious. Matter of taste
           | or perhaps of age bracket. This is the text version of
           | "Youtube voice", which is also evidently successful but not
           | all like it.
        
           | deadbabe wrote:
           | No. The title sounds like low effort clickbait trash.
        
             | 9rx wrote:
             | Clickbait is appealing. This sounds like the opposite.
        
         | Timwi wrote:
         | Agree. For the record (in case it gets changed), the title at
         | time of writing is "Wait. HOW MANY supernova explode every
         | year?".
        
       | herendin2 wrote:
       | 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 supernovae). Thanks: yzydserd and zild3d
        
         | Someone wrote:
         | > If got the math right, then about 1 in every 32,000 stars in
         | the universe goes supernova each year
         | 
         | Can't be right, can it? It would make the Sun (over 4 billion
         | years old) an enormous outlier.
         | 
         | It also would mean stars, on average, do not get very old. Over
         | 10% of the stars that the ancient Greeks saw in the sky would
         | have to have gone supernova since then.
        
           | herendin2 wrote:
           | > Can't be right, can it? It would make the Sun (over 4
           | billion years old) an enormous outlier.
           | 
           | Yes. That fact that I'm thinking made me think I was
           | certainly wrong
        
           | crag-jene wrote:
           | Not all stars can go supernova. Sol will never go supernova.
           | Only very massive stars can--or stars that become very
           | massive by absorbing other stars.
        
             | btilly wrote:
             | Binary white dwarf systems can also go supernova, even if
             | the combined mass is not that large as far as stars go.
        
         | zild3d wrote:
         | He mentioned a rough estimate of one per century per galaxy.
         | Estimate for average stars per galaxy is 100 million, which
         | would be 1 in 10 billion stars every year
        
         | yzydserd wrote:
         | A star "lasts" about 10 billion years, so you'd expect about 1
         | in 10 billion stars to 'die' each year, but only a tiny
         | proportion (the very largest) go supernova.
         | 
         | Numbers are huge. Even tiny ratios mean something like 10-100
         | stars go supernova every single second somewhere in the
         | universe.
         | 
         | Sounds a lot? Only about 1 star per galaxy goes supernova per
         | century. A lot of galaxies.
         | 
         | Mindblowing.
        
           | arp242 wrote:
           | The lifespan of stars varies a lot by type and size, with
           | largest stars having a very short life-span of maybe a few
           | dozen million of years and small ones up to dozens of
           | billions of years. I'm not sure what the average is.
        
           | icehawk wrote:
           | So only 0.12% of all main sequence stars, have the mass that
           | can become the most common type of supernova, and they
           | apparently only last for about 100 million years.
        
           | throwawaymaths wrote:
           | what's the rate of Type Ia supernovas? Higher I would guess?
           | (n>=2-aries are common and medium mass main sequence stars
           | are common, though it takes them a while to get to white
           | dwarf)
        
             | icehawk wrote:
             | 1/2 as common. https://astrobites.org/2022/04/16/template-
             | post-9/#:~:text=T...
        
           | jibe wrote:
           | Wouldn't the creation dates of stars be clustered around
           | certain points in time. So the supernovas should also happen
           | in groups?
        
           | Tuna-Fish wrote:
           | > A star "lasts" about 10 billion years, so you'd expect
           | about 1 in 10 billion stars to 'die' each year, but only a
           | tiny proportion (the very largest) go supernova.
           | 
           | This analysis really doesn't work. Star lifespan is inversely
           | correlated to size. A star large enough to just barely go
           | supernova is only going to live for ~100M years, and as they
           | get bigger, the lifespans fall rapidly.
           | 
           | (Why? Because gravity is what provides the pressure for
           | fusion to happen, and so more gravity means fusion happens
           | faster. For large stars, the luminosity is something like the
           | mass to the 3.5th power. Also, convection works less well for
           | larger stars, so as stars grow bigger, ever smaller
           | proportion of the star takes any part in the fusion reactions
           | in the core.)
        
         | dostick wrote:
         | 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.
        
           | tialaramex wrote:
           | There is no reason to expect any particular number of
           | universes. We've observed exactly one, this one, which had to
           | exist or else we wouldn't be here to observe that it existed.
           | 
           | Our universe is finite, so although it is unbounded (lacks
           | edges) there aren't an infinite number of anything in it,
           | galaxies, stars, M&Ms, grains of sand, atoms of hydrogen all
           | finite.
        
             | atq2119 wrote:
             | Has that really been established? The observable universe
             | is finite, yes, but I wouldn't think that automatically
             | implied that the universe as a whole is.
        
               | pixl97 wrote:
               | Simply put we can't know and we can never know _if the
               | universe is flat_. Now, if the universe has a curvature
               | then we could use that as a baseline for the size of the
               | universe, but as of so far we 've not detected one.
        
           | andyjohnson0 wrote:
           | > 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.
        
             | dostick wrote:
             | Yes we don't know if other universes exist. So it's 50/50
             | infinity or one. Then if our universe came into existence,
             | then probability is not 50/50, because we know that
             | something exists, therefore something else is more likely
             | to exist, probability towards infinity.
             | 
             | If you were observer of emptiness and no universe or
             | anything existing then you would say it's more likely there
             | will be nothing, so probability towards zero.
             | 
             | Not to forget the recursion. There's likely universes
             | within our elementary particles or our universe is a
             | particle in parent one.
        
               | pfdietz wrote:
               | > There's likely universes within our elementary
               | particles or our universe is a particle in parent one.
               | 
               | This is a very nonstandard use of the word "likely".
        
               | 12_throw_away wrote:
               | probability does not work that way
        
       | dr_dshiv wrote:
       | The most stars a person can see with the naked eye? About 8000.
       | 
       | And, less than half that, actually -- since we can't see the
       | other side of the hemisphere
        
       | SwtCyber wrote:
       | Absolutely mind-blowing how much our ability to observe the
       | universe has exploded
        
         | a3w wrote:
         | exploded, he-he.
        
         | Wobbles42 wrote:
         | Arguably, our ability to observe in any meaningful sense is
         | still limited to light waves occuring inside a volume not much
         | larger than the earth itself. I mean this in more than just a
         | semantic sense surrounding the verb "observe" -- for all
         | practical purposes everything outside of our solar system is
         | indistinguishable from a preprogrammed light show being
         | projected on a sphere centered on our sun with a diameter of
         | less than a light year. There is a decent chance that will
         | never change. The sheer size of the universe traps us in the
         | ultimate version of Plato's cave.
        
         | layer8 wrote:
         | Now many minds per second does it blow?
        
       | thih9 wrote:
       | > [Supernova discovery statistics for 2021] says there were
       | 21,081 supernovae seen in 2021
       | 
       | > When the Vera Rubin survey telescope goes online, it's expected
       | to see hundreds of thousands of supernovae per year by itself.
        
         | whoisthemachine wrote:
         | Maybe they will have to transition from Base 26 counting to
         | Base 64!
        
           | IggleSniggle wrote:
           | It's in the article.
           | SN2067aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa vs
           | SN2067aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa. Apparently
           | astronomers find base26 very straightforward and reasonable!
        
             | IggleSniggle wrote:
             | 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
        
               | bee_rider wrote:
               | I guess we're already hitting four letter words, was
               | there a supernova "butt" last year?
        
               | moron4hire wrote:
               | No, but there was an "AHOY" https://www.wis-
               | tns.org/object/2024ahoy
        
               | bronson wrote:
               | No, but this is close: https://www.wis-
               | tns.org/object/2024ass
        
             | Voultapher wrote:
             | 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.
        
             | Wobbles42 wrote:
             | That is unfortunate. With only two prime factors, one of
             | which being 13, base 26 is even worse than base 10, and it
             | doesn't even have anatomical coincidence to recommend it.
             | Much better to use base 36 -- we have a ready made
             | character set for it by simply adding the digits to the 26
             | alphabetic characters. This gives us many more integer
             | prime factors. Not as good as base 60, but better than base
             | 26 and finger numbers.
        
               | dylan604 wrote:
               | Why the assumption that base36 would use the western
               | alphabet. If they use Cyrillic, they'd have 33 chars. If
               | they use Japanese, they'd have 46 chars. Using Hindi,
               | they'd have 50 chars.
               | 
               | https://wordfinderx.com/blog/languages-ranked-by-letters-
               | in-...
               | 
               | I have no clue as to the accuracy of this website, but
               | accuracy isn't something we strive for when making
               | ridiculous comments on the interwebs, is it?
        
               | Wobbles42 wrote:
               | Well, the assumption was based on the fact that they
               | chose base 26, and that the "26" came from the use of a
               | 26 character alphabet. The 10 Arabic numerals are then a
               | convenient character set to expand to 36, which is a much
               | nicer number base than 26.
               | 
               | Japanese could be combined with the Hindi character set
               | to yield base 96, which is fairly convenient. Cyrillic
               | would be harder -- perhaps the best options there would
               | be to drop a character to yield base 32, or perhaps 3
               | characters to yield base 30.
               | 
               | I'd argue that base 60 is probably the optimal number
               | base for nearly any use (with base 16 or 64 as close
               | second and third for working with binary data). Hindi's
               | 50 characters combined with our 10 Arabic numerals could
               | indeed be a great way to get there.
        
       | selectnull wrote:
       | Astronomers will find out that naming is hard once they need to
       | name 119741st supernova.
        
         | pelagicAustral wrote:
         | I think it will be far before that, once they start hitting
         | supernovae name jackpots like SN2026 cu*t et al.
        
           | selectnull wrote:
           | I know :) This one was just the first to came to mind.
        
       | lifeisstillgood wrote:
       | No wonder the Millennium Falcon takes so longer to calculate its
       | jump to hyperspace.
       | 
       | Tens of thousands a year is one an hour!
       | 
       | There are so many supernovae you really could bounce too close to
       | one and that _would_ end your trip real quick
        
         | ninkendo wrote:
         | Star Wars takes place entirely within one galaxy, and the
         | number of supernova per galaxy is something like 1 per century,
         | so, nah, Han was just bullshitting to stall for time while his
         | busted-ass computer cobbled together numbers.
        
           | IggleSniggle wrote:
           | Not only that, it happened a long long time ago. I'm no
           | astronomer; would that be more or less supernovae?
        
             | Wobbles42 wrote:
             | Indeed. They didn't say it happened an "int" time ago. They
             | didn't even say a "long" time ago. They said a "long long"
             | time. I'd have to pull up a copy of the C standard to be
             | sure, but even if the units of "time" are plank times, I
             | suspect the implications could easily be that the story
             | occurs before the big bang.
        
               | BenjiWiebe wrote:
               | I suspect you're thinking of a double (floating point). A
               | long long is only a 64 bit integer.
               | 
               | 2^64 planck times is 9.9e-25 seconds. Planck times are
               | really tiny.
               | 
               | 2^64 nanoseconds is 584 years.
        
           | wruza wrote:
           | Most movies don't even leave our stellar vicinity, because
           | they want to use hyped star/constellation names and these are
           | from the very local set of stars. Not only a naked eye sees
           | only around a few thousands stars, but most of them are
           | basically next door. The mean distance to the star that you
           | can see is <1% of galaxy size. Almost everything you see is
           | in a 10px circle on the 1080p fullscreen galaxy map.
        
       | henryway wrote:
       | Sounds like he was caught beneath landslide, in a champagne
       | supernova... a champagne supernova in the sky
        
       | croes wrote:
       | Was surprised by the ,,Und so weiter" in the text.
        
         | weard_beard wrote:
         | Das ist mir Wurst
        
       | nashashmi wrote:
       | And just when we add that variable to our formula we can finally
       | teleport ourselves on to hyperspace.
        
       | ben_w wrote:
       | 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...
        
         | wolfram74 wrote:
         | I would imagine the supernova rate to be higher in the early
         | universe, as we've already passed peak stellar formation rates
         | and the heavier (and shorter lived) stars were more likely to
         | be formed earlier when the average density of the universe was
         | higher.
        
         | ls612 wrote:
         | It probably isn't wildly lower today, we know of at least five
         | or six big supernovae in the Milky Way in the past millennium.
         | For 200B stars in our galaxy the size normalized rate implied
         | by that would be like one ever 300 years. So if you
         | extrapolated the Milky Way alone in (cosmological) modernity
         | you would get 10/sec not 30/sec.
        
           | btilly wrote:
           | There is dust between us and most stars in the Milky Way that
           | blocks them from view in visible light. Therefore we can only
           | see a fraction of the supernovae in the Milky Way.
           | 
           | It is substantially easier for us to see supernovae in other
           | galaxies that we're not facing edge-on. And we have a large
           | sample size of such galaxies. That's why our best estimates
           | of supernovae frequency are based on observations of such
           | galaxies, and not on our observations of the Milky Way.
        
       | rookderby wrote:
       | First off, dont look at the outer wilds discussion on here, just
       | play the game. Second - they didnt say how many letters we need
       | to encode all of the observable supernova in a given year! So 100
       | billion galaxies, 1 per year per galaxy, we have around 1 billion
       | to encode. Sorry two edits this moring, first one was right. due
       | to math without coffee. 1e9/26^6 is about 3, 1e9/26^7 is less
       | than one. So we might see 'SN2050aaaaaah'!
        
         | danso wrote:
         | LOL just started replaying OW for the first time in years, and
         | my immediate reaction to seeing this headline was to go to the
         | comments and make an OW reference
        
         | criddell wrote:
         | I bought Outer Wilds based on recommendations like yours and I
         | found it kind of boring. The world is mostly empty and the
         | repetitiveness wore me down. I didn't finish it.
         | 
         | It's a great looking game though and the first hour or two I
         | had a blast.
        
           | packetlost wrote:
           | Same here. I found the controls to be frustrating and the
           | game-play loop to be kinda dull. The _story_ on the other
           | hand, is very good. I get that the game-play is meant to
           | illicit _certain_ feelings, but it just didn 't do it for me.
           | I did enjoy reading a synopsis of the story on the wiki
           | though.
        
             | shhsshs wrote:
             | Question for you and commenter above, do you play games
             | with controls similar to Outer Wilds often? Do you play
             | many games in general? I've seen this comment a few times
             | and I'm curious why this is such a common talking point. I
             | thought the controls were very intuitive, so I'm curious if
             | it's a familiarity issue or something else.
        
               | criddell wrote:
               | I don't recall having any problems with the controls. As
               | long as I can invert the y axis, I'm a happy camper.
        
               | ykonstant wrote:
               | I don't play 3D games; I bought Outer Wilds for the
               | experience, was unable to understand the controls. I
               | tried really hard, but had to quit.
        
               | frabert wrote:
               | The thing about Outer Wilds for me is that it's a game
               | about exploration, but most attempts at exploration are
               | punished (limited time frame, sands suffocating you,
               | "ghost matter" kills...). They stuck with a "hard scifi"
               | control scheme where you control your character in 6dof
               | with inertia, which makes some things unnecessarily hard
               | and did not (IMO) add anything to the game itself. The
               | things you interact with in the world are also annoying
               | to use, like the machines where you need to slide a ball
               | around by locking it with your sight... Just let me press
               | a button already!
        
               | spookie wrote:
               | Did you play with a controller by chance? Asking because
               | I prefer first person view games on PC
        
               | frabert wrote:
               | Yes, the game told me it was the preferred way and I
               | followed the advice
        
               | spookie wrote:
               | fair enough!
        
               | Trixter wrote:
               | I did not play with a controller, which made Dark Bramble
               | effectively impossible to finish because the keyboard is
               | all-or-nothing thrust. Had to cheat to get past it. They
               | should have said that using a controller was mandatory,
               | not recommended.
        
               | 0cf8612b2e1e wrote:
               | I think there were two separate puzzles where I had
               | identified the correct solution, but the mechanics were
               | so clunky that my attempt failed. Making me waste time
               | exploring elsewhere. Had to consult a guide just to see
               | that I had unknowingly botched the physics. Which is an
               | awful experience for a puzzle game. Especially when the
               | clock is working against you and some of the set pieces
               | require very specific timing to interact with them (where
               | doors are only open for a certain few minutes in a run).
               | 
               | The game is definitely a unique experience, but some of
               | the design elements hamper the experience.
        
               | packetlost wrote:
               | First person games: yes, quite a lot. Flight sims with
               | wonky physics? No, not really at all.
               | 
               | Some of the controls were fine, but I found the ship
               | piloting experience to be barely usable and definitely
               | not enjoyable.
        
             | rbanffy wrote:
             | > The story on the other hand, is very good.
             | 
             | There seems to be lots of games that should have been
             | movies or series instead.
        
           | astroalex wrote:
           | This is tragic. It's one of favorite games of all time--heck,
           | one of my favorite media experiences, period. It's worth
           | pushing through until you get hooked.
        
           | glimshe wrote:
           | I rage quit Outer Wilds. So repetitive, I couldn't take it
           | despite the novel premise. The controls suck and I'm an
           | experienced player.
        
       | ur-whale wrote:
       | Spoiler alert:
       | 
       | > THIRTY SUPERNOVAE PER SECOND, over the entire observable
       | Universe.
        
         | Wobbles42 wrote:
         | If we have events occuring at some rate in the entire
         | observable universe, and that rate is one a human can easily
         | visualize (e.g. "30"), then the answer to the question "how
         | often do supernovas occur" is probably best summarized as
         | "almost never".
        
       | belter wrote:
       | The SuperNova Early Warning System (SNEWS): https://snews2.org/
       | 
       | brings together the fantastic [1] Super-Kamiokande, the [2]
       | IceCube, and other global detectors, to provide early warning of
       | Supernovas.
       | 
       | You can subscribe... https://snews2.org//alert-signup/
       | 
       | [1] https://en.wikipedia.org/wiki/Super-Kamiokande
       | 
       | [2] https://en.wikipedia.org/wiki/IceCube_Neutrino_Observatory
        
       | croisillon wrote:
       | maybe some Supernova-Names get deleted, like SN2021acab?
        
       | didgetmaster wrote:
       | Two questions come to mind.
       | 
       | 1) When was the last supernova observed in our own galaxy?
       | 
       | 2) How close would one have to be to be observed with the naked
       | eye?
        
         | ardel95 wrote:
         | 1604. One could say we are overdue. I'm not sure about dust or
         | other obstacles blocking it, but based on brightness alone a
         | supernova in our galaxy should be visible with naked eye.
        
           | ahazred8ta wrote:
           | 1604? Sort of; SN 1987A was visible to the naked eye at 3rd
           | magnitude. It was in the Large Magellanic Cloud, which is
           | _almost_ in our galaxy but not quite. 170k light years.
           | https://en.wikipedia.org/wiki/SN_1987A
        
       | jxf wrote:
       | I think this says less about supernovas and a lot more about how
       | staggeringly, incomprehensibly vast the observable universe it.
        
         | daxfohl wrote:
         | Or how small we are
        
         | BitwiseFool wrote:
         | It would be a tragic shame for life to inhabit such a vast
         | universe only for faster than light travel to be impossible.
        
       | coryfklein wrote:
       | Near the top he shows two photos of the Cartwheel galaxy, one
       | from 2014 and one from 2021 with the caption:
       | 
       | > Can you spot Supernova 2021 axdf?
       | 
       | Are you supposed to be able to spot the supernova?
       | 
       | All I've noticed is a couple of small stars that _disappear_ in
       | the latter photo, but this mostly seems to be because it 's more
       | blurry.
        
         | piaste wrote:
         | Use the cross-eye trick to superimpose the two pictures, then
         | it becomes quickly noticeable as it will appear to blink.
        
         | pansa2 wrote:
         | Bottom-left corner
        
       | kakuri wrote:
       | I really feel like this article should also mention the rate of
       | formation of new stars. According to [1] Universe Magazine the
       | James Webb telescope has revealed that more than 3,000 stars are
       | formed every second.
       | 
       | [1] https://universemagazine.com/en/james-webb-comes-closer-
       | to-r...
        
         | Taek wrote:
         | I don't understand this comment. Like yes, 3000 stars per
         | second, cool fact. But why would that fact make sense in the
         | article? The article was about being surprised by the name "SN
         | 2021 afdx", which has nothing to do with star formation.
         | 
         | In my opinion the article was great and is also complete. More
         | cool astronomy facts belong in some other article or format.
        
           | dgs_sgd wrote:
           | Because the amount of stars that can go supernova is limited
           | by how many stars there are in the first place? A comment
           | about the staggering rate of star formation makes sense to me
           | in relation to an article about the staggering rate of star
           | supernovas..
        
         | citizenpaul wrote:
         | Based on this about 5.5 million stars are created every 30
         | minutes and only about 1 start goes supernova in the same
         | period? This seems like it really reinforces the we are still
         | in the early stages of the universe theory if the ratios are
         | that imbalanced.
         | 
         | Still though the imbalance in those events makes me suspicious
         | that we are missing something.
        
           | BobAliceInATree wrote:
           | The vast majority of stars don't supernova.
           | 
           | Also, we're at the tail end of star-forming era. about 95% of
           | all the stars that will be formed, have already been formed.
           | 
           | https://www.scientificamerican.com/blog/life-
           | unbounded/the-s...
        
       | jl6 wrote:
       | Ah, the good old column naming convention from MS Excel. Now
       | _there's_ an amazing creation that occasionally explodes
       | catastrophically.
        
       | state_less wrote:
       | Reminds me of the last lines of the diamond sutra.
       | 
       | > So you should view this fleeting world--
       | 
       | A star at dawn, a bubble in a stream,
       | 
       | A flash of lightning in a summer cloud,
       | 
       | A flickering lamp, a phantom, and a dream.
        
       | rwky wrote:
       | This reminds me of a few years ago when I was doing my MSc our
       | group was learning how to work one of the remote telescopes and
       | we were asked to point it at the brightest object found by Gaia
       | that week and it turned out to be a supernova. Very cool for your
       | first observation using a remote telescope! If anyone wants to
       | see it here it is https://ibb.co/Kzqbfq30
       | 
       | And here is the Gaia data
       | http://gsaweb.ast.cam.ac.uk/alerts/alert/Gaia23bqb/
        
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