[HN Gopher] Constellations are younger than continents
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Constellations are younger than continents
Author : dash2
Score : 262 points
Date : 2023-12-25 05:39 UTC (17 hours ago)
(HTM) web link (www.lesswrong.com)
(TXT) w3m dump (www.lesswrong.com)
| runsWphotons wrote:
| How accurately could we predict when betelgeuse will go? What are
| the CIs?
| geuis wrote:
| Part of the problem is that direct observations of supernovas
| is small and indirect. We have small numbers of recorded
| occurrences to judge from.
| ianburrell wrote:
| Also, we don't have observations of the stars before
| supernova. Most are in other galaxies so don't even see the
| star. Betelgeuse is first case where we can observe late
| stage star closely.
| MengerSponge wrote:
| Literally any moment in the next 10000 years. The probability
| distribution (afaict) is pretty flat, and either 1000, 10000,
| or 1000000 years long.
| rini17 wrote:
| Animation from GAIA data:
| https://www.esa.int/ESA_Multimedia/Videos/2020/12/Gaia_s_ste...
| Rhaomi wrote:
| https://www.theonion.com/darling-i-will-give-you-the-moon-an...
| kybernetikos wrote:
| I think the constellations through the ages chart make it clear
| that orion has been recognisable long enough to see continents
| change and will be recognisable for a long time to come.
| bleuarff wrote:
| The article goes on to say these stars are very young at ~10My,
| which is about the smallest time scale at which you might
| notice some change on continents'aspect. So you're probably
| technically right, but by a very thin margin.
| layer8 wrote:
| Did you read the article? The stars in Orion are only between 6
| and 12 million years old, and the continents already looked
| almost the same as today in that time frame. Furthermore, they
| are types of stars that won't live very long, at most 20
| million more years. Betelgeuse will go supernova within just
| the next 100,000 years. The Orion stars will see a little bit
| of continental movement over their lifetime, but not "rise and
| fall".
| nickdothutton wrote:
| There is a nice simulation of constellations changing over time
| in one of the episodes of Sagan's Cosmos, where he explains
| parallax and some of the other important phenomena.
| 082349872349872 wrote:
| H A Rey _The Stars_ (1952) had a nice series of cartoons
| depicting a caveman, a grey-flannel-suit man, and a futuristic
| man all looking at their respective versions of the big dipper.
|
| The Barbers' _When They Severed Earth From Sky_ (2004)
| hypothesises that the various kingship changes in heaven of
| several ancient mythologies correspond to the precession of the
| solstices and equinoxes through the zodiac. Eg, for Greek
| mythology, they give: Head God Summer
| Spring CHAOS Libra Cancer
| ~6480 BC OURANOS Virgo Gemini
| ~4320 BC KRONOS Leo Taurus
| ~2160 BC ZEUS Cancer Aries
|
| along with parallel tables for Babylonian, Hittite, Phoenician,
| and Norse mythologies, and reference a different work which
| should give Germanic, Finnic, Iranian, Indian, and Chinese
| mythological shifts.
|
| According to this hypothesis, when the fall equinox moved into
| Virgo and Saturn and Jupiter came into conjunction with Pisces
| in 6 BC, many ancients took it as marking the advent of a new
| Kingdom of Heaven ruling a New Age, making them more
| susceptible to picking up new religions emanating from the
| middle east around that time, eg Mithraism.
|
| Does Virgil, writing ca 40 BC, predict the New Age? [Fourth
| Eclogue 4-10]
|
| > _Now is come the last age of Cumaean song; the great line of
| the centuries begins anew. Now the Virgin returns, the reign of
| Saturn returns; now a new generation descends from heaven on
| high. Only do you, pure Lucina, smile on the birth of the
| child, under whom the iron brood shall at last cease and a
| golden race spring up throughout the world!_
|
| (but note that by this counting the "Age of Aquarius" wouldn't
| be due to start until ca 2160; rather far off in human
| lifetimes from the 1960s)
| nickdothutton wrote:
| This is tremendous. One could write a book relating well
| documented history and mythology with the changing
| constellations.
| whartung wrote:
| I actually remember a couple of diagrams in a science book way
| back in elementary school, so we're talking 70s here, showing
| the Big Dipper today and what it would look like in 50,000
| years.
|
| It was a kind of weird feeling as a young boy "seeing" change
| to something considered so static, and all the deeper
| considerations from that.
| Tommstein wrote:
| I've played with Celestia and had it draw the constellations,
| then zoomed around the galaxy and seen how they got distorted
| as I moved away from Earth and saw them from different
| angles. Really drove home that the constellations are three-
| dimensional arrangements, not flat.
| NKosmatos wrote:
| This article brought back memories of when I was playing around
| with astronomy simulation software like Redshift by Maris
| Multimedia.
|
| I started searching for it, and as it usually goes with HN
| stories, I ended up on their new/modern version of it over at:
| https://redshiftsky.com
|
| A brief history of their famous titles (check also aviation) is
| over at: http://archaic.maris.com/content/indexe5cc.html
|
| Older versions of Redshift can be downloaded/found over at the
| Internet Archive:
|
| https://archive.org/details/redshift_202204
|
| https://archive.org/details/redshift2
|
| https://archive.org/details/Redshift_3_Maris_Multimedia_1998
| asystole wrote:
| There's also the FLOSS Stellarium: http://stellarium.org/
| bjackman wrote:
| Also: Polaris (the north star) is younger than sharks.
|
| (This one is less interesting as an overall observation about
| timescales though. Polaris is just quite a young star and sharks
| are quite and old life form).
| vasco wrote:
| Trees are also younger than sharks.
| froggit wrote:
| Sharks were ahead of their time.
| Sharlin wrote:
| As the article implies, all the brightest stars in Orion are
| younger than _hominids._ Indeed they formed around the time
| when the last common ancestor of humans and chimpanzees lived.
| kibwen wrote:
| Polaris as the north star is younger than the Roman Empire!
|
| Because of the precession of the Earth's axis, Polaris didn't
| become the north star until about 500 AD. To the ancient
| Egyptians, Thuban was the north star. When humans were first
| discovering agriculture 12,000 years ago, Vega was the north
| star.
|
| Wikipedia has a great table showing the cycle of north stars:
| https://en.m.wikipedia.org/wiki/Pole_star#Precession_of_the_...
| xapata wrote:
| So, that "I am as constant as the northern star" simile is a
| little mixed?
| MichaelZuo wrote:
| Constant for a few hundred years until they inevitably get
| knocked off track.
| throwup238 wrote:
| Another fun fact: very early humans ( _Australopithecus_ )
| coexisted with megalodons, giant dinosaur sharks that could
| swallow a hairless ape whole.
| Nition wrote:
| Sharks go back more than 3% of the way to the beginning of the
| universe.
| p-o wrote:
| These kind of facts always blow my mind. For instance, the Sun
| orbits the milky way once every 212m years.
|
| That means that if the sun existed from the big bang to now, it
| would have only done ~63 complete revolutions around Sagittarius
| A*. If you account for the Milky Way's creation, that number gets
| even lower. I'm no expert, so maybe this makes sense to someone
| who knows more about this, but it definitively feel weird to me.
| mihaitodor wrote:
| I wondered the same thing and I asked Sean Carroll about it
| [1]. He didn't go into much detail, but here is his answer:
|
| > I guess my only insight is, I'm not sure why you relate the
| number of revolutions that the Milky Way has made to its
| complex and symmetric structure. The spiral arms that you see
| in a galaxy like the Milky Way do not rigidly rotate with it,
| they are more like... This is complicated, but they are more
| like regions where star formation is going on, and therefore
| the galaxy is brighter rather than regions where there's more
| density or anything like that. So if you're worrying how the
| spiral structure forms. It can form pretty easily in one or two
| revolutions, I don't see why it would take even 68, much less,
| but need more than that.
|
| [1]
| https://www.preposterousuniverse.com/podcast/2023/10/09/ama-...
| firebot wrote:
| Problem with Sean and most cosmologists is they are
| proliferate regurgitates with little independent thought.
| ben_w wrote:
| Even before LLMs were dismissed as "stochastic parrots"
| (and even more so since then), I find myself noticing when
| people dismiss the intellectual capacity of entire groups.
|
| "Mickey Mouse degrees", https://xkcd.com/793/, the attitude
| displayed by the bully in "Zero for Conduct" and similar
| IRL dismissals of the entire ME area in the post 9/11
| discourse, mid-Brexit politicians saying the country had
| had enough of experts, some of my fist girlfriends'
| anecdotes from her childhood, town v gown, ...
| firebot wrote:
| I don't follow.
| ben_w wrote:
| You, like all my examples, are blithely dismissing
| everyone who does understand a subject that you don't
| understand.
| ryanklee wrote:
| I really don't understand how you can put forth a criticism
| like this and be so vague at the same time. It really
| undermines your credibility. Be specific or why bother.
| firebot wrote:
| I have no credibility.
|
| Sean jumps on the hype train all day long. I'm skeptical.
| I don't think this illustrious dark matter or big bang
| mean anything. So it's like that telephone game where
| Sean is the last person and gets to tell you what the
| first person said and he's always very excited but
| baseless. Really do like his energy. I just don't think
| he's much of an independent thinker.
| gattr wrote:
| Another fun fact: there are more trees on Earth (3x1012) [1]
| than stars in the Milky Way (1-4x1011).
|
| [1] "Mapping tree density at a global scale"
| https://www.nature.com/articles/nature14967
| dataflow wrote:
| That fact sounds like it will become fiction very very soon.
| :\
| fukpaywalls2 wrote:
| On the postive side, there's probably more microplastics in
| our oceans than there are stars in all of the galaxies
| summed together.
| tamimio wrote:
| Have another fact since we are talking about trees, wood is
| the rarest element in the universe, even more rare than
| diamonds, in fact, wood can only be found on earth! A piece
| of me dies every time I see someone cutting a tree for
| useless reasons.
| Solvency wrote:
| Wood isn't an element?
| explaininjs wrote:
| Do you think cutting a tree annihilates the wood?
| ben_w wrote:
| Depends on your definition of "tree".
|
| My follow-up fun fact is that even though "tree", like
| "fish", is a term of common parlance, there is _no_
| universally recognised and precise definition of the
| category, either botanically or in common language.
| defaultcompany wrote:
| Agreed. Another surprising one to me is that the earth itself
| has been around for about 1/3 the age of the universe. I always
| assumed that the timescale of the universe was vastly longer
| than the life of the earth.
| k7sune wrote:
| Wow it's amazing that we could somehow time the orbit period.
| FergusArgyll wrote:
| Life in West Virginia is younger than the mountains but older
| than the trees
| ggsp wrote:
| Isn't life everywhere older than the trees?
| hfgjbcgjbvg wrote:
| I believe it's a reference to a John Denver song.
| ggsp wrote:
| Oh, ha, thanks for pointing that out :)
| Semiapies wrote:
| If you take it as "life on land", it's accurate on both
| counts. Those are some old mountains.
| jameshart wrote:
| https://twitter.com/bookishseawitch/status/1572751278366949
| 3...
|
| "the appalachian mountains are older than saturn's rings.
| the appalachian mountains are older than dinosaurs. the
| appalachian mountains are older than trees. the appalachian
| mountains are literally older than BONES. the appalachian
| mountains should be regarded with pure terror."
| rpmisms wrote:
| Here's a yule-flavored reminder that Denver's talking about
| Western Virginia, since that's where the Blue Ridge mountains
| are.
|
| He'd also never been here, so he might have just been wrong.
| selimthegrim wrote:
| This is probably why West Virginia is never going to let go
| of Harper's Ferry now
| Geisterde wrote:
| Oh I dont know the history, but I think I could throw a
| baseball from the 7 and hit west virginia, and if you are on
| the country roads trying to get around the traffic headed up
| bluemount you could probably find yourself in west virginia
| pretty easy.
| 082349872349872 wrote:
| Speaking of never been there, I'm always amused by what you
| get when Dutch attempt to interpret the Denver lyrics:
| https://www.youtube.com/watch?v=ZVz_IJoyO6Y
|
| (or for that matter the German notion of western:
| https://www.youtube.com/watch?v=DZrXWdLxtfM )
| rpmisms wrote:
| The first one sent me into fits. The point is that we're
| old here, not the wild West. Hilariously, I live in one of
| the most German areas of Appalachia, so the people look
| more or less like my neighbors.
|
| The second one would fit in at the CMAs.
| krisoft wrote:
| Also, not to mention that constellations are a human made
| construct. It is like how day night cycles are natural, and have
| existed before us, but calling every seventh cycle "monday" is
| not.
|
| The stars and their appearance on the sky is natural like the
| day-night cycles, while how they are grouped together and what
| they are called is human made. (And different civilisations had
| wildly differing opinions on how this should be done.)
| nullindividual wrote:
| Wouldn't Saturday be the seventh cycle, given it is the end of
| the week?
| JadeNB wrote:
| > Wouldn't Saturday be the seventh cycle, given it is the end
| of the week?
|
| Every 7th cycle would be the _start_ of the week; the 6th
| cycle would be the end. (Think, for example, if you had a
| 2-day week; the 1st cycle would take you to the 2nd day.) But
| when the week starts is not universally agreed--I believe
| USians usually start it on Sunday, and Europeans usually
| start it on Monday.
| ianburrell wrote:
| There are seven day weeks, the 1st to 7th. The 8th day is
| the start of the next week. The 1st cycle is the 1st day.
| evanb wrote:
| 'Every' modifies the meaning. It's just as sensible and
| correct to say 'every second number is even' and 'every
| second number is odd'.
| nine_k wrote:
| No matter how one would choose to group stars in the sky, the
| point is that their relative angular closeness varies faster
| than that of continents on our planet.
| hinkley wrote:
| I wonder when we started telling stories about them though.
| There's not much to do once the sun sets, prior to the
| invention of the oil lamp.
|
| Unfortunately Orion is still older than most hominids. I can
| imagine a new constellation triggering the "need" for new
| stories, but only after language developed.
|
| And while I strongly believe we will continue to push back the
| beginnings of Man, and of civilization, we are probably past
| the inflection point. I suspect we aren't likely to quadruple
| the origin dates for our species. Which is what you'd need to
| have a plausible story about oral traditions affected by Orion
| sprouting a new star.
| __MatrixMan__ wrote:
| I was surprised to learn that Pangaea is believed to have formed
| and broke up at least five times so far.
| p3rls wrote:
| Tolkien himself was unsure if we were in the 6th or 7th age
|
| ---
|
| I doubt if there would have been much gain; and I hope the,
| evidently long but undefined, gap* in time between the Fall of
| Barad-dur and our Days is sufficient for 'literary
| credibility', even for readers acquainted with what is known or
| surmised of 'pre-history'
|
| I imagine the gap to be about 6000 years : that is we are now
| at the end of the Fifth Age, if the Ages were of about the same
| length as S.A. and T.A. But they have, I think, quickened; and
| I imagine we are actually at the end of the Sixth Age, or in
| the Seventh.
|
| Source - The Letters of J.R.R. Tolkien, Letter 211
| labster wrote:
| We have basically had to conclude that Tolkien's star
| Borgil[0] is Aldebaran, because Betelgeuse wasn't a red star
| in the classical era[1], or before.
|
| [0]: https://tolkiengateway.net/wiki/Borgil [1]:
| https://news.ycombinator.com/item?id=32478492
| andrewflnr wrote:
| Pangaea is only the name of the most recent supercontinent. The
| past ones all have their own names.
| https://en.wikipedia.org/wiki/Supercontinent
| 082349872349872 wrote:
| Of the 10 on that list, multicellular life appears around #8
| (Pannotia).
| knorker wrote:
| Another one: dinosaurs existed on the other side of the galaxy.
|
| The galaxy has revolved about half a revolution since then.
| Tommstein wrote:
| The Milky Way is also moving through space. So they actually
| existed way out in intergalactic space (probably).
| mncharity wrote:
| A UI can combine those two: Sun's galactic orbit as analog-
| clock selector, and MW motion (wrt CBR, towards Great
| Attractor) as a slider. Though IIRC, the range of a slider
| with a finger-tip sized MW is relatively limited. Yay
| implicit curriculum.
| antognini wrote:
| There is an interesting theory about the Pleiades star cluster
| [1]. The Pleiades are somewhat unique in that they are a
| prominent feature of the sky and close to the celestial equator.
| Because of that, they are visible to every population on Earth,
| and every culture has developed a story around them.
|
| Around 2/3 of cultures have a story in which there are seven
| things (seven sisters, seven boys, seven chickens, and so
| forth.). The other 1/3 of cultures have a story in which there
| are six things. And a surprising number of them have a story in
| which there were originally seven, but one got lost (like in the
| Greek myth of Electra).
|
| The interesting thing is that two of the stars in the cluster are
| quite close together and can't be distinguished by eye. A pair of
| astronomers looked at the proper motions of the stars in the
| cluster and figured out that tens of thousands of years ago these
| two stars were far enough apart that they could have been
| distinguished by eye. So it seems that early humans recognized
| the Pleiades as having seven stars and this persisted in the
| myths of most cultures for tens of thousands of years, even when
| the seventh star was no longer visible.
|
| [1]: https://arxiv.org/abs/2101.09170
| Amezarak wrote:
| Although I like the idea, there's no reason to posit the
| preservation of the myth of a lost star for tens of thousands
| of years. People can still see all Seven Sisters under the
| right conditions, and the right conditions were probably much
| more prevalent back before the insane degree of light and air
| pollution that exists today.
|
| https://skyandtelescope.org/astronomy-news/many-pleiades-can...
| dharmab wrote:
| Would this have been true in a society without optics and
| therefore corrective lenses?
| calamari4065 wrote:
| When I was young, I was told a story about how native
| tribes used the star as a vision test for warriors. Only
| people with excellent vision could discern the second star.
|
| No idea if there's any truth in the story, but I wouldn't
| be surprised
| antognini wrote:
| You're probably thinking of Mizar and Alcor, which are at
| the middle of the handle of the Big Dipper. This was used
| as a vision test in ancient times and in the middle ages.
|
| A fun fact is that it is actually six stars. Alcor is a
| binary star system and Mizar is a quadruple star system.
| calamari4065 wrote:
| That might be it. I was probably 10 at the time so I
| don't remember the details
| Amezarak wrote:
| Yes, nearsightedness is much worse in modern times. Many
| less people needed corrective lenses, even as they got
| older.
| calamari4065 wrote:
| This is one of my favorite stories.
|
| One of the best parts is the legend of the seven sisters in
| Australian aboriginal tradition.
|
| Theory goes that the legend far, far predates first contact
| with Europeans, so it must have come with the first aboriginal
| settlers when they sailed from Africa. Which would make it one
| of (if not the) oldest stories in history.
| tmnvix wrote:
| Sailed from Africa? I always thought they crossed the Torres
| Strait.
|
| On a related note, something that has always intrigued me is
| why there is no historical record of Polynesian arrival on
| the east coast of Australia.
| calamari4065 wrote:
| I admit I don't really know. The story I read suggested
| that settlers sailed from Africa directly. But I don't know
| what the actual scientific consensus is on this. Really I
| don't find it particularly interesting as it's mostly
| guesswork about something 65000 years ago
| Amezarak wrote:
| Considering all Seven Sisters are visible to people with good
| vision in sufficiently remote areas of Australia today, I
| don't know how one can draw any conclusions about how old the
| story is.
|
| Indeed, with sufficiently good conditions and good vision,
| you can see _more_ than seven. The Seven Sisters are just the
| brightest of the Pleiades.
| calamari4065 wrote:
| Because it's the same seven sisters legend as found in many
| other places around the world.
|
| Seven sisters chased into the sky by a hunter, and the
| seventh sister left the sky to marry the hunter.
|
| The aboriginals were isolated from the rest of the world
| for _tens of thousands_ of years. That their legend is
| nearly exactly the same as European legends is incredibly
| unlikely to be coincidence. More likely the legend of the
| seven sisters is a story that was first told before humans
| left Africa. All of the Pleiades legends must stem from
| that original story.
|
| The interesting part isn't that they have _a_ story about
| the Pleiades, but that it 's the _exact same_ story as
| everyone else. And they 've been telling it for tens of
| thousands of years before ever encountering the Europeans.
| Amezarak wrote:
| I am the last person to promote historical criticism over
| oral and written traditions, but the case is much weaker
| than what people who repeat this suggest.
|
| 1. There's a lot of stars, and they were very important
| to most every ancient culture on Earth.
|
| 2. Our pattern-matching brains are inclined to see
| vaguely similar things, even across different times and
| cultures.
|
| 3. Even so, there is very little overlap between
| Aboriginal constellations and other cultures'
| constellations.
|
| 4. The aboriginal Australians do not in fact all
| recognize the Pleiades. Some don't see it as a group at
| all. Other aboriginal groups actually note differing
| numbers of sisters (5-7) and have different stories about
| them, although the motif of fleeing from different men
| represented by different astronomical objects is a more
| common one than not.
|
| The case for this is nice to imagine but very weak. It is
| not the case that "they" have the "exact same story" at
| all.
| tsimionescu wrote:
| That's a cute idea, but it's extremely unlikely to be true. If
| nothing else, the human fascination with 7 is a much more
| likely explanation, especially since 6 is nowhere near as
| important a number in this way (1,2,3 and 7 are much more
| common in myths and fairytales).
| throwaway8877 wrote:
| Australian natives have stories than originate over 10000
| years ago that have been proven to be factual.
| explaininjs wrote:
| Humans have made stories about the stars for as long as there
| have been humans. Why do you think this is unreasonable?
| xigency wrote:
| It's not unreasonable per se but seems a weak hypothesis
| without more supporting evidence.
| vardump wrote:
| Humanity might one day spread to all over the galaxy by
| hitchhiking passing stars.
|
| Well, assuming we don't self-annihilate ourselves at some point.
| Or be destroyed by some cataclysm.
|
| I guess we'd better spread to as many locations in the solar
| system as, err, humanly possible.
| perlgeek wrote:
| Communication across interstellar space would be super slow,
| because the speed of light is so slow compared to the
| distances, like, at least several years for a single one-way
| message.
|
| This makes it likely that if we ever do settle multiple stars,
| culture and language will diverge pretty strongly across the
| different settlements, potentially making other, distant humans
| our worst potential enemies.
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