It's strangely comforting that, no matter how bad things get here on our little rock, everything will eventually be laid to waste by some unavoidable cosmic catastrophe.
Don't worry, this elevator has a governor. If the cables break, the governor will hold it. On another note, I should tell you that broken cables plus a failing governor will make your problems go to waste. It will all end for you in less than a second. :P
Kind of like that ending in the muppet movie from 2011 or 2012 where they miss the deadline with their fundraiser, and then they realize they forgot to put in the decimal place and they actually missed the goal by more than a factor of 100, and one of them says "that actually makes me feel better about it, instead of just barely missing it".
No problem, all my displays are LCD, LED-LCD, or OLED. Now, seeing as how the VP is such a VIP, shouldn't we keep the PC on the QT? 'Cause if it leaks to the VC he could end up MIA, and then we'd all be put out in KP.
But, my wife has a thing about having a roof. Is not me, I'm completely open to the idea of living in the box. But, ya know, gotta keep the wife happy.
No it's much worse than that I missed calculated, we have just 35 million years left, it's every 100 million years that a monster asteroid smashes into Earth, the last time this happened was 65 million years ago, the next one could even wipe out the Crocodiles! so save your Crocodile handbags and shoes they could be worth a million times more than what you paid for them
Hmm.. Well, there could be a very small chance that the planets align and may provide protection I suppose. From partial due to the moon, to our usual big brother protector Jupiter. To even Sol, our sun. They've been helpful over the course of the solar system's life in protecting earth from various impacts. Though, to be honest, I still wouldn't count on them to be in the right position to protect us from a GRB.
I've always wondered if a local GRB could have caused massive changes in the composition of the early atmosphere, so that what we believe was a gradual change could have been an fairly abrupt change.
I am thinking the exact same thing, a GRB close enough could strip off a big chunk of the atmosphere massively changing it. It could solve the mystery of the Faint Young Sun where by all rights Earth should have been an ice ball back in the day, or a hothouse now, but we know that neither is true. If a GRB stripped a big chunk of a previous thick atmosphere this would explain a hotter Earth in the past and the relatively cool one today allowing life to thrive in both eras.
@@1503nemanja It wouldn't strip the atmosphere. It would change the chemical composition and split ozone. That's something we could address with modern tech.
@@mzmadmike it depends on how close it is, I think PBS Space-time did a video recently on the effects of supernovae based on how close they are and if they are pointing their poles towards us (allowing for GRBs) so you can look at that if you want to know more
As I learned from Isaac Arthur's channel, the death of the sun is actually not a serious problem for us if we implement star-lifting--by removing material from the sun (basically by floating mirrors on sunlight and focusing them on the sun's surface to cause ejections of matter which is collected through magnetic fields) we can extend the sun's lifespan dramatically and get all the raw elements we need to build anything we want in the process. And all this is more or less possible with existing technology (don't need any materials or technologies we don't already have access to).
Yeah, as Isaac Arthur said, one thing we should consider when we think about the universe in very large time/space scales, is the existence of intelligent life and possibility that it can affect and alter usually occuring natural processes. If, by some miracle, we survive and continue to develop our technology in the next several million years, we might reach the point when we will be able to do whatever we like with the Sun.
why would the mirrors melt, they dont absorb enough radiation to heat up that much, and the amounts they do absorb they will re-emit it in outer space. they might slightly hotter, but melting is not a real concern. Basically same reason why planets dont melt. or why mirrors on earth dont melt. or why satellites dont melt. or for a fun answer, coat them in mercury, you cant melt something that's already a liquid.
SCANDALOUS!! Matt dropped by the set of PBS EONs earlier today to say hello. Next thing they know their latest Ordovician Silurian extinction event script was "misplaced." Hmmm
(Just as an FYI, I was just giving a brother a hand when he ran into a little snag correcting the spelling of someone else. ;) And I'm pretty sure original poster was just being cute. :) )
Guys I just can't believe the quality of your videos. Its a perfect mix between science popularization and stunning video editing. By far my favorite channel out there ! 10 out of 10
I thought the galaxy collision is supposed to be no big deal because solar systems are so far apart that any given one is very unlikely to come near enough to another for them to disturb each other.
Thought so too. The chances for any single solar system to be affected should be extremely low. And we should know if there is a serious danger well in advance, too.
The orbits of the planets out to Neptune around the sun are unlikely to be disturbed in the galactic collision but the solar system's orbit and "location" in the galaxy certainly will be. Our system could be flung towards the center of the galaxy where it would be exposed to extreme radiation and perhaps even fall into one of the supermassive black holes there. Or our system could be thrown right out of the galaxy into the intergalactic void hundreds of thousands of light years from it nearest neighbors making interstellar travel nearly impossible, even if you had Star trek"s warp drive it would still take hundreds of years to get anywhere). Or it may get lucky and end up with a similar "location" and orbit that it has now but than the sun will go into its red giant phase almost immediately after all of this and destroy all life on Earth if not Earth itself.
Thats a myth, the saying is "they are so far apart they are very unlikley to collide" But, it would be devastating to life For one, radiation, two a star could be ejected out or fall inward, asteroid impacts would be common, given oort clould objects and TNOs are easilly afected by other stars
+Zach Crawford you do realise that intergalatic space still has plenty of stars right? It's just less dense. It's actually possible that up to half of all stars are not in galaxies at all. Our closest stellar neighbour would be around 40 light years away on average not in the range of hundreds or thousands of light years. Even without FTL travel methods fractional light speeds would distort the time of the passengers so much that it would be very possible to cross those sorts of distances.
Well I concede people win lotteries though I was referring to the individual. We don't all win the lottery and so given the astronomical improbability of winning a major lottery for an individual it is quite the waste of time for the individual to devote much time to the consideration of what almost certaintly will not happen.
That's no bad thing; for one the discussion helps outline how LIKELY the outcome is, a good part of this video was a discussion of how likely the GRB was; pre-discussion it might well have been very likely indeed, how would we know? And it's not like these things require a massive expenditure of time and effort; who among us won't waste more time with the Star Wars movies? In the end this si largely for amusement, and who can fault that?
Unlike the lottery we will eventually win/lose. The jackpot(a small planetoid impact) or 2nd prize ( GRB, smaller asteroid etc..) is the question. If our numbers will eventually hit is not in doubt, it is a when, not if.
PBS Space Time, First I would like to say I really enjoy your videos and this one in particular was very interesting. I like that you've incorporated a lot of different fields of science to try to explain was has happened and what could happen in the event of a gamma ray burst! That being said, this is a comment inspired by your very first PBS Space Time video Matt but nobody would see a post on a 2015 video. I have recently been going back and watching older videos. If dark matter makes up such a large portion of the universe's mass, wouldn't it also form black holes? I mean gravity (the curvature of space-time) should work the same no matter if space is being curved by baryonic matter or dark matter right? if it truly does make up 80% of the universe's mass, wouldn't there be enough of it to curve space-time enough for us to see it's effects and therefore it's existence via gravitational lensing? Why don't we see any of these effects when we look at the cosmos? Is it possible that there is another fundamental force that acts on a large scale that we are not able to directly observe and test on our smaller scale? Like hypothetically, if we were on the electro-magnetic scale and everything that governed our world and observations was due to the electromagnetic force, would we even be able to observe the much larger scale effects of gravity in a meaningful way? Or would we simply just be left to conclude that the seemingly unexplained effects of gravity, from our scale, were "dark electro-magnetism"? I might just be over curious but I've always kind of wondered about this topic and could never find the right way to phrase my questions until I watched that video "Does Dark Matter BREAK Physics?". Anyway, I really like your videos and I would really appreciate a reply so I can expand my knowledge! Thanks!
I love this channel. I can't get enough. Please do an episode on Interstellar by Christopher Nolan. I'd love to hear your commentary on its marriage of astrophysics and paradoxes while still managing to tell a very compellingly human story.
How tightly focused are the rays from a GRB? I expect the cone would widen with distance. So assuming WR104 fired that bullet that we might dodge, what would the area of it's death ray be when if reached us?
The beam is very, very narrowly focused, moreso than a lot of our lasers. But given the immense distance it spreads out considerably by the time it's moved a few light years. We don't know the precise details but around 3-20 degrees is a good estimate, so a burst 20 ly away may well be several light years across or maybe jsut as 'narrow' as our Oort cloud. (See for eg, page 21 here: www2.astro.psu.edu/users/nnp/araa_pm.pdf )
Spread increases with distance traveled. Since we are considering events up to 10k ly away, that's pretty narrow focus right there. I doubt any laser we could even theoretically build right now would be even detectable at that distance, let alone held to a spread of a few degrees
@PBS Space Time Has anyone managed to detect the signature of an exploding star prior to the obvious burst of light?? Would we be able to look for these signatures and then calculate how long it would take for the GRB to get to us? If it was aimed at Earth?
We've managed to detect the emitted neutrinos at about the same time as the light, indicating that said neutrinos travel at near light speed. Aside from that there's not much else to detect. Our best bet would be to try and work out if there were any obvious visible cues, such as a certain pattern of dulling and brightening. With any luck that could give us weeks or even years of warning.
+ Omar Abdelghani You are absolutely right, and at the same time wrong. Neutrinos don't interact much with common matter, while light does. This means, that although both move at the speed of light, neutrinos could be "faster" and arriving earlier, because light takes a longer path (due to the interactions. That's the reason, why a photon that has been created at the center of the sun takes a million years to reach the sun''s surface and another 8 min from there to reach earth, while neutrinos arrived roughly 1 million years earlier.
Don't neutrinos actually move slower than the speed of light, and just happen to arrive before the light when the explosion happens close enough that light doesn't have time to catch up?
Omar Abdelghani Frank Schneider I am not talking about the Nova event itself. Let me equate this to a volcano on Earth. Along the Pacific Rim we see the magma chamber growing in all of these known hotspots. Since Mount Saint Helens we have been better able to describe what the volcano looked like and how it behaved seismically before the actually explosion. I am asking, have we been able to study massive stars that eventually went Nova to learn what other signatures these starts give off 50/100/200 years before the actual Nova event. If so, we could see these signatures in the sky and know that a Nova event is following them X years after that signature change.
GRBs happen when a black/white hole sucks in an entire star and shoots all it's light directly at us. Think Einstein-Rosen Bridge where the ass end is pointed right at us. We can't see/detect gamma ray bursts that are not pointed directly at us. The video does a great job of explaining the inverse square law of light. (The principal holds true for gravity and electromagnetism.) When a supernova occurs, the light is dispersed in all directions more or less equally. As that light expands outward it gets more and more diluted, as if it were trying to fill up the entire Galaxy. A gamma ray burst is shot out in a very narrow beam in only one direction. The inverse square law of light doesn't apply. That is why they appear brighter than the entire universe.
okay so if our galaxy rotates, is there any chance those mass extinctions happened when we were at a certain location from said spin of the galaxy(I.E. the far right side of the galaxy)?
Our solar system has been around ~21 times, so I wouldn't think it's tied too closely to an arc of the Milky Way. Plus the other stars are spinning too, so they'll shift in location. I think the idea of a danger zone in the rotation is cool though.
Richard Muller was asked to come up with plausible ideas that fit the pattern. He saw they fit a pattern of extinctions approximately every 30 million years, but not always happening. A danger zone every 30 million years. I'm pretty sure he considered what you are suggesting, from many different angles. In the end his suggestion as the most plausible single astronomical cause of these regular mass extinctions was a dwarf star in a binary orbit with our own star, sometimes coming in close and throwing lots of Oort cloud comets about. These days it's considered very unlikely or pretty firmly ruled out, I think. (See the 'Nemesis hypothesis')
So what would happen if the sun is inbetween us and the GRB? Would it be able to shield us from the burst with its huge size and mass or would the GRB just pass through it and still fry our atmosphere?
It would provide a perfect shield. Sadly it'd need to be lined up perfectly to do so, directly in line. In fact we know of no GRB-able stars that are so perfectly aligned.
One of my favorite solutions to the fermi paradox is the idea that GRBs have been becoming increasingly rare since the beginning of the universe due to stellar evolution and the creation of metals. If GRBs used to frequently scour most life from the surfaces of the vast majority of planets then there just might not of been enough time between GRBs in the majority of the galaxy for intelligent life to of evolved. Or to evolved and then develop the technology to spread beyond their planet. Which if that's true it might go a long way towards explaining why we don't see any obvious interstellar civilizations out there. But then you have to ask the question "why are we early?" Our species being one of the earlier ones in our galaxy to become sentient and technologically advanced is presumably a very statistically unlikely thing to of happened.
ApplesPapples Statistically unlikely doesn't mean impossible. If there were to be a few thousand intelligent species during the lifespan of our galaxy, well, someone had to be first. It's also pretty unlikely for Earth to have a huge, dwarf planet sized moon but here we are.
How would a GRB affect a space faring civilization? Would everyone outside the Earth's atmosphere be toast, or would the shielding needed to survive cosmic rays and CMEs be enough? If future Earth is dependant on space resources (asteroid mining, orbital solar power, etc.), and all that support structure disappears (people and electronics getting fried), that would be one more problem to deal with, on top of the impending ice age and the extra UV radiation.
The actual burst isn't too bad, radiation-wise. Any spacefaring civilization, even an intrastellar one, should have some means of shielding and a wide enough spread that the initial burst would be treatable. Worst hit would be a budding civilization,one that hadn't perfected keeping living creatures alive in space long-term. Such a civ could use unmaned and poorly shielded constructs and THOSE could be hit very hard indeed.
Hi! You mentioned stars that between galaxies. Are there estimates on how many solar systems there may be outside of galaxies? They should be rather well protected from gamma ray bursts due to the lack of stars in their neighbourhood?
So how do we Solexit our sol-system out of the Milkyway? Would we just have to decelerate the sun and move it out of the plane of our galaxy to take all of the planets with it? #thoughtExperiment
Interesting followup to solar systems being flung out of the galaxy. Are we able to (and if so, have we) detect stars in intergalactic space. Obviously we'd likely be limited to nearby the Milky Way but I'm intrigued to know if we can. Further related note, what's our actual current maximum range in being able to detect an average star (as opposed to highly energetic phenomena such as pulsars, novas etc).
That first minute was kinda depressing. I'm going to go over to Isaac arthurs channel and listen to him talk about those thing in a much more positive light.
That was an interesting video, and that tech is within the realm of known science, just requires us to build a dyson swarm with mirror satellites to reflect light back in a certain way to cause some of the sun's mass to eject. We should be there in a few centuries.
Idk if he's gonna cover it. Looking around. After watching a few space videos and birth of the earth. Was the Cambrian explosion ended by gamma ray burst?
Don't worry, the Universe is coldly hostile to foolishness. You can't bully, bribe, imprison, deport, or tax the laws of physics. Every billionaire oligarch currently teabagging the dying body of Planet Earth has to eat, breathe, and excrete just like every other life form, and they'll get what's coming to them the same as the rest of us. I look forward to mouth-breathing subnormals running around with MAKE EARTH GREAT AGAIN hats, screaming and hooting about the lib'rul bias of the Universal constants as the ecosphere collapses around them.
Venus is already cloudy with a huge albedo. Also there's next to no nitrogen and no oxygen in Venus' atmosphere. Perhaps a GRB could rip a few CO2 molecules apart and result in slightly more CO molecules. So, no, a GRB is going to do squat for habitability on Venus.
+craIG147680 Venus is simply too hot, and as time goes by, the energy output of the sun continuously increases. So: no. If you ask, because of the GBR "cooling effect": Venus has a completely different atmosphere than earth, no O2, but a lot of CO2. So, this doesn'tz apply and therefor: no. To make Venus more habitable, would need to tug her into an orbit further away from the Sun, eg somewhere near mars orbit or so. Due to the high CO2 content that might be quite comfortable, but this still doesn't solve the problem of sulphuric acid rain.
Is this going to be a new series? If so, would you also consider talking about the False Vacuum Decay hypothesis, even though it's probably the least studied idea of a catastrophic cosmical phenomenon? The video kurzgesagt made about that is a nice introduction, but incomparable to the depth you would provide :D
One more thing I want to add, I am not grad student or a Phd, but I am very actively learning every thing I can in the final years I have been given in life. I know you can't take it with you, but I do want to know. Actually I don't want to know everything, I just want to understand it. That's my opinion and Im sticking to it. Stay healthy!
Don't worry about gamma ray bursts destroying the atmosphere, everyone. My fellow Americans have pledged to do that by 2020. (Please help us, we try to stop them, but we can't.)
I would prefer if you guys at PBS used the proper term "core collapse" instead of collapse. The relatively tiny core is the thing that collapses (NOT the whole star), rest is blown to kingdom come.
Thank you. He said collapse and then showed a graphic of core collapse, which is an annoying inconsistency at best and potentially very confusing at worst.
I'm pretty sure I've heard a solution proposed elsewhere. We can't stop the GRB, but you can avoid it or block it. For instance, an advanced space-faring civilization could use a shkadov thruster to move either their star system, or the threatening star. Or, you could just put a large slab of metal between Earth and a potential GRB that can either reflect gamma rays or absorb them.
As usual, a great and very informative video. Can you do an episode on the difference in the preexisting conditions for a Type II Supernova, Type Ib and Type Ic. And since you're at it include the pair instability ones too.
Don't worry, memes are not nearly as sensitive to UV as phytoplankton. In fact, if we get hit, we'll make just the dankest of memes about dwindling food stores, upsurge in skin cancers, colder climate and the like!
no doubt about that, just makes me realize that everything will eventually fade away; even if we arent going to be around to see it. cant imagine a universe in total darkness, if that makes sense. kinda hard to imagine.
We can'be sure about the future...PBS' view of things is rather negative;I'd recommend you to watch 'Civilizations at the end of time'' here on Yt ^~^. Just think about the scale of the things he said;500 millions of years,1billion years...we could raise a type 2~3 civilization with this much time.(If nothing goes wrong ofc).
We've cast the gods of old aside and created are own and behold, its name is Google. Fitting name considering are god is only a infant. Come join us Thurman and squint into the light
It's strangely comforting that, no matter how bad things get here on our little rock, everything will eventually be laid to waste by some unavoidable cosmic catastrophe.
Yeah it comforts my anxiety very nicely. Lol
I like to think of it as a fresh beginning for little old Earth once in a while.
Don't worry, this elevator has a governor. If the cables break, the governor will hold it. On another note, I should tell you that broken cables plus a failing governor will make your problems go to waste. It will all end for you in less than a second. :P
Kind of like that ending in the muppet movie from 2011 or 2012 where they miss the deadline with their fundraiser, and then they realize they forgot to put in the decimal place and they actually missed the goal by more than a factor of 100, and one of them says "that actually makes me feel better about it, instead of just barely missing it".
You don't know what powers you posess, human. Wait and see, so that awe may fill your heart.
Thank you for the clearly enunciated descriptions, and for keeping the real science in it, not dumbing everything down like we so often elsewhere.
This is one of my favorite episodes in a while. Much more digestible.
A GRB is gonna ruin the RGB calibration on your CRT.
No problem, all my displays are LCD, LED-LCD, or OLED.
Now, seeing as how the VP is such a VIP, shouldn't we keep the PC on the QT? 'Cause if it leaks to the VC he could end up MIA, and then we'd all be put out in KP.
I gotta go reinforce the B.L.T. drive on my C.O.M.P. or it will go A.W.O.L.
Damn, I was going to go for a RGB joke aswell but you already nailed it :D
I don't remember having seen the same user with two top comments before. Props.
OMG
On the plus side, no more student loan payments.
Waltham1892 lul
Interesting offer, but....
Waltham1892 but??
But, my wife has a thing about having a roof.
Is not me, I'm completely open to the idea of living in the box.
But, ya know, gotta keep the wife happy.
No more small talks with the people you dont care about.
Either that, or we end up with a planet full of Hulks.
Can I be Java the Hulk?
More like the ones that aren't the hulk
I choose to believe that.
Message.
I mean, we already did geoengineer the atmosphere, not on purpose though
over 50 years in the wrong direction, wed have 2 years, were fucked. nice joke though
@@Charliepinman Oh no this is the last year, wanna sell me all our stuff real cheap? It's not going to matter next year.
That graphic of the wolfe-rayet star was mind blowing. So beautiful.
Quick hurry the clock is ticking, do what u gotta do now, we have only 45 million years left
No it's much worse than that I missed calculated, we have just 35 million years left, it's every 100 million years that a monster asteroid smashes into Earth, the last time this happened was 65 million years ago, the next one could even wipe out the Crocodiles! so save your Crocodile handbags and shoes they could be worth a million times more than what you paid for them
array s
Sounds like pain in the ass tbh. I'd probably get bored in the first few thousand years :P
That graph actually looked like we are just about due
Mandrak789 what if we keep reïncarnated 45 milion years long than we are fucked
It could happen any time and there would be no warning.
It's incredible life has managed to endure in one way or the other for this long.
Gives you a sense of peace.
1:30 "Every hundred million years or so, when" THE SUN DOTH SHINE AND THE MOON DOTH GLOW!
and the grass doth grow!
The Unturned look into my eyes and it's easy to see, one and one makes two, two and one make three it was destiny
Tenacious D!
Hmm.. Well, there could be a very small chance that the planets align and may provide protection I suppose. From partial due to the moon, to our usual big brother protector Jupiter. To even Sol, our sun. They've been helpful over the course of the solar system's life in protecting earth from various impacts. Though, to be honest, I still wouldn't count on them to be in the right position to protect us from a GRB.
It was DES-ti-neeeee.
The Milk-Doromeda joke at the end made me laugh
I've always wondered if a local GRB could have caused massive changes in the composition of the early atmosphere, so that what we believe was a gradual change could have been an fairly abrupt change.
I am thinking the exact same thing, a GRB close enough could strip off a big chunk of the atmosphere massively changing it. It could solve the mystery of the Faint Young Sun where by all rights Earth should have been an ice ball back in the day, or a hothouse now, but we know that neither is true. If a GRB stripped a big chunk of a previous thick atmosphere this would explain a hotter Earth in the past and the relatively cool one today allowing life to thrive in both eras.
@@1503nemanja It wouldn't strip the atmosphere. It would change the chemical composition and split ozone. That's something we could address with modern tech.
@@mzmadmike it depends on how close it is, I think PBS Space-time did a video recently on the effects of supernovae based on how close they are and if they are pointing their poles towards us (allowing for GRBs) so you can look at that if you want to know more
As I learned from Isaac Arthur's channel, the death of the sun is actually not a serious problem for us if we implement star-lifting--by removing material from the sun (basically by floating mirrors on sunlight and focusing them on the sun's surface to cause ejections of matter which is collected through magnetic fields) we can extend the sun's lifespan dramatically and get all the raw elements we need to build anything we want in the process. And all this is more or less possible with existing technology (don't need any materials or technologies we don't already have access to).
Randall Stephens arthursday is the best day
Yeah, as Isaac Arthur said, one thing we should consider when we think about the universe in very large time/space scales, is the existence of intelligent life and possibility that it can affect and alter usually occuring natural processes. If, by some miracle, we survive and continue to develop our technology in the next several million years, we might reach the point when we will be able to do whatever we like with the Sun.
How do you find mirrors that dont melt?
@Volume Dealer The mirrors are far enough away from the sun that they don't melt.
why would the mirrors melt, they dont absorb enough radiation to heat up that much, and the amounts they do absorb they will re-emit it in outer space. they might slightly hotter, but melting is not a real concern. Basically same reason why planets dont melt. or why mirrors on earth dont melt. or why satellites dont melt.
or for a fun answer, coat them in mercury, you cant melt something that's already a liquid.
This video makes me want to hug my cat.
Here's another video that will make you want to hug your cat
th-cam.com/video/pqMKq7aiblQ/w-d-xo.html
Not a STRANGE COMMENT at all! 😂
Praise the Sun!
seva809 \[T]/
SCANDALOUS!! Matt dropped by the set of PBS EONs earlier today to say hello. Next thing they know their latest Ordovician Silurian extinction event script was "misplaced." Hmmm
XD
It was an inside job, wake up people
For years now I've looked forward to these weekly videos. I don't know what I would do without PBSST.
TL;DR:
The GRB IS A DEADLY LAZOR
lmao
Actually, if we're going to split hairs like that, it's "laser." But hey, we all make typos. ;)
IMMA FIRIN MAH LAZ0R
Its not a laser or a lazor and it most definitely doesn't type in all caps.
(Just as an FYI, I was just giving a brother a hand when he ran into a little snag correcting the spelling of someone else. ;) And I'm pretty sure original poster was just being cute. :) )
Thanks to this video I've been able to finish my research project for school. Thank you so much!!
... and a happy holidays to you too Space Time. 🤪
This channel is one of the very best on TH-cam (for us nerds).
Have you listened to the sonification of a gamma ray burst? It's like the Symphony of Destruction, but with less Megadeth.
Guys I just can't believe the quality of your videos. Its a perfect mix between science popularization and stunning video editing.
By far my favorite channel out there ! 10 out of 10
It's OK.
I thought the galaxy collision is supposed to be no big deal because solar systems are so far apart that any given one is very unlikely to come near enough to another for them to disturb each other.
Thought so too. The chances for any single solar system to be affected should be extremely low. And we should know if there is a serious danger well in advance, too.
Me too bro...
The orbits of the planets out to Neptune around the sun are unlikely to be disturbed in the galactic collision but the solar system's orbit and "location" in the galaxy certainly will be. Our system could be flung towards the center of the galaxy where it would be exposed to extreme radiation and perhaps even fall into one of the supermassive black holes there. Or our system could be thrown right out of the galaxy into the intergalactic void hundreds of thousands of light years from it nearest neighbors making interstellar travel nearly impossible, even if you had Star trek"s warp drive it would still take hundreds of years to get anywhere). Or it may get lucky and end up with a similar "location" and orbit that it has now but than the sun will go into its red giant phase almost immediately after all of this and destroy all life on Earth if not Earth itself.
Thats a myth, the saying is "they are so far apart they are very unlikley to collide"
But, it would be devastating to life
For one, radiation, two a star could be ejected out or fall inward, asteroid impacts would be common, given oort clould objects and TNOs are easilly afected by other stars
+Zach Crawford you do realise that intergalatic space still has plenty of stars right? It's just less dense. It's actually possible that up to half of all stars are not in galaxies at all. Our closest stellar neighbour would be around 40 light years away on average not in the range of hundreds or thousands of light years. Even without FTL travel methods fractional light speeds would distort the time of the passengers so much that it would be very possible to cross those sorts of distances.
My favourite depiction of this scenario is from "Diaspora", by Greg Egan. It's got some cool software and uploaded people in it too. :)
These discussions are like discussing what you going to do with the money after you win the lottery.
People do win the lottery though. And we can be hit by a GRB. Unlikely things happen much more often then you would first think.
Well I concede people win lotteries though I was referring to the individual. We don't all win the lottery and so given the astronomical improbability of winning a major lottery for an individual it is quite the waste of time for the individual to devote much time to the consideration of what almost certaintly will not happen.
That's no bad thing; for one the discussion helps outline how LIKELY the outcome is, a good part of this video was a discussion of how likely the GRB was; pre-discussion it might well have been very likely indeed, how would we know? And it's not like these things require a massive expenditure of time and effort; who among us won't waste more time with the Star Wars movies? In the end this si largely for amusement, and who can fault that?
So... You are telling me that if earth is hit by a GRB it will die due to hookers overdose?
Unlike the lottery we will eventually win/lose. The jackpot(a small planetoid impact) or 2nd prize ( GRB, smaller asteroid etc..) is the question. If our numbers will eventually hit is not in doubt, it is a when, not if.
PBS Space Time, First I would like to say I really enjoy your videos and this one in particular was very interesting. I like that you've incorporated a lot of different fields of science to try to explain was has happened and what could happen in the event of a gamma ray burst!
That being said, this is a comment inspired by your very first PBS Space Time video Matt but nobody would see a post on a 2015 video. I have recently been going back and watching older videos.
If dark matter makes up such a large portion of the universe's mass, wouldn't it also form black holes? I mean gravity (the curvature of space-time) should work the same no matter if space is being curved by baryonic matter or dark matter right? if it truly does make up 80% of the universe's mass, wouldn't there be enough of it to curve space-time enough for us to see it's effects and therefore it's existence via gravitational lensing? Why don't we see any of these effects when we look at the cosmos? Is it possible that there is another fundamental force that acts on a large scale that we are not able to directly observe and test on our smaller scale?
Like hypothetically, if we were on the electro-magnetic scale and everything that governed our world and observations was due to the electromagnetic force, would we even be able to observe the much larger scale effects of gravity in a meaningful way? Or would we simply just be left to conclude that the seemingly unexplained effects of gravity, from our scale, were "dark electro-magnetism"?
I might just be over curious but I've always kind of wondered about this topic and could never find the right way to phrase my questions until I watched that video "Does Dark Matter BREAK Physics?". Anyway, I really like your videos and I would really appreciate a reply so I can expand my knowledge! Thanks!
Hasn't the presence of dark matter, both around galaxies as well as outside them, been detected precisely by the resulting gravitational lensing?
TiagoTiago that's what I was wondering
IIRC, the Wikipedia page for dark matter has a section about the evidence we've found so far, including gravitational lensing.
TiagoTiago sweet, thanks, I'll take a look!
We need a big umbrella. Like... big.
Hey! Its been 2 weeks since this vid.. possibly longer, since I dont know what day it is. I want my pbsspacetime!
I study paleontology and had a full nerd attack when I saw the video this week is on GRB extinction!!!
Thank you Family that is beautiful, peace and love, Doug:)
Relax, people! No need to lose your sleep!
My mother in law is so fat she can be used as a shield against gamma ray bursts.
OOOOOOOOOOOOOOH
That burn was hotter than the light from a GRB.
wrg, relax nmw
I know your wife and I'm telling her.
mine too! let's have then group up and back out both universal suns!
MusiCanines - The Musical Dogs tysm for calming my racing heart. This had me so scared that I’d loose my phone.
Some might call WR104 a "death star" then?
Damn, it would be neat to have whole episode voiced in Klingon, maybe for April's fools :d?
Nebularium - General relativity and quantum physics explained in Klingon... I can't wait 😊
Matt O'Dowd, you are an excellent teacher.
Starlifting could push our sun's demise back a long way. We've got a long time to do our homework on that one.
jezzbanger And we'll colonize the sun!
I love this channel. I can't get enough. Please do an episode on Interstellar by Christopher Nolan. I'd love to hear your commentary on its marriage of astrophysics and paradoxes while still managing to tell a very compellingly human story.
How tightly focused are the rays from a GRB? I expect the cone would widen with distance. So assuming WR104 fired that bullet that we might dodge, what would the area of it's death ray be when if reached us?
Given that he said that nowhere in the Solar System would be safe then at least as wide as the orbit of Neptune and probably more.
solarsystem.nasa.gov/planets/neptune/facts
4,498,396,441 km yeah thats kind of big
The beam is very, very narrowly focused, moreso than a lot of our lasers. But given the immense distance it spreads out considerably by the time it's moved a few light years. We don't know the precise details but around 3-20 degrees is a good estimate, so a burst 20 ly away may well be several light years across or maybe jsut as 'narrow' as our Oort cloud. (See for eg, page 21 here: www2.astro.psu.edu/users/nnp/araa_pm.pdf )
Gareth Dean I would not call 3-20 degrees "narrowly focused." We have lasers that are WAY better than that, surely.
Spread increases with distance traveled. Since we are considering events up to 10k ly away, that's pretty narrow focus right there. I doubt any laser we could even theoretically build right now would be even detectable at that distance, let alone held to a spread of a few degrees
Who's watching this 100 million years later
Man, you should voice an audiobook
Or maybe be a voice of an extra in a sexualobster video.
I love PBS SpaceTime!
a GRB extinction event would be pretty cool... hehe
Leader of Communist China nooooooooo
BTW...I love your videos and watch all I find. Thank you.
@PBS Space Time Has anyone managed to detect the signature of an exploding star prior to the obvious burst of light?? Would we be able to look for these signatures and then calculate how long it would take for the GRB to get to us? If it was aimed at Earth?
We've managed to detect the emitted neutrinos at about the same time as the light, indicating that said neutrinos travel at near light speed. Aside from that there's not much else to detect. Our best bet would be to try and work out if there were any obvious visible cues, such as a certain pattern of dulling and brightening. With any luck that could give us weeks or even years of warning.
Andrew Frank no matter or information of any kind can travel faster than the speed of light.
+ Omar Abdelghani
You are absolutely right, and at the same time wrong. Neutrinos don't interact much with common matter, while light does. This means, that although both move at the speed of light, neutrinos could be "faster" and arriving earlier, because light takes a longer path (due to the interactions. That's the reason, why a photon that has been created at the center of the sun takes a million years to reach the sun''s surface and another 8 min from there to reach earth, while neutrinos arrived roughly 1 million years earlier.
Don't neutrinos actually move slower than the speed of light, and just happen to arrive before the light when the explosion happens close enough that light doesn't have time to catch up?
Omar Abdelghani Frank Schneider I am not talking about the Nova event itself. Let me equate this to a volcano on Earth. Along the Pacific Rim we see the magma chamber growing in all of these known hotspots. Since Mount Saint Helens we have been better able to describe what the volcano looked like and how it behaved seismically before the actually explosion.
I am asking, have we been able to study massive stars that eventually went Nova to learn what other signatures these starts give off 50/100/200 years before the actual Nova event. If so, we could see these signatures in the sky and know that a Nova event is following them X years after that signature change.
I love this channel, i am hoping you guys see this comment and do show on supersymetry. That would be awesome
Well aren't you just a ray of sunshine at this festive time. A gamma ray that is gonna wipe us out. Lmao great show!
I always giggle when you say Spacetime
Whats the width of such bursts and probability that earth would be in that cone when the star does go supernova? Isn't our solar system also rotating?
up to several lightyears...
GRBs happen when a black/white hole sucks in an entire star and shoots all it's light directly at us. Think Einstein-Rosen Bridge where the ass end is pointed right at us.
We can't see/detect gamma ray bursts that are not pointed directly at us.
The video does a great job of explaining the inverse square law of light. (The principal holds true for gravity and electromagnetism.)
When a supernova occurs, the light is dispersed in all directions more or less equally. As that light expands outward it gets more and more diluted, as if it were trying to fill up the entire Galaxy.
A gamma ray burst is shot out in a very narrow beam in only one direction. The inverse square law of light doesn't apply. That is why they appear brighter than the entire universe.
okay so if our galaxy rotates, is there any chance those mass extinctions happened when we were at a certain location from said spin of the galaxy(I.E. the far right side of the galaxy)?
Our solar system has been around ~21 times, so I wouldn't think it's tied too closely to an arc of the Milky Way. Plus the other stars are spinning too, so they'll shift in location. I think the idea of a danger zone in the rotation is cool though.
Richard Muller was asked to come up with plausible ideas that fit the pattern. He saw they fit a pattern of extinctions approximately every 30 million years, but not always happening. A danger zone every 30 million years.
I'm pretty sure he considered what you are suggesting, from many different angles.
In the end his suggestion as the most plausible single astronomical cause of these regular mass extinctions was a dwarf star in a binary orbit with our own star, sometimes coming in close and throwing lots of Oort cloud comets about. These days it's considered very unlikely or pretty firmly ruled out, I think. (See the 'Nemesis hypothesis')
These ones interest me so much. So awesome.
So what would happen if the sun is inbetween us and the GRB? Would it be able to shield us from the burst with its huge size and mass or would the GRB just pass through it and still fry our atmosphere?
It would provide a perfect shield. Sadly it'd need to be lined up perfectly to do so, directly in line. In fact we know of no GRB-able stars that are so perfectly aligned.
One of my favorite solutions to the fermi paradox is the idea that GRBs have been becoming increasingly rare since the beginning of the universe due to stellar evolution and the creation of metals.
If GRBs used to frequently scour most life from the surfaces of the vast majority of planets then there just might not of been enough time between GRBs in the majority of the galaxy for intelligent life to of evolved. Or to evolved and then develop the technology to spread beyond their planet.
Which if that's true it might go a long way towards explaining why we don't see any obvious interstellar civilizations out there.
But then you have to ask the question "why are we early?"
Our species being one of the earlier ones in our galaxy to become sentient and technologically advanced is presumably a very statistically unlikely thing to of happened.
ApplesPapples Statistically unlikely doesn't mean impossible. If there were to be a few thousand intelligent species during the lifespan of our galaxy, well, someone had to be first. It's also pretty unlikely for Earth to have a huge, dwarf planet sized moon but here we are.
How would a GRB affect a space faring civilization? Would everyone outside the Earth's atmosphere be toast, or would the shielding needed to survive cosmic rays and CMEs be enough? If future Earth is dependant on space resources (asteroid mining, orbital solar power, etc.), and all that support structure disappears (people and electronics getting fried), that would be one more problem to deal with, on top of the impending ice age and the extra UV radiation.
The actual burst isn't too bad, radiation-wise. Any spacefaring civilization, even an intrastellar one, should have some means of shielding and a wide enough spread that the initial burst would be treatable. Worst hit would be a budding civilization,one that hadn't perfected keeping living creatures alive in space long-term. Such a civ could use unmaned and poorly shielded constructs and THOSE could be hit very hard indeed.
Man, this was a nervewrecking up and down of hope and despair :D
Hi! You mentioned stars that between galaxies. Are there estimates on how many solar systems there may be outside of galaxies? They should be rather well protected from gamma ray bursts due to the lack of stars in their neighbourhood?
it is estimated that about a half of all stars are rogue aka not orbiting in galaxies.
So how do we Solexit our sol-system out of the Milkyway? Would we just have to decelerate the sun and move it out of the plane of our galaxy to take all of the planets with it? #thoughtExperiment
google stellar engine....
Got a good source on that? I am curious.
not on hand sadly... I think I've heard it in Issac Arthur's video or possibly SciShow Space...
I really like this episode, thank you
Andromway would probably be a better galaxy name than Milkdromeda. Or we could just call it Bob. Or Mary. The Marybob Galaxy?
Or Andromedaway
We should call that galaxy Andromeda, because it is already twice the size of the milky way, which will simply (at least in effect) be absorbed.
Andromeda's Way
I'll call it Milkadrom
Milkadrome : 2 galaxies enter, 1 galaxy leaves
Gorgeous graphics!
Dang, was hoping I'd turn into the Hulk.
Interesting followup to solar systems being flung out of the galaxy. Are we able to (and if so, have we) detect stars in intergalactic space. Obviously we'd likely be limited to nearby the Milky Way but I'm intrigued to know if we can.
Further related note, what's our actual current maximum range in being able to detect an average star (as opposed to highly energetic phenomena such as pulsars, novas etc).
The "spacetime" pun at the end was a lot more forced this time..
Except they aren't even puns.
Fixed
The "spacetime" pun at the end was a lot more forced this time.. On spacetime
Yeah, I'm getting sick of them.
Does anybody always say it along with him even if you haven't seen the episode?
Thank you
That first minute was kinda depressing. I'm going to go over to Isaac arthurs channel and listen to him talk about those thing in a much more positive light.
Well folks, it’s been nice knowing you. Godspeed
Expanding Sun.
We could mine Sun , and by lowering it's mass making it colder , and stop expanding... (Thx Isaac Arthur)
That was an interesting video, and that tech is within the realm of known science, just requires us to build a dyson swarm with mirror satellites to reflect light back in a certain way to cause some of the sun's mass to eject. We should be there in a few centuries.
Hearing him speak Klingon just made my Tuesday.
Would it be too much to ask to delay your relentless apocalypse videos until after the holidays!!!?
No way I want to get it over with!
He actively avoided talking about anthropomorphic radiative forcing, so Happy Holidays
Well, that was an uplifting and joyful video. Now, if you’ll excuse me, I need to start build a gigantic mirror!
But but but I thought we only have 12 years left because of global warming?
Idk if he's gonna cover it. Looking around. After watching a few space videos and birth of the earth. Was the Cambrian explosion ended by gamma ray burst?
2:30 I have more to look into!
I could really go for an extinction level event right now.
Its known as global warming
thoughtlesskills
I'm down. Learn to swim...
Or you could do it on a mini-scale to yourself first - call it a practice run!
Fuh Q I'll see you down in Arizona Bay.
Don't worry, the Universe is coldly hostile to foolishness. You can't bully, bribe, imprison, deport, or tax the laws of physics. Every billionaire oligarch currently teabagging the dying body of Planet Earth has to eat, breathe, and excrete just like every other life form, and they'll get what's coming to them the same as the rest of us. I look forward to mouth-breathing subnormals running around with MAKE EARTH GREAT AGAIN hats, screaming and hooting about the lib'rul bias of the Universal constants as the ecosphere collapses around them.
You’re seriously my favorite person.
Could a GRB make Venus habitable?
No.
Thanks mate you cleared that right up
Venus is already cloudy with a huge albedo. Also there's next to no nitrogen and no oxygen in Venus' atmosphere. Perhaps a GRB could rip a few CO2 molecules apart and result in slightly more CO molecules. So, no, a GRB is going to do squat for habitability on Venus.
+craIG147680
Venus is simply too hot, and as time goes by, the energy output of the sun continuously increases. So: no.
If you ask, because of the GBR "cooling effect": Venus has a completely different atmosphere than earth, no O2, but a lot of CO2. So, this doesn'tz apply and therefor: no.
To make Venus more habitable, would need to tug her into an orbit further away from the Sun, eg somewhere near mars orbit or so. Due to the high CO2 content that might be quite comfortable, but this still doesn't solve the problem of sulphuric acid rain.
craig147680 This comment made me want to watch Internet Comment Etiquette with Erik. XD
Hot dang, I don't think I've ever been this early!
Love your videos!
really depressing video for christmas
You can resurrect, can't you?
Best explanation of Death Stranding so far!
Keeping an eye on Betelgeuse 😰
That is a Supergiant. Hypergiants the stars that will become black holes that will shoot gamma ray bursts
Is this going to be a new series? If so, would you also consider talking about the False Vacuum Decay hypothesis, even though it's probably the least studied idea of a catastrophic cosmical phenomenon? The video kurzgesagt made about that is a nice introduction, but incomparable to the depth you would provide :D
algiuz I did not know that, thanks! :D
Planet of the Hulks
No
Yes
Let the guy dream.
One more thing I want to add, I am not grad student or a Phd, but I am very actively learning every thing I can in the final years I have been given in life. I know you can't take it with you, but I do want to know. Actually I don't want to know everything, I just want to understand it. That's my opinion and Im sticking to it. Stay healthy!
Don't worry about gamma ray bursts destroying the atmosphere, everyone. My fellow Americans have pledged to do that by 2020. (Please help us, we try to stop them, but we can't.)
8:30 often correlated? I love it
lol, milkdromeda..
Here is also an interesting explanation:
DO EXTRAGALACTIC COSMIC RAYS INDUCE CYCLES IN FOSSIL DIVERSITY?
Mikhail V. Medvedev and Adrian L. Melott
I would prefer if you guys at PBS used the proper term "core collapse" instead of collapse. The relatively tiny core is the thing that collapses (NOT the whole star), rest is blown to kingdom come.
Thank you. He said collapse and then showed a graphic of core collapse, which is an annoying inconsistency at best and potentially very confusing at worst.
I'm pretty sure I've heard a solution proposed elsewhere. We can't stop the GRB, but you can avoid it or block it. For instance, an advanced space-faring civilization could use a shkadov thruster to move either their star system, or the threatening star. Or, you could just put a large slab of metal between Earth and a potential GRB that can either reflect gamma rays or absorb them.
23 and me have openly admitted to altering their results for their own motives.
RaptorBaptist they have?
I never heard about this. And what would their motive be?
As usual, a great and very informative video. Can you do an episode on the difference in the preexisting conditions for a Type II Supernova, Type Ib and Type Ic. And since you're at it include the pair instability ones too.
Oh no!
What about our memes???
Don't worry, memes are not nearly as sensitive to UV as phytoplankton. In fact, if we get hit, we'll make just the dankest of memes about dwindling food stores, upsurge in skin cancers, colder climate and the like!
Memes don't die, they just lose their hype.
One does not simply kill a meme, unless it's normie shit.
A GRB would be the meme of all memes. Just not enjoyed by us.
Well, gamma-ray bursts may explain the Fermi Paradox rather neatly, but I hope that I'm wrong.
All these concepts make me realize how insignificant anything is, makes me wanna throw up
It depends at your perspective of 'insignificant', some people don't care about the universe and are happy bonding with their family and friends.
no doubt about that, just makes me realize that everything will eventually fade away; even if we arent going to be around to see it. cant imagine a universe in total darkness, if that makes sense. kinda hard to imagine.
We can'be sure about the future...PBS' view of things is rather negative;I'd recommend you to watch 'Civilizations at the end of time'' here on Yt ^~^.
Just think about the scale of the things he said;500 millions of years,1billion years...we could raise a type 2~3 civilization with this much time.(If nothing goes wrong ofc).
this was a good conversation, thanks for your time. Not everyone on youtube is as civil.
congratulations for the 1 million subs.
I don't believed this BS...Marvel says we will become Hulk...
Nah; We'll all die because some molecules in the sky change and reflect light differently and shit.
MirceaKitsune
My grandma's umbrella was forged from Captain America's shield...It will protect me from any shit....
Is there any way to block a GRB? Perhaps atmospherically (or using the giant disco ball reflectors you mentioned in your kugelblitz challenge)...
First
But, if NO2 absorbs more light, wouldn't that make the atmosphere warmer?
(Or would that heat remain in the upper atmosphere only?)
The answer to these problems is Jesus Christ bro
Thurman Sherman Ikr, people using Google nowadays when you could use the Bible to find the answers :v
Google's faster
We've cast the gods of old aside and created are own and behold, its name is Google. Fitting name considering are god is only a infant.
Come join us Thurman and squint into the light
Usually I go to nuke vids for a lift but this did the trick.