4:07 That´s not how probability works, and you know it.

Also if you are hit with Gamma ray you turn green if you get angry.

So, Charlemagne experienced a gamma ray burst? ... Awesome.

Q: If a gamma ray burst happened yesterday, and they occur on average every million years in our galaxy, how likely is it that one will happen tomorrow? A: Exactly as likely as it was yesterday.

I got 9999 years of problems but a gama ray burst aint one

Dear youtube, please stop putting comments complaining about the perfectly understandable host above the actual interesting scientific comments ;) Kthxbai

don't know why people complain about her hand movement so much. if anything, some of the other hosts on this channel move their hands way more, and nobody gives them shit

Interestingly enough, there are multiple papers that have come out since this video that state that it was a CME event (larger than the Carrington event by a long shot), from the C14 levels that shot up in trees from the time, and in multiple places around the globe. Were it Gamma rays, it would come from one direction, and not involve trees on the other side of the planet just as strongly, if I read the papers correctly.

From a Journalistic standpoint, I would be interested to see some SciShow Space episodes where the two hosts trade off between jump cuts. I absolutely love both of the Hosts, but I think it could be even better if you were "Trading Off" between segments.

The Anglo-Saxon Chronicle reports a red crucifix being seen in the sky sometime in 774 or 775 CE. Looks like somebody did see this GRB.

ok i've noticed this a few times. where your presenters say something like "if a gamma-ray burst did happen to graze earth 1200 years ago, at least we don't have to worry about it for another 999,000 years or so." but this is so misleading. Some events, like the earthquakes on the Cascadia subduction zone, are fairly regular and happen roughly every X years. but events like a gamma ray burst, or a flood event, or whatever, don't work the way that you imply.. Take a 100-year flood event. You can get several years in a row or several years in a decade which are "100 year flood events" most hydrologists would prefer a term like "100-year recurrence interval." because you are talking about the statistical pattern over 100 years.. the gamma-ray burst is a kind of 1,000,000 year flood and could as easily happen tomorrow as any other day. another way to think of it is the rolling of a die. Every role, the chance of getting a 2 is 1 in 6. every time. just because you get a "2" this time doesn't mean you won't get another 2 until 6 rolls have gone through. so for gamma ray bursts, every year there is a 1:100,000,000 change it will happen this year.

Excellent vid with great content as always. :-) You are one of my favorite hosts :-)

Keep up the great videos!

Found this while looking for a quick explanation of GRBs because I like to remind people that, tomorrow, we might all be dead (especially when arguing with people who think the word "might" carries as much weight as "probably."). Did NOT know about 775. Great, I already suffer from insomnia. Thank you for giving me something to keep me up at night.

Dammit space, every time I feel somewhat safe, I hear about primordial black holes, or asteroids we're really bad at tracking, or the Great Attractor, or some other terrifying apocalypse scenario. Yay science!

could you do an episode about the physics in the movie _Interstellar_ ? :)

Well, I can scrap that from my list of "awesome ways to die". Thanks for the info! ^^

Damn Caitlin, I didn't know you were a crip! Just kidding keep up the good work!

i wish you did more videos

"God smited my sheep" would probably be the response.

Please do not teach people that just because something happens "on average every X years" there are always X years between the events, that's just plain unscientific. If you wanted to relate the likelyhood of a dangerous GRB hitting the earth you should compare it to the viewer winning some sort of lottery (I don't know how the odds compare though)

There was a scishow space video that i was looking for, and it was about some satellite that was monitoring some far away object to see if 2 different types of rays would get back at different times or something like that. In it, there was footage of some woman in her office, and not only the usual hosts. Anyone know which video that was?

Future space weapon....

That's actually a little scary. It means every million years or so the galaxy effectively becomes a shooting gallery where luck dictates which planets are left alone. Yeah I know it is unlikely that a planet will be hit and it needs to be very close to cause substantial damage but still

well heck I don't remember a grb in 775.. but you can check my rings.. I do remember the other one in 1054.. I was having my horse cleaned at the horse wash... wow it was something too.

Nice intro!

I liked this video just for the add that played before it

Disclaimer: this is not a rant, it's rather a PSA. I don't expect you guys to get your statistics and probabilities right because almost nobody does; S & P is a tough topic. Anyway: Actually is not like we "don't have to worry about it for 999.000 years or so". Although 1 million years is "the average" or "the expected" time between Gamma Ray Bursts in our galaxy, that doesn't tells us that we shouldn't worry about it in the 1 million years after a burst. First of all, it's an average. A thing that you obtain summing up all the possible times multiplied by their probability to happen. It tells you about the arbitrarily-long-term common behavior, not anything about what should happen in "this case" or "that case"; nothing at all. The second thing is that the time between bursts is almost certainly distributed Exponentially, which means the time before the event "doesn't have memory". This means that the situation now is not different from the situation in 10.000 years from now. It's not like the bursts will eventually come: it may perfectly happen that they may never come, and you don't change the situation by waiting extra time. BUT it may happen anyways, because the probabilty exists. It just forgets any past event or waiting times.

"Hulk spit on your puny gamma rays . . . wait . . . "

everyone always references satellites and phones, but we'd be out pretty much everything. Same scenario applies to a big enough solar flare. Any fuel injected car relies on separate engine and transmission computers to run. So, unless you're one of the people with a very classic car, you're out transportation too.

I hope this makes sense..: Would the electronic devices frie if turned off?

I don’t think that is how probability works at 4:08. it’s just as likely to happen irregardless less of when it last happened. thanks for the video very interesting

Thank the universe for the inverse square law ... or we'd all be crispy critters.

i've been accused of having "short bursts"

Space is my favorite!!! Especially all those cosmological objects out there. Magnetars, pulsars, neutron stars, black holes, and regular stars. We should try to make some neutron matter, it would take as many neutrons as are in a mountain to make just a pinch of the stuff, but man would it be cool! Just use Mount Kilimanjaro, once removed storm clouds will be able to make their way past, and reclaim some of the desert. Synthesizing neutron material on earth would be a great accomplishment than landing on the moon. WOOOOOH neutron star collision!

cooooooool

Knowing our luck, Gamma-Ray Bursts would be like buses, none are around for what seems like millions of years then two come along at once.

Some long GRB's last several minutes. Also, "very narrow" could mean several earth radii wide.

Well two could happen back to back, but eventually it ratios out to one in a million.

Statistics don't work like that. And secondly there was at least another GRB in our Milky Way as recent as December 27th 2004. At 1.300.000.000.000.000.000.000.000.000.000.000.000.000 Joules and a range of about 50.000 lightyears, it was luckily for us, relatively weak as GRBs go and far enough away. That's about enough energy to heat the world's oceans by 1.000.000.000.000.000.000 degrees Celsius/Kelvin. It was the week I started working in Astrophysics, and the numbers just boggled my mind.

What a crazy video! Gamma Ray Bursts! I'm glad it wasn't worse. I'm going to file this cosmic event under, "Glad I don't have to worry about this everyday" Right alongside, "Sun Engulfs Earth"

OMG SUPER SMILEY LADY!!!

Does this lady ever blink?

I didnt knoww scishow was rolling wit da crips

Watchable!

Whoa, she looked a lot different back then.

gamma ray burst changed my dna

4:10 that is not how probability works. Its just as likely to happen now as it would be without earth ever beeing hit by it.

Maybe the gamma ray hit earth at night when everyone was asleep And whom ever say it and told the others they thought he was crazy

Do more of the Historical videos

there's a horse out there missing its teeth

4:07 : Logical fallacy, probabilities just don't work that way, it has as much chance to happen right now than in 1,000,000 years.

4:12 I thought probability did not work like that!!!

Ok, what happened to the sound from 3:00 - 3:08 ??

Or the wrong place at the wrong time...

She's like that guy who dosent blink from that episode of icarly were he has a world record of not blinking

Hm.. I'm not sure but even if statisticly speaking the event of a gamma ray burst happens everey 1.000.000 year, does not make the chance for it NOT happening tomorrow less, even if it the last time it happened was 1200 years ago? Or am I totaly wrong about the math here?

"Gamma Ray Burst" sounds like the name of a 1980s hair band.

Yah so what? Come at me universe, bring it on. I'll just gather my gang and we'll take you down. lol. My Scooby-Doo gang,

The funny thing is even if a gamma ray burst happened right at this instant inside of the "death zone" it would take 3000 years for it to hit us anyway. By that time we will probably have left earth since the resources we have wont last another 3000 years let alone another 200 if that.

I remember about a year ago that a video hosted by Hank reported extremely powerful gamma ray bursts being detected unexpectedly, and mysteriously, frequently. Does this discovery tell us much about that?

I wouldn't mind the power grid going down for a few weeks. We would all be able to see what the night sky is supposed to look like.

4:13 that's not how stats works. Another GRB is just as likely this year as it was in 775, the odds are just one-in-a-million per year (independently of previous years). BTW maybe you (or the regular Scishow channel) should do an episode about statistical misconceptions - or maybe even about scientific methods and statistical inference.

I enjoy the fact that they explain how scientists figure these things out. Most shows just tell what happened without explaining how. Keep up the good work guys!

Revolution reference :D

Well, if we can't have Hank, at least we have some eye candy. Woot woot

I'm not convinced that there are only 3 possible explanations. What about a miniature black hole explosion as predicted by Hawking and Ellis? That would not necessarily produce a huge amount of visible light and most likely a huge amount of gamma. There is also the weird and wondeful theory that under some conditions uranium in the earths core could pool to the point of achieving critical mass (very unlikely but not impossible). Thats 2 more to get started with.

Is there any way to deflect a gamma ray burst? I'm guessing no because it's made of photons not charged molecules?

A NEUTRON STAR COLLISIONNN

i didnt know caitlin was a crip lol

What's with her hands? Is she conducting an orchestra or landing a plane?

okay, she's adorable

@EdwardLong the molecules have three oxygen atoms, hence "triple oxygen molecules" the triple oxygen phrase describes the molecules.

lotta 'ifs' 'maybes' and 'potentiallys'

GRB= humanity reduced to: "WE LIVE, WE DIE, WE LIVE AGAIN!!!"

She is cool :D

There was one Gamma Ray Burst that lasted 20 hours and destroyed all the theories of the scientists. Quite recently.

This might be a dumb question but aside from the practical limitations in terms of the energy required to produce such a wave, is there no theoretical limit to how small a light wave can be? Is it just the diameter of a single photon?

All power to forward shields

775 is also in the period of the dark ages. Much of history was lost in the dark ages bc of mass famine and plague and lord only knows what else. So maybe it was seen but not cared about bc you or your loved ones were dying of the bubonic plague. Or you didn't have food so you could care less to stay up and watch the stars. While it is very possible bc it was so short that it was missed I think any of these could also explain why no one seen it

There's a horse out there missing its teeth.

You should talk about the Hydrogen Bomb of 1962. The First and Last Nuclear Bomb to ever explode in Space.

Can you do a show on space garbage? I've heard that one of the reasons we don't go to the moon is because of the dangers of space garbage.

wooww!!! less than 3000 light years!!!!!!!!!! damn it's difficult to conceive the power of these gamma rays!!!!!!!!! that's just crazy!!!

We don't have to worry about it for the next 999,000 years or maybe in the next ten minutes. Such is statistics. But I'm sure you know that and it was just a joke. Your arm waving thing reminds me of how a Japanese scientist might have programmed a robot to make it appear more human but actually falls right into uncanny valley. It's seems to be a Sci-show thing. But you are much too nice to be a robot and thanks for all the interesting stuff! Keep 'em coming.

That bandana game

What is the margin of error of that timing?

I noticed you speak a little slower, now I can follow easily! Good job! Also, don't mind the mean comments on youtube, because you know: it's just youtube. Stupid people interested in stuff but not really understanding it, when asked to repeat it...

So there was one observed all over the world a few hundred years before this thing may or may not have hit us? Could it be the same event? More specifically, Was the one that was observed the right distance away to hit us with a faint gamma ray burst a couple hundred years later?

Perhaps the GRB hit the Pacific Ocean, only slightly affecting Japan and the Antarctic but mostly hitting the ocean area. So not many would have seen it

Captions would be appreciated

That's relatively short in space time..

that's not how odds work. just because something tends to happen in pattern, doe not mean it's absolute. we still technically have as high a chance of being destroyed as at any time.

The intro is a bit loud relative to the volume of the host's voice.

Well, if did get hit by a Gamma Ray burst, then we all would've turned in to Hulk's by now. Duh!

How many written records are there from 775 AD to determine if this event - if it even happened - was visible, or created any noticeable effects? And if the only such records are from Europe, and if the gamma ray burst struck only the other side of the earth for a few seconds, then nobody in Europe would've seen it anyway.

Of course, over time (ok maybe a long time to come like a billion years) the instances of supernovae should reduce as all of the stars capable of supernova go ahead and do so. Less of such stars will come into existance in the future.

"On the bright side"

Crazy question, How do we know the source of the gamma radiation came from space?

Based on the information she provided; the solar event from our sun is far more likely to be the cause.