No, the photons also get reabsorbed and emitted constantly on their way up so the ones that have a straight shot out aren't quite the same as they were when they started at the core.

It's technically not the same light as what was emitted in the core, that's why it takes so long. But more importantly the light that gets here is still leaving the surface of the star after having interacted with it, and beyond that there's so much more light that reaches us from the surface directly, that there's no time delay shenanigans. Physicists just say "it takes 1000s of years for that light to reach the surface" as a shorthand for "the electromagnetic energy on an escape vector from the core of the star is emitted as a photon, and over 1000s of years of being transmitted, absorbed and re-emited the energy finally escapes as a photon from the surface."

Good question tho...

There isn't really much going on in black hole collisions. Just spacetime swirling around. Now neutron star collisions on the other hand... There's actual _stuff_ in there.

thats the best place to be. if you knew everything he was saying then you would not be learning

Wikipedia helps a lot, too. If you hear a term you don't understand, wiki it!

there are probably energy differences

They do that already.

The energy and arrival time give some information

Comprehending how much potassium it would take in order to derive 70,000 tons of it at less than 100° Kelvin temperature.., at God knows what pressure it would always need to remain at.... Really feels almost uncomprehendible no matter how you overthink it. And let's not try to figure out the maths of how expensive one cubic foot of liquid argon gas works out to be even when buying in bulk - especially when you're extrapolating up from one cubic foot up to something like 70 billion grams of liquid argon gas approximately/

Argon makes up 1% of the Earth's atmosphere. So it is hardly "super rare."

She is now a professor at a prestigious university.

Light can bend space time yes. And no, this is not taken into consideration because light density is tiny compared to matter. Dark matter outweighs the effects of normal matter by orders of magnitude, to have enough light to replicate this every star in Milky Way would need to be as bright as a small supernova...

@@KuK137 thanks for the reply

Yes they did that. I think that's how they figured out netrinos changing into other type of neutrinos.

There were three different measurements from three different sites.

SNO is still working. It's just not a big detector and will therefore see few neutrinos.

Eventually

@@drdon5205 Awesome. I have an 8 year old special needs child who is absolutely looking forward to it. He watches all of your videos... not sure if he understands it all, but he watches and points out the building every time we're on Roosevelt passing by

In principle, yes. Depends on the specifics of the detector

Yes, they detect all kinds of neutrinos. But, the majority of neutrinos are electron neutrinos.

Yes, many of the current neutrino detectors (including at least most of the ones described in the video) can tell the direction the neutrinos came from, by seeing which way they induce Cerenkov radiation and/or particle showers (the latter for highly energetic neutrinos). I don't know how good the resolution is -- in the comment sections of some other videos, I had thought maybe we could use these to image the neutrino emission of supermassive black hole accretion disks, but some people responded that this is way too optimistic with our current neutrino detector technology.

@@Lucius_Chiaraviglio Thanks mate, I just watched a PBS spacetime video that suggested exactly the same thing. (It has been a four hour rabbit hole and counting) The title was mapping black holes by catching neutrinos, released about a month ago, if you are interested.

@@spindoctor6385 This one? kzfaq.info/get/bejne/edqddb1euJi2Y2Q.html

@@Lucius_Chiaraviglio Yeah that is the one. Sorry I messed up the title a little.

That is a definite maybe. It all depends if the neutrinos interact with the liquid. And that is a big if.

Yes. Since even the Earth doesn't block neutrinos, they have to get some idea of where the neutrinos are coming from to make sure that they are looking at the neutrinos they want to look at.

Pretty much, if you are close enough. Edit: the supernova 'lethal distance' estimate is 50 light years.

Its not that simple after all massive stars form first within giant molecular clouds and these short lived stars supernovae are largely responsible for seeding additional star formation in the same complexes by compressing the gas and dust. For life to get instantly annihilated the supernovae would have to be pretty close astronomically speaking and most such massive stars don't get to wander far from their birth clusters, only the lowest mass stars capable of going supernovae and or high speed run away stars get to escape. As such most of those nearby systems are still in their early stages of formation much like the solar system was when the fossil radioisotope chemical signatures found in asteroids/meteorites were created some 4.5-4.7 billion years ago(In this case I'm referring to elements still chemically bonded like another element that has since decayed rather than like their current element). Clearly that wasn't an endgame for life in our solar system so I wouldn't count out other stars either yet. After all without supernovae guts we wouldn't be here either! ;)

@@Dragrath1 The current estimate, which they call the 'supernova lethal distance' estimate, is ~50 light years.

@@sophiophile Yep cosmically that is a "tiny" distance. ;) The point is that supernovae have pros and cons for example there is work to suggest from a global spike in cosmogenic radioisotopes in sediments of 2.6 million years of age indicating a nearby supernovae (~150 ly or so) that coincides with an interval of climate change and overhaul which based on fossils we know is also largely responsible for driving our evolution as a species. Thus its quite possible that we as a species can be said to owe our existence to that supernovae. Also don't forget that phosphorus (the only cosmically rare element used in disproportionately high amounts by life on Earth) is only produced as a byproduct of oxygen core/shell burning which only occurs in the las few years of a very massive star's life as oxygen burning is the second to last major reaction to produce more energy than it takes to produce it, the last reaction of course being fusing silicon into iron. Such stars will invariably go supernovae unless they collapse directly into black holes and thus the only ay to get phosphorus out into the winder universe is via supernovae. ;) Creation and destruction are intimately linked in our universe by well effectively by the 2nd law of thermodynamics a.k.a. its deeper roots in information theory

@@Dragrath1 Yeah, essentially everything heavier than iron is from supernovae (and/or part of the decay chain of the elements created). Supernovae that result in a black hole collapse also includes an explosion just the same.

Them too.

Night is darker than day because the *by far* brightest object we can see in the sky is our sun. At night we can not see the sun, because the earth is in the way, so it is significantly darker.

Yes.