Dark Matter Evidence, Oort Cloud Shape, Size of Lagrange Points | Q&A 229

Will LIGO detect gravitational waves when Betelgeuse explodes? Why are scientists so sure about dark matter? Could Betelgeuse become a black hole after it goes supernova? Why is the Oort cloud a sphere, not a disk? What determines the size of Lagrange points? All this and more in this week's Q&A!
Dark matter is not a theory
• dark matter is not a t...
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00:00 Start
00:49 [Tatooine] Why is the Oort cloud a sphere?
06:25 [Coruscant] Could field stars have no metals?
11:00 [Hoth] Will Betelgeuse become a black hole?
12:32 [Naboo] Why the Universe didn't become a black hole?
14:45 [Kamino] Why are scientists so sure about dark matter?
20:56 [Bespin] Will LIGO detect Betelgeuse's bang?
25:02 [Mustafar] Will Earth's polarity flip break all compasses?
26:21 [Alderaan] How big are Lagrange points?
28:45 [Dagobah] What science discovery do I anticipate the most?
29:57 [Yavin] Can we safely go through heliospheric termination shock?
32:03 [Mandalore] How big must the accretion disk be for Sgr A* to be visible from Earth?
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[@arnelilleseter4755]

"We don't know" is maybe the most important statement in science. It is also the most honest answer to a question. I wish people would say it more often instead of just making stuff up to make things fit into their worldview.

[@storyspren]

Kamino for sure was my favorite answer. The succinctness of "it's not a theory, it's an observation" is something I've been missing, and the example with the "what's the driver's name" was really funny and as an analogy it keeps getting better the more I think about it.

[@frasercain]

I'm glad that helped. Definitely watch her video too.

[@Skukkix23]

Great to see that Collier gets a shoutout here. Watching her stuff for months now and the dark matter video knocked it out of the park

[@Jarlaxleify]

Great stuff man, thanks for all the hard work. Your passion has taken ours much further than either would have gone on their own

[@frasercain]

Thanks a lot, I'm glad you're enjoying it.

[@thebigerns]

I like the empty refrigerator observation… where did the food go? Did I forget to go shopping? Did my roommates eat it all? Is there a black hole lurking in my fridge?

[@madderhat5852]

There are no such things as refrigerators. 😁

[@anthonyalfredyorke1621]

Another great show Fraser , enjoy your live stream holiday. I know that your still working but I'm selfish, I could listen to your dulcet tones every day. Keep up the good work , I love your interviews . PEACE and LOVE to EVERYONE.

[@McFugo]

Tatooine for sure, it's questions like these that make me go "...huh, I've been consuming popsci media about astronomy since I can remember and I hadn't even wondered about something so logically perplexing." Plus learning that the Oort cloud actually stretches out so far was cool. I have a question too: How do we know that half the galaxies we see aren't made from antimatter? From what I can tell antimatter galaxies possibly look the exact same as matter galaxies, or would they give off some different kind of radiation? Thanks as always!

[@NoNameAtAll2]

telescopes observe no border between matter and antimatter regions (which would've been hot as interstellar/intergalactic gas collides)

[@jesusramirezromo2037]

We know there's no anti matter galaxies because there would be constant anhylation events, as galaxies interact with one another

[@bitflogger]

If humans have colonies mining Oort Cloud objects, finding themselves near the far edge of the cloud, may find that its only a short hop to reach a nearby stars Oort cloud. So going to another star could be a long series of steps.

[@stephenwise3635]

Like stepping stones :)

[@robertnewhart3547]

Then maybe manipulate the magnetic fields between the systems and use it as a conveyor belt. Magnetic rail system.

[@fighteer1]

The Oort cloud is so diffuse that traveling between objects would be like traveling between planets. I'm not sure it's meaningful to discuss "colonizing" it, any more than a single ant could be said to colonize a chain of islands.

[@bitflogger]

@@fighteer1 There may be haphazard opportunities that require planning and knowledge. Didn't the Voyager spacecraft do something similar? I heard a hint of this idea in an Isaac Arthur video.

[@IMBlakeley]

@@bitflogger Voyagers took advantage of a rare alignment of the giant outer planets to do their gravitational slingshots, the Oort cloud is way more diffuse, smaller darker objects separated by many AU.

[@X3MgamePlays]

Kamino I really like the fact that scientist also mention that we might not know how gravity works exactly. I like the exoctic idea: That dark matter is simply matter from a parralel universe. Close enough to have influence on the matter in this universe. And they probably have a galaxy of their own at the same spots. Some larger, some smaller. Thus also explaining how some galaxies seem to contain more dark matter while others seem to contain less dark matter.

[@midnightroadstudios]

I love this channel!

[@StreamHottieSuperSimp]

#me2

[@busybillyb33]

"Zone of Don't Bother" I'm going to use that on a sign outside my bedroom door.

[@chrstfer2452]

Acollierastro is one of the best science youtubers out there. Shes so well spoken, so fackin smart, so freaking charismatic in a quirky nerd way that i love. *AND* shes a whispernet like, founder or something. At the very least a huge promoter/shaper of it, idk if anyone could be considered a founder of a decentralized movement

[@StreamHottieSuperSimp]

Fraser, keep 'm coming. I enjoy rhis channel so much.

[@chrstfer2452]

Wait the oort cloud might extend out *halfway to proxima centauri*??? Holy. Fricking. Shoot. What. The. Frick. Thats wiiiiiiiild! Thats so neat. Our star (and i suppose stars in general hehe, but this one is ours) is so neat

[@BLITZKRIEG1]

🤦🏻‍♂️

[@skarphld]

Tatooine, just barely edging out three others tied for second place. Excellent video. Thank you.

[@R.Instro]

Kamino - You make an incredibly understated, yet important point: even multiple consistent & verifiable observations do not automatically equate to understanding or positive identification; they are a good first step along the path, but not the destination.

[@onebylandtwoifbysearunifby5475]

Croissant. (Close to lunch time.) Plus Field stars are an interesting out-of-sight entity.

[@mihan2d]

[attempt 2] What do we know about the Roche worlds (binary planets of similar mass)? It seems to be an incredibly quirky concept, and still no one mentions it. Can they really share an atmosphere, and if so then if one was to develop an intelligent species would they only have to invent airplanes in order to colonize the sister planet? Does the physics mean the gravity on the sides of both planets would be pointing slightly "sideways" due to tidal pull? Seems like a very underrepresented concept both in sci-fi and in popular science.

[@McBanditHope]

Interesting idea!

[@kevinsayes]

I love learning about the Oort Cloud. It’s mind blowing

[@slateslavens]

Naboo: I forget my black hole mechanics, but one night my daughter and I discussed this very thing. We postulated that a black hole isn't necessarily a "singularity" as it is a concentration of matter that still had to occupy space. Assuming this, our thought was that when the black hole accumulated enough mass that the growing mass boundary inside intersected the event horizon, the black hole would explode in a "special nova". The thought being this (understand this was a thought experiment and no math was actually taking place): Assuming that mass _must_ take up space and that "event horizons" behave as they are demonstrated to, there is a critical limit where the minimum radius of the accumulated mass inside a black hole meets and exceeds the Chandrasekhar Limit. When this happens, the gravitational forces of the black hole are no longer sufficient to hold the black hole together and it explodes in its entirety. What is the mass limit of such a black hole? _Exactly one universe_ You see where this goes, right?

[@jessehavlin1490]

I think this is a cool concept to think about, and probably in some way describes the cyclical nature of the universe (I don't believe for a second that the universe is a temporary phenomenon - it must be cyclical like everything else), but the Chandrasekhar limit is just 1.44 solar masses. In order to be a black hole it has already exceeded that limit. Perhaps there is another phenomenon where a black hole exceeds a certain mass (like you said, all of the mass and energy of the universe) and it results in a big bang.

[@slateslavens]

@@jessehavlin1490 sorry, bad wording in that phrase. by 'exceeding the Chandrasekhar limit', I meant that the radius of the accumulated mass was greater than the radius of the Chandrasekhar boundary.

[@pbourd]

I vote for Tatooine: the Oot cloud shape, cool

[@monkeypuzzlefarm]

Fantastic episode as usual. Thank you!

[@CandideSchmyles]

Someone famous once said "The more I know the more I know nothing". After some 50 years captivated by and seeking out all news on astronomy and cosmology that has become the most profound, perhaps the only 'truth' I know.

[@MBoose69]

Hey Fraser! Excited about the new gravitational wave announcement. How do detectors like Ligo determine the distance gravitational waves have travelled?

[@frasercain]

If you want to hear an interview about what they're likely to announce, check this out: kzbin.infoeF3wt8obkD0 You need to have a visual observation of the galaxy, like when they discovered the kilonova, that allows you to verify the distance using the gravitational waves.

[@KarelGut-rs8mq]

@@frasercain That's not necessary. The periodicity of the waves determine the combined mass of whatever caused the gravitational waves and then you use Einsteins equations for General Relativity to calculate what the strength of the waves should be at source then it's a simple calculation to compare the strength of the waves when observed and that gives you the distance. It's the same method as when calculating distances by using Type 1a supernovas except then the mass is given (thanks to Chandrasekar).

[@MBoose69]

@@KarelGut-rs8mq that makes sense!!! Thank you

[@pauldavis1943]

Thanks for answering my question! Will need to give some more thought to the shape of the ort cloud

[@johndoepker7126]

Can't always catch ya live. But I gotta say, your episodes, are always a highlight. Your topics, guests, and the way you get us, the viewers, involved.......Phenomenal!!! I can't say thank you enough for the work you put into providing us with absolutely awesome content and reporting !!!! Edit: Kamino is much favorite of this episode !!!

[@jaymenjanssens720]

Always looking for more Oort Cloud vids.

[@CodyBrumfield1]

I’m glad you shouted out Angela Colier. She’s the best science communication prospect ever. It’s like when Lebron declared for the NBA draft and everyone was like, “This one is already an NBA talent. Everyone else go over there.”

[@davidguillen6611]

Thank you for yet another enjoyable episode!

[@AstroEphemeris]

14:55 i like how when you mention her, you blush. I noticed a camera shift adjusting. I think shes a brilliant astrophysicist as well, I appreciate her contribution to science and entertainment.

[@lurkst3r]

Dagobaaaaaah! Thats an exciting question to look forward to! So many stars and galaxies, its just a case of "When", not "If"!

[@petevenuti7355]

Tatooine!! I imagine that if i could see the ort cloud from a distance, I would see that it looks like a cell wall, like every star is a nucleus , every star has something like an Oort cloud, but they're not really bound to any one star and all that matter just drifts in the interstellar medium balanced between the Stars!!

[@JimKrause1975]

I love your channel! I love this content!

[@agentdarkboote]

Tatooine! I've always wondered about the oort cloud shape!

[@Pacer...]

Some of the best content on KZbin

[@Fimaniac]

Kamino. ❤ Observations versus speculations. Great to focus on this in our world of misinformation. Thanks Fraser, for your wonderful explanations…

[@teppec]

Mandalore: Kind of a followup using your example, if we were in the middle of the Andromeda merger, and Andromeda's central black hole went active and we weren't edge on, would it be visible to the naked eye at any appreciable distance? Would it have to be pointed relatively in our direction?

[@vishal-singh]

One of the best ones!

[@universemaps]

[Yavin] Great episode as always!

[@cavetroll666]

very good episode :D

[@MCsCreations]

Bespin! About compasses, I already have one that points south... I put it over a small magnet by accident. 😬 Anyway, thanks, Fraser! Stay safe there with your family! 🖖😊

[@JungleJargon]

Philosopher discovered that the universe is not expanding into oblivion for no reason or source of power. It's only the vast distance between galaxies that is expanded because of the lack of matter in the vicinity in our line of sight due to the effect of general relativity. This eliminates the need for dark matter and the vacuum energy of space (dark energy) is associated with black holes that are increasing in size anyway and is unrelated to the expanded distance between galaxies other than perhaps pulling at empty space somewhat.

[@7heHorror]

Tatooine. Splendid set of questions.

[@frasercain]

Thanks!

[@JenniferA886]

Nice job… love all the questions, great channel 👍👍👍

[@user-lo2cs7bs9v]

Kamino was my favorite for sure! Great question and great answer! Thank you. Question: i have recently become fascinated by early space travel history. If you could change anything about the Apolo or Gemini missions what would it be and why?

[@frasercain]

I think the Gemini missions were the perfect template for space exploration. Do a few new things with each mission. So I would have never stopped the Geminis. We'd be up to Gemini 549 by now if it were up to me.

[@nikhansen213]

Great episode! Thank you for creating such amazing content. I was happy to hear you reference acollierastro. Her channel and really good and she definitely deserves the shout out!!! Favorite question/Answer: Alderaan

[@cykkm]

VOTE VOTE VOTE Thanks for introducing me to @acollierastro! Dunno yet, but I'll certainly watch her channel for a while! Now, to the vote. Do you guys have a majoritarian(?) system where if my preferred bright-white toga _candidatus_ (lit. “whitened to bright white”) fails, the vote goes to the next selection? In case you do, I'm torn between these 1st and 2nd places: TATTOINE: the shaping of the Oort cloud(s) is a very interesting modelling and research area! And my next pref is DAGOBAH. The question whether there is at least one other intelligence in the Universe is of an uttermost importance. If only because it blows up the Copernican principle, reinforces the simulation hypo, and a lot of other things. It redefines not only our grok of the Cosmos, but also questions fundamentals of science. I give it a second place because the Oort cloud is a fact, and absence of other intelligences, existing, expired or future, is a widely open, very uncertain question. Thanks!

[@sarahgarrow303]

Hi Fraser - love your work! Especially love how you NEVER sound patronising or too highbrow for half-assed sky-watchers like me! I have a few questions: 1) This might be too dumb of a Q, but AFAIK, the moon's waxing and waning is caused by the Earth blocking the sun's light onto the moon. What i can't get my head around is: how can a spherical object blocked by another spherical object end up casting a STRAIGHT LINE shadow on a third spherical object?! 2) Do you think we'll see a supernova within the next 50 years, and is Betelgeuse the most likely candidate? 3) If we are made of starstuff, and the atoms in our left hand might be from a different star from those in our right, how does that fit in with us getting all of our DNA etc from our parents? Has our own personal carbon (inside our bodies!) been passed down all the way from pre-humans? / Sorry for the deluge of Qs, but space stuff just prompts endless questions for me! (Most of all, I can't believe that it's all REALLY REAL and just out there doing its thing ALL THE TIME, while we''re here just ordering a sandwich or whatever!

[@jonathanbyrdmusic]

Love that acollierastro video as well!

[@frasercain]

Yeah, she's a superstar.

[@WthyrBendragon]

A 2-part question... 1) How fast do gravitational waves relative to light? 2) Could a particularly near, particularly strong gravitational wave inducing event cause a cluster of earthquakes as it passes through us?

[@storyspren]

"The Zone of Don't Bother" is so much better as a name lol, "The Zone of Avoidance" sounds dangerous and spooky, whereas "The Zone of Don't Bother" has a more appropriate tone for the effect of just not being able to see anything

[@frasercain]

Exactly. I'll try to get that adopted by the IAU.

[@vadervanman]

How do stars that form a black hole also create a supernova? When the supernova happens, as it collapses, it bounces off the core to create the supernova. If the core turns into a neutron star, that gives the collapsing material something to bounce off. But if it turns into a black hole, what does the collapsing matter have to bounce off? Wouldn't the black hole just suck everything up?

[@joshuaentwistle960]

Question: What do we know about Omuamua now, in reflection?

[@junovzla]

I personally think that the reason the Oort Cloud is spherical rather than a disk has to do with the fact that it's really far away. Like, the reason everything else is a disk is that when the Sun was forming there was material falling onto it from all directions, but because nothing is perfect there was a direction where more material was coming in on average, so a lot of material ended up going by this bias sort of, through gravitational interactions and collisions, and it ended up averaging out into a disk. Now of course this bias must have been infinitesimal which is why all the matter orbiting the Sun combined is less than one percent of the total Solar System mass. But the thing is that when you're orbiting the sun you're going a lot faster if you're close than if you're far away, and my line of thinking about material entering orbit and averaging out works better if the interactions happen a lot more often, which is the case if you're orbiting fast, but if you're orbiting really slow there isn't nearly as much energy exchange so the material doesn't flatten out nearly as much, hence why the Oort Cloud is a sphere, because it's so honking big that it hasn't had time to flatten out yet. That's also why I think the size of planets peaks at Jupiter's orbit, because anything that was inside didn't have a lot of material to grow from because the orbital volume of the inner planets is smaller (and also the Sun's stellar wind stripped any major hydrogen coatings of the inner planets so that's a lot of mass that literally poofs away), and anything that was further away from Jupiter was orbiting quite slow so collisions weren't as frequent and planet growth is therefore slower, so as you get away from the Sun orbiting objects become smaller and greater in number (hence the Kuiper Belt)

[@levirivers2772]

Dagobah, I was a kid in school when the new science books came in with pictures of the Voyager missions. I remember trying to find as many pictures as I could find as many books were reprints of the best pictures but I remember clearly the first time I saw the "Tiger Stripes of Enceladus" & thought maybe 🤔.

[@CodAlmighty]

Hey Fraser, I've got a question.... Apart from life (at the moment) have we ever found anything in the universe that's unique? It seems to me, if something can happen once, it can happen twice, and if it happens twice then it probably happens countless times. Personally, I would expect that no phenomenon is truly unique.

[@oberonpanopticon]

Every phenomenon is unique if you’re specific enough

[@DrDeuteron]

Gravitational waves are not emitted whenever mass moves, it has to accelerate in a manner that is not spherically symmetric, so the GW signal from a supernova is sensitive to non-uniformities and turbulence in the collapse...and it's not a chirp, which is the signature of a rapidly decreasing orbit.

[@nathanielbyrne1132]

I vote for Hoth, a personal vote, cause Beatle juice is an absolutely mind-blowing star system

[@davidtucholski9583]

Whenever a question pops into my brain i write it down and procrastinate making a youtube account. 1. Regarding the CMB: The Planck map shows temperature variations. Black body radiation has intensity varying with temperature. I wonder if there are variations in CMB intensity that are not coming from temperature. For example lensing so that one pixel collects more photons than the other, yet with each pixel having a spectrum corresponding to the same temperature? 2. Regarding gravitational lenses: I often get the impression that it is implied that gravitational waves pass through matter without being damped. Yet I have a gut feeling (something something information theory) that interaction with an observatory would require some energy exchange with the gravitational waves, though. 3. Regarding black holes: If I'm not mistaken, for an outside observer, an object falling into a black hole appears to be moving slower and slower while being redshifted into oblivion, so that it looks like it never passes the event horizon. If said observer waits a long time (let's say that person has a PhD thesis to write and procrastinates by watching the black hole), the black hole eventually evaporates away. Does the object ever reach below the event horizon in the reference system of the observer? What does the math say about the position of the object in case the black hole grows? I'm confused, as all this would mean that there is no singularity. Where am wrong? 4. I remember you saying somewhere that there is some equivalence of ground-based to space-based telescopes regarding the resolution. Is there some rule of thump or is it just a wall of overwhelming detail (and depending on location, amount of adaptive optics, wavelength, dust,...)? 5. How does the gravitational potential landscape about 10ly or so around the solar system look like? How far do the spheres of influence of the stars reach, or do they dominate? Is there an underlying slope towards the center of the milky way? I hope I could express my thoughts clearly enough.

[@frasercain]

I like your instincts. Some of these are beyond my paygrade, though. 1. Yes, in theory some of the CMB we see will have been gravitationally lensed. astrobites.org/2012/02/18/gravitational-lensing-of-the-cmb/ 2. Waves do get damped as they pass through matter. That's how we detect them, but stealing a little of their energy. 3. As something falls into a black hole, the event horizon grows to envelop them, so they do get consumed and add to the mass. 4. There's no hard and fast rule. The high plateaus in Antarctica are probably the best place to put a telescope, no light pollution, cold stable atmosphere, but space is still better. 5. Gravity drops by the inverse square law. And it drops off fast. The gravity of the Milky Way is dominated by the dark matter halo, which is why stars orbit the center at the same velocity and not different rates like planets in the Solar System.

[@nanoflipps2871]

Expeditionary Force is a really funny, intense, way out there Sci fi book series. Recommending the audio books because it gives the edge you can't get reading it

[@Deuphus]

1). Mass is referenced by space and time and space is distorted by mass. Is time also distorted by mass? 2). Can both Voyager spacecrafts be used to run experiments measuring how the universe expands in 3D? 3). If physical attributes in the second dimension could be affected by attributes in the third dimension which would not be detectable in the second dimension, could attributes in the third dimension be affected by attributes in other dimensions which would not be detectable in the third dimension? Assuming more than three dimensions, could what is referred to as Dark Matter be other dimensions affecting phenomenon in the three dimensions we observe?

[@briancohen-doherty4392]

Dark Matter postulation: Given that "particles" of known matter are sharp peaks in fields , could it be that "dark" matter is more of a "dome" shape in the fields, too broad to currently be measured with current technology? We're looking for Everest, but it's actually Olympus Mons?

[@Dr.Wael.Alrifai]

Hi Fraser, how large/problematic are the dust particles in the nebulae. If I send my hypothetical spaceship through a nebula at high speed, will it be hammered because of the dust? Tatooine

[@highdromann]

Best question ever

[@gilde915]

Question...If we could understand Dark Matter and find a way how to influence it...could this be a way to manipulate gravity?

[@MaryAnnNytowl]

Just became Angela's newest subscriber, thanks to you - looks like my kinda channel, for sure!

[@nah656]

Are the new q&a shows still posted after the live version?

[@charleslivingston2256]

Kamino. Betelgeuse question: If it goes supernova when we are on the opposite side of the Sun, what does that do to or observing capabilities? I was mainly thinking in terms of telescopes, but also just the human experience. It would be a bummer to have such a great nearby supernova and have to actually have to look for it rather than it being so obvious.

[@frasercain]

The Mars rovers would see it, or Juno, but most of Earth's observatories wouldn't be able to see it.

[@tonywells6990]

L4 and L5 are more like hill tops than valleys, something there will drift away but eventually start orbiting around the point. L1, L2 and L3 are like saddles, something there will drift away or other things can fall towards it.

[@FloridaMan69.]

great video and i have a question so about field stars could they orbit galaxies? and if so does dat mean galaxies are bigger than what we currently think they are

[@prometeled]

hi, could it be that the invisible non matter=energy, is everywhere inside all physical object so as said can't be seen but thats what makes all systems looks flat ?

[@KOZMOuvBORG]

25:15Tte north magnetic pole was in Canadian territory for some time but is now moving north towards Russia 26:45 the Lagrange points of Jupiter are elongated zones straddling its orbit where the Trojan Asteroids dwell.

[@sjsomething4936]

(Dagobah) My vote is for Dagobah! It is an excellent question and one I also would find to be the most interesting one humanity could find the answer to.

[@ArodWinterbornSteed]

Q: Scientists talk about events that happened fractions of a second after the big bang, but at very high energies relatively says that time 'slows down'. Are there significant relativistic effects on the very early evolution of the universe? - If so, what would the difference be between our reference frame and a reference frame very close to the big bang? Would time be dilated for an observer in the instant after the big bang?

[@JamesCairney]

Coruscant Edit, coruscant sounds like a really ferocious way of instructing someone to sing the chorus. It's not why I chose that question, it was a good answer.

[@doncarlodivargas5497]

Do we have flat-oorters? I mean, in the USA there is anything, perhaps people insisting on the oort cloud are flat also?

[@ArodWinterbornSteed]

Q: What is the largest class of star for which there has not yet been enough time for them to complete their stellar evolution and 'die'? - Is the cutoff mass the same as the mass at which the stallar core becomes convectionally isolated from the outer layers? - Is there a significant jump in stellar lifespan at this mass-limit, and if so what is the scale of the jump in stellar lifespan? - Is there a 'gap' in stellar lifespan, i.e. should we expect no stars to have a lifespan, for example, in the range of 12 billion - 1000 billion years? -or are there other processes that might stop this from being the case?

[@frasercain]

A little less massive than the Sun. The Sun will live for a total of 10 billion years or so, and the Universe is 13.8 billion years. So sun like stars that were born 12 billion years ago could be dead by now.

[@michaelccopelandsr7120]

My idea so I get to name it! What I mean is, no one has claimed it so I'm officially calling, "dibs." Voyager 1 is now in Milky Way's interstellar time or "Mikey's Time." "V-ger's" message has sped up now that it's outside our suns time bubble or, "Terran Time." It will be faster still when "V-ger" sends a message from beyond the Milky Way's time bubble. (That name is still up for grabs.) Then there's Outside the Local Group time bubble, so on and so on until we get to the, "True Interstellar Time Standard." Now that "V-ger" is in interstellar space, it's also in the Milky Way's STANDARD, faster moving, interstellar time or "Mikey's Time." This can be proven by turning off everything except its clock and transmitter. Have "V-ger" read time for as long as possible. They WILL show the flow of time speeds up the further away you get from any celestial bodies. Until you reach the Milky Way's time standard or "Mikey's Time." •Our sun's time bubble: "Terran Time" we know and have measured. •Milky Way's time bubble or "Mikey's Time." The rate/flow of TIME outside any influence but within the Milky Way: We just got there and are still figuring. Wild guess I'd say time will increase in speed, now and until V-ger is outside the Ort cloud .007-.07% faster, maybe. Just for reference. •Local Group's time bubble or the rate/flow of time outside of any influence but within the Local Group: Name still open and unknown. Wild guess .08% to a couple seconds faster, maybe. Used just for reference. •Outside any influence in the, "True Interstellar Time Standard," or...;-P Name NOT up for grabs BUT just begging to be measured. The rate/flow of time is fastest here. (Time flows fastest here so it's best to have your motor boat.) ;-P A minute is a minute in all. It's the rate/flow I'm talking about. The Milky Way's Interstellar Time Standard will be known as, "Mikey's Time." Pass it on, please and thank you

[@parkey5]

Hey Fraser Please please please, I have a quick question. How far away can our sun be seen? For example we are seeing Betelguse change in brightness at approx 600 light years away. If there were a populated planet around there would they be able to look back at us and see our sun? Or would our sun be too dim? Love your shows, love all your work. Never stop 😊

[@frasercain]

You could see the Sun with your eyes out to a distance of about 30 light years.

[@parkey5]

Incredible, that's amazing. I thought it would be further, like 100 ly. So to starts within 30ly, our sun will make part of a constellation in their sky. That's cool to think about ✨

[@kadourimdou43]

28:56 Dagobah If you could see an astronomical object up close, what would it be and why?

[@oqsy]

12:00 “a ton” seems like a lowball estimate 😂

[@alexisdespland4939]

are there the equivalent of lagrange points beteen strs and or galaxies if either exist what are the called when where they discovered.

[@smithtorreysmith]

Naboo How do we go deeper here? The oh Bang as the mirror image other side of a Black Hole seems to address some of the intuitive questions we ask.

[@dimitriskai261]

@frasercain about Bespin: I'm trying to comprehend the chronology of the supernova event, as you described it. The outer layers collapse on the iron core and that shock produces the gravity waves we receive. These propagate at lightspeed. Then, energy is produced and because neutrinos are not blocked by the outer layers this is why we detect them after the gravity waves. And lastly, nuclei repulsive force overcomes gravity, and the rest of the energy produced tears through the collapsed outer layers. This is the supernova explosion and we observe it as visible radiation, and not only. Now considering that from what I'm reading neutrinos travel a bit slower than light my main question is, how much times elapses between gravity waves, the neutrinos' burst and the actual explosion? Is there enough time for us to run to our telescopes and watch the supernova? I 'm guessing all these observations are happening concurrently but I find their timetable very interesting. Thank you for your very informative videos.

[@sanlinhtet1170]

Hi Fraser, can James Webb see through the stars behind the zone of avoidance?

[@frasercain]

Yes, it's an infrared telescope, so it's great at seeing through the gas and dust at the center of the Milky Way.

[@211212112]

I thought the universe is expanding due to virtual particles popping into existence then out of existence all over which pushes everything apart. The greater the distance between objects the greater the number of particles doing the in/out dance and the faster the objects are pushed apart.

[@seasonedbeefs]

Nice concept

[@ourcollectivewisdom8769]

Here’s a question… is there any evidence that the universe exists within an external medium of some sort? If so, what is it, and also what are the implications either way?

[@ZeroIQ2]

Another great video thank you Fraser! I just imagine that somewhere there is an alien Fraser that already knows there is life on Earth and is trying to find a way of letting you know, but is annoyed at the pesky slowness of the light speed problem lol.

[@frasercain]

I'm waiting for his signal

[@zrebbesh]

What I hate about that "disc inside a sphere" image is that nobody ever points out that the distance scale is sun-centered and logarithmic. That thin shell marked "oort cloud" is hundreds of times wider than everything inside it.

[@linkleisure]

If we can tell Betelgeuse is about to go supernova . I wonder if any woodbe type one or two civilizations closer to Betelgeuse might be getting nervous these days. if so would they be making moves to protect themselves from the explosion ? do you think we might be able to see any signs of this from here ? like scaring fish out of the weeds

[@davidguillen6611]

It likely already went supernova a couple of centeries ago.

[@filonin2]

@@davidguillen6611 That's not really relevant if we're trying to observe civilizations who would also be far away and in the past.

[@PitchWheel]

Does it make sense to say that, after all, our solar system is the accretion disk of the sun and our galaxy is the accretion disk of Sagittarius A* ?

[@berlinontwowheelsberlinauf1958]

Question: While travelling through space at relativistic speeds - would gravitational waves have any impact on the travelling ship and or the travellers?

[@frasercain]

If they were strong enough, but you'd have to be insanely close to colliding black holes, and you'd have other issues to contend with at that point.

[@InternationalKarl]

Tatooine very interesting never thought of it

[@lookspacethings]

Hi Fraser, I have a question. Why aren't we looking for Nitrogen in the atmosphere of exoplanet to decide if they are similar to Earth? Most of Earth atmosphere is Nitrogen. Why I only hear that we are looking for water and oxygen?

[@AlexxBabee073]

Kamino, love Angela’s videos!

[@frasercain]

Agreed!

[@CosmicRadioOne]

Glad this channel cleared up difference between a disc or sphere by using giant arrows. Would be slightly less condescending next time if they just put a photo of a cat, with a big arrow pointing at it, and the word "C A T".

[@frasercain]

We're always trying to help. I'll suggest that "CAT" idea to the team for the next thumbnail.

[@CosmicRadioOne]

​@@frasercain Glad to hear that you will consider the cat thumbnail suggestion! I'd actually prefer it to the current one! Plus remember all those O'Reilly programming books with animals on the cover... The animals didn't have anything to do with the programming language--well except for the snake on the cover of the Python books!--but people loved it. So who knows...

[@jasonsmith373]

I must be doing something right. I started watching Dr. Collier & Fraser independently, and damned if Fraser didn't site one of her videos that I recently watched. 🙂

[@frasercain]

Clearly the algorithm recommended the same videos to us. 😀

[@miguelroucado6280]

I hope I can present a question here. I would like to know why Cientis says the universe is flat instead of a sphere shape. How can they justify that matter starts on a single point, that has forces pulling towards everywhere and in the end, the matter "chooses" to move only on a single plane. Could this statement be influenced by our range limitations on the observable universe? hope

[@mshepard2264]

❓I heard that tons of saturns ring particles enter saturn atmosphere every second. Would there be a detectable radio signal associated with this accretion process?

[@scottmedchill4210]

Question: Could we find out if metallic hydrogen is metastable by looking for asteroids that contain metallic hydrogen in their composition?