Largest Stars, Dark Matter In The Solar System, Science Being Slow | Q&A 252
ฝัง
- เผยแพร่เมื่อ 31 พ.ค. 2024
- How heavy are the biggest stars in the Universe and how do they compare to the Sun? Why would aliens be grabby? Is there more space for science communicators? What's the minimum size for an object to have an atmosphere? Answering all these questions and more in this week's Q&A show.
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00:00 Start
00:28 [Andoria] How big are the biggest stars?
05:35 [Vulcan] How fast should colonising the Universe happen?
10:27 [Risa] Why would aliens be grabby?
13:51 [Aeturen] The difference between humans and aliens
16:14 [Vendikar] A star approaching us from the Large Magellanic cloud?
20:27 [Remus] Is the scientific discovery process slow?
24:06 [Janus] How do we know what happened before recombination?
28:19 [Cait] Is there more room for science communicators?
33:13 [Betazed] What are my interest outside of space and science?
36:17 [Cheleb] How fast do different galaxies move away from us?
37:38 [Nimbus] How much dark matter is there in our solar system?
38:31 [Belos] How big does an object need to be to hold an atmosphere?
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You are free to use my work for any purpose you like, just mention me as the source and link back to this video. - วิทยาศาสตร์และเทคโนโลยี
Eager Space is one of my favorite channels! It has the perfect mix of seriousness and cheekiness. The biting sarcastic humor often comes with zero warning.
We have been getting non-stop content for some time now. I can't put into words how happy this makes me.
Earth is flat and non rotating with a local sun! Na$a.gov Wake up folks! Jesus saves sinners!
love that he keeps in the blooper at 16:58 Sorry if you were having a bad day sending good vibes ~~~
haha yes, but the audio level reduced after that a bit
Earth is flat and non rotating with a local sun! Na$a .gov. Wake up folks! Jesus saves sinners!
Thanx for picking my question, Fraser! I now have to brag to my friends and family! 😊 so… Andoria!
There may be a string of 7 dots under the Moon during the eclipse...That is our binary solar system minus its brown dwarf star much more distance away..
Na$a. Gov--- We live on a flat non rotating earth with a local sun! Deep space is fake! Wake up folks! Jesus saves sinners!
The forest floor is as violent and as competitive as a coral reef. The plants are not sharing resources, but grabbing what they can and smothering every other plant in a frenzy of competition for energy.
Fraser, that little rant at the beginning made me chuckle - I was thinking "Woe, who rattled Mr Cool's cage" 🤣
I was having a very similar thought…
Like, “Who the h311 has been putting so much pressure on Fraser about accuracy on ever changing information?”
Routinely engaging with comments across a channel like this could probably test the patience of even historically stoic Vulcans.
Na$a.gov. - we live on a flat non rotating earth with a local sun! Deep space is fake. Wake up folks! Jesus saves sinners!
Na$a.gov. We live on a flat non rotating earth with a local sun! Deep space is fake! Wake up folks! Jesus saves sinners!
Mumbling: "Stupid microphone!" (16.55). You made me chuckle with that one. 🙂
Vendikar is kind of objectively the coolest and most important story this week, galaxies exchanging stars and all. I also appreciated your thorough answers to the questions about the pace of scientific discovery, the state of science reporting, and your personal interests/backstory.
You definitely found your calling Fraser, and for myself as a young adult reading Universe Today many years ago it was obvious you like what you do, and continue to do today. Thank you!
Mars Guy is an awesome small channel for weekly Martian geology updates found by the rovers, with info and sense of humor, but the vids are so short!
Love the channel, I watch quite frequently. I also don't understand grabby aliens and the idea of a civilisation expanding. It's obviously technically possible to send out these probes, and on the timescale of a million years to colonise a galaxy as you mentioned, it could be a 'civilisation' coming for us, but the time required to transit between galaxies starts to change things for me. I saw another episode theorising this expansion would be at roughly 25% the speed of light, so even to andromeda galaxy, it's upwards of 10 million years to make the journey, and like you said, hundreds of millions to billions for many other galaxies, which mean the 'civilisation' that launched these probes is certainly extinct or at the very least has evolved into something completely different, so is the ultimate threat of grabby aliens not a 'civilisation' coming for everyone else, but a fleet of probes that barely remember their planet of origin expanding into the cosmos like the replicators from Stargate? In the other video, they theorised it could also be generation ships making the journey, but again, at 10 million or 100 million years to reach the next galaxy, the people on that ship wouldn't even remotely resemble the people that originally left and certainly wouldn't remember anything about the original mission or their home world.
this answering questions was one of my favorite of your videos. clearly you do a lot of in depth research. Thanks
Vulcan - I loved your explanation of how there would be an initial wave of probes, with backfilling behind them. That painted a much clearer picture of how an expansionist space-faring civilization would operate!
Absolutely right! It feels so sad to know that you will probably not live to see some of the discoveries that are already imaginable. But on the other hand it's absolutely MINDBLOWING what discoveries already have been made within my lifetime so far... When I think back to astronomy books from the 80s or 90s... Just wow!
Love your q&a videos love falling asleep to them keep them coming!
I'd definitely watch a channel you did 'on earth' developing a forest area you own before you're too old, I'm 52 and love this channel but am excited to see if you branch out, you have a great presence.
Aeturen thank you for clarifying this for people!
Another great video. Great to see you on the interwebs.
Eager Space is amazing! I especially like "You Suck at Space". It quite literally changed my outlook on life.
Fraser, I like your description of restoring your native habitat on Vancouver Island. I'm engaged in a similar project in New Zealand on a 'cut over' pine plantation. The non-native radiata pine act as a wonderful nursery for the re-emerging native ecosystem and I selectively prune out the pine as the native forest matures. It's an incredibly satisfying endeavour.
Learning about the largest stars, dark matter, and the mysteries of our solar system in one video?Mind-blowing.
It was very interesting as always, thank you very much. And the best success with your forest restoration project!
Oh no way!!!! I just listened as I worked and picked up you live on the island! Been listening for ages and didnt even realise that! Im from Squamish :) we should hike up to the top of Garibaldi and film a show 👀
He actually used to record space bites from the forest of Vancouver island
@@redcoat4348 think ive seen one i just never paid attention to the location stuff lol
As always you are interesting and thought provoking.
Thanks for including my question Fraser… Great answer/explanation 👍 #Vulcan for the win! 😊
I love your optimism about how fast science discovery is.
1:38 the best tangent I have listened to in a while.
Listen to the previous 30 seconds
YES Please start a series on our amazing Vancouver Island. I’d be so honored to help out, speaking as a fellow islander (Campbell River area). 😃😃😃🇨🇦.
PS. Fav story this week Belos.
Remus. I recommended eager space so I’m glad to see him recommended in this video now, he really needs the attention and I also appreciate how he covers the business aspect of space startups. I would also recommend the AnthroFuturism channel, which also has under 10k subscribers.
Fraser, read House of the Suns. It is a great sci-fi book dealing with near light speed travel.
@frasier a tip for your microphone - if you put its base in a new tissue box it dampens desk sounds. also probably will help with frame vibration transfer.
Fraser your videos are so appreciated.
ok you remember some long term missions, i remember voyager launches... talk about long term space projects. but still i have this impatience of discovery not happening fast enough ,but also overwhelmed with present flood of new discoveries. what a dichotomy !
thanks for what you do!
Great to hear about other things you are interested in and your story of how your space career evolved :)
On the subject of "Grabby Aliens" may I mention Isaac Arthur and his "End of Civilization" videos?
THATS why we might want to be somewhat "Grabby". Thanks, Frasier! Love your channel!
Isaac Arthur is Sci fi
Hey Fraser, great show as usual. Thanks for all you do. I have a question for the Q&A. Now that Bennu is so well characterized, has anyone done a study on exactly what would happen if it impacted Earth? Let’s assume for the sake of the question both an impact angle of perpendicularity and, for simplicity’s sake, 45 degrees inclination. Thanks!
Fraser - a video about Vancouver Island and how it needs to be returned to the way we found it would be epic - I love Vancouver Island, although not been back for over 25 years sadly, if I was going to live anywhere else outside the UK, Vancouver Island would likely top my list - although the weather may be a deciding factor!
Andoria - because your disclaimers made me lol. 🤣
Vendikar.. mostly because your answer clarifies a persistent thought of mine; we could get a higher relative velocity traveling to an object that is moving toward us..
I didn't really have a favorite question but my favorite answers were both to [Cait] which prefaced into [Betazed] that I found positive, inspiring, and hopeful.
Oh man that Osiris Rex shot brings me back. Had the incredible chance to be there in person as well. What an incredible experience
To hear that you are into natural restoration and rewilding is so fantastic. I would love for you to find a way to incorporate more of this and direct more people toward things like @MossyEarth or other channels you might recommend.
Love the channel! I have always liked UT but I don't read it that often. I think you are a great writer but you are equally good at TH-cam, I'm a big fan, just tuned in recently. I hope you keep doing YT content. This is one of my favorite channels now. I have a question; I recently read "Delta-V" and "Critical Mass" and now I'm reading "The High Frontier" and it's like my new religion; Do you see the "O'Neill roadmap as realistic?
I haven't seen this one answered anywhere yet but I've been trying to figure it out unsuccessfully. So I'm reaching out to the big guns. I just found your channel and you go deeper than a lot of other science communicators, which I love. So, how do we account for gravitational lensing of the CMB? Do we really have an accurate model of where ALL the matter (both light and dark flavors) in the entire observable universe is, enough that we can reliably un-lense the CMB? Are we just guessing? Or completely disregarding the effects? It seems to me we would need to account for this.
Hey Fraser! Here a question for you.
What kind of life from Earth can survive and thrive in other parts of our solar system? And which parts of the solar system?
Vendikar
How hard do you think it was for Fraser NOT to mention Gia data lol
Eager Space is amazing! I know that channel, how did I not suggest it?! I thought it has much more subs 😅
A) If all the matter of the universe started from a single point, a super super massive black hole, how was it able to expand?
B) Is is possible that space and matter were not created at the same instant in time? That is, if, in the beginning, energy was converted space at a similar ratio that matter is converted to energy then, could the left over energy from the creation of space compress or implode to create matter.
Cheers.
The explanation for the Grabby aliens, for me, is the exact reason that we have the Fermi paradox exist and that we never had real contact!! We are way to grabby as a species to be aloud to go further than our solar system!!
Fraser .. But in 1399 AD - you said the largest star was in the Sol System
Hi Frasier, two questions today.
It seems reasonable to me to assume that when stars send out solar wind, it's composed of very light particles, mostly. If those particles are less dense than the average density of the star, wouldn't that imply that the star's density would then rise? Could you theoretically have a star turn into a blank hole with no supernova if it was dense enough and lost just enough solar wind?
And as for the grabby aliens idea, your comment about the Culture gave me a new thought on that topic. If enough civilizations were non-grabby and stayed within a small area of the universe, but defensive against grabby aliens passing through, wouldn't that provide an explanation for the paradox? Couldn't there be enough defensive inward focused civilizations acting like an immune system to explain a lack of both grabby aliens and signs of the defensive aliens?
Hi Fraser! Love your channel. Thank you for all you do. Can you please explain the difference between a nova and a supernova? I heard there is potentially an upcoming nova event and want to know more!
Yes, an interesting Nova event, this is a recurring nova event (forget its name) of a red giant and a white dwarf binary star system, happens every 80 years & is due basically anytime from now to Sept I believe, with guesses around May-June. Think I saw it on Anton Petrov channel. It’s about 3000 light years away, meaning while we are awaiting it to show itself soon, in reality it has already happened, possibly 37 times already, if there hasn’t been a supernova event during any of the already happened recurring event possibilities of it’s red giant neighbour which ponders further the possibility of the white dwarf being one of those ejected stars scenarios. Like to hear Frasers take on this event also.
Remus for daydreaming. I was 8 when Appolo 11 tounched down at Tranquillity Base. I had an astronaut GI Joe with the Gemini capsule. Over the years I have followed many programs and space firsts. Was all in with Osiris-Rex from beginning to now. Voyager II & I when I was in high school. Still love an update on VII &VI. I do get a little bummed when I hear about potential missions in 2050+; I'll never make it to see it.
Frasier, your answer about the volume and the masses of different stars was a star on it's on. Magic Frasier YOU are a star
If time and gravity are linked does that mean that just after the big bang time moved liked honey and as the universe expands and gets less dense then time is always speeding up?
Not really. Time and space both only make sense when compared. Time is always the same for any specific reference frame. If you get on a near light speed spaceship, time seems normal to you. You just look slow to others and they look slow to you.
@@adamredwine774 If You are driving a car at 40 km/hr and me at 70 km/hr,
even you will look slow to me.
Gravity does effect time. We know time moves faster on top of mountains than at sea level. So that might mean time is moving fast in between galaxies which might mean our measurements are wrong. Which might mean we only perceive the universe is expanding when it is not.
@@RectalRooter It is true that gravity affects time but your statement about universe expansion is incorrect.
@@adamredwine774 Sorry. I wasn't trying to make a statement. I figured the word "" Might "" showed that. I will try to be more clear.
Belos. Fascinating. Who knew?
I would prefer explanation with some *quantitative* analysis.
For example:
The state of outer layer of the star (which determines the color/temperature and star's size) does not depend on internal structure of the star below it (whether the star has a very dense core, or not, it "does not care").
Only a few variables are important:
- the total mass of all star material below the layer in question (but not its detailed stratification)
- the power output coming from below
- the composition of the layer (H/He/"metals", but for most stars, it's 75% H, 25% He, only metallicity varies a lot)
- how fast the star rotates
So. If the star is heavy, the gravity is stronger, the outer layer is held to the star more strongly, and the star is smaller and bluer (for the same power output).
If the star generates more power, the outer layer becomes more extended and redder (compared to less energetic star).
Higher power generation happens in heavier stars, but NOT ONLY in them! Stars later in their lives have their cores shrink due to fusion fuel getting depleted - and dense cores need more power output to resist further collapse - IOW: a lighter star may nevertheless generate more power than a heavier one, if its *core* is more dense)
Thus, the largest stars are not the heaviest ones, rather, they are the old stars with high power output but relatively small mass. In fact, such stars end their evolution by contracting their cores, increasing power output, and expanding so much that at some point what used to be their outer layers becomes a planetary nebula - it suddenly gets transparent and you can see the former insides of the star: a tiny, hot (above 100 thousand kelvins) core blasting the outflowing gas with copious UV radiation.
If the star has low metallicity, its matter is generally more transparent to light (longer "mean free path" for photons, because H and He have relatively few emission lines, and fully ionized H and He have even fewer ways to scatter photons) - IOW: energy exerts less pressure on the plasma as it escapes from the core, through all the layers, into space. This means than low-metallicity stars are smaller, all other things being equal.
There are various complications, such as "helium flash" and other transients which may, foe example, make the star shed the outer layer (due to temporary large power increase), but retain the rest of the star, and if by that time only outer star had any hydrogen left, the star may end up having only helium outer layer. There are even stars with *carbon/nitrogen/oxygen* outer layers (and they STILL have fusion going on inside, not dead yet)! These are Wolf-Rayet stars. Some are so "sooty" in their outer layer and stellar wind, they shine more in the IR than in visible light!
There are also binary star mergers, and many scenarios of mass exchange in binary systems, either adding fresh hydrogen onto old stars, or stripping a lighter star to lower mass, sometimes to below minimum stellar mass, ending up, for example, with bizarre "helium planets" which are really old star cores stripped below 0.08 solar mass.
Wicked Awesome show A.
If BAT99-98 is fusing hydrogen like R136a1 then it is a main sequence star and by definition a *dwarf.*
@frasercain
With Fraser's seemingly obsession with GRABBY Cain Aliens -- Is he projecting ?
Should I worry aboot standing next to him in the grocery store line ?
hahaha
Fraser, can you let us know what your thoughts are about David Grusch?
I don't have any thoughts. I just need to see evidence.
An arguement for the 'transenderizers' is that the time and energy needed to move physical matter over cosmic distances just doesn't make any sense?
Hey Fraser,
I've heard it said that the Schwarzschild Radius of the Observable Universe is the same size as the radius of the Universe as a whole. This seems to imply that the whole Universe is inside its own giant black hole.
So instead of resorting to Dark Energy, might we explain the expansion of the Universe as just new matter falling into this black hole, causing the event horizon to grow, and bending Spacetime even more with its mass?
-az
So much energy and zeal.
Dear Fraser, i am a big fan and i got a question for you: why is the higgs particle not the solution to unify qm and gravity? it seems so related, isn't mass just like that already quantised?
Hi Fraser what's up with T Coronae Borealis? & what's the whole deal with this recurring nova?
As a follow-up to the Vendikar question, how long would it take us to figure out that our sun and solar system has been ejected from the Milky Way? Would the Milky Way just get smaller and smaller in the sky over decades before we realized any difference?
If we were able to come to a complete stop, negating all movement relative to the big bang, how much faster would time be flowing?
Fraser the passionnate man!! more and mre I klearn anut that man and the more I appreciated your work.
That is literally the first time I have ever heard anyone mention, Terraforming the Moon. Go for it. You could even come back to Earth for the weekends.
NB. No matter who sets up a moon terraforming project, even if it's us, they should be labelled 'Moon men' and declared as hostile.
Hi from Vancouver Island!!
"Why do you assume the aliens want to colonize the entire universe?"
Copernican principal applied to our own species, there's already several thousand people on Earth that want to do this who will leave at their earliest opportunity, they probably have their own contingent of reflexively hyper-expansionist eccentrics as well.
Cait -
Given that the LMC seems to be much more "primordial" with its gas environment than most galaxies, and that only very recently has interaction with the Milky Way started a wave of star formation, to what extent might currently-being-created stars in the LMC resemble Population III stars? To what extent do the LMC and similar isolated galaxies today strongly resemble very early galaxies?
(at the end of Vulcan) where did you get this picture of an UAP? Because I know it vey well; it is a model of the space ship Orion, from the science fiction show Raumpatrouille, made by the ARD, Gemany, in conjunction with the French TV in 1966. In contrast to the Star Trek series it was still made in black and white, and has its follwers as well.
I heard somewhere in order for a graviton to exist, you need negative mass. Since dark energy counteracts gravity, can it possibly be a candidate for the elusive graviton particle ?
So with stars returning from some black holes is there a way to detect how old they are or where they come from?
"Slow down science so i can digest it"
Just
So much no literally all the no
EXCELLENT content though big respect for keeping an eye on arxiv💪
If all universes are moving away from us, then do we understand the center of the universe?
@hi fraser, shouldn't the neutron star be the most massive star (in terms of solar mass) in the universe. My understanding was that neutron stars are the most dense object in the universe, need your thoughts.
Question
Are we able to post Cosmoquest Forum links in the comments ?
I miss the original green screen, those trees almost looked real ;-)
Hi Fraser! Could lightning storms on Jupiter or other gas giants be frequent/constant and powerful enough to act as a artificial sun deep beneath the atmosphere?
Belos and thank you.
My personal hunch about the Fermi Paradox has long been that Von Neumann probes turn out not to be feasible even with theoretical future super advanced technology.
Interstellar space travel is just too hostile for sensitive machines that are not very heavily shielded and built with a lot of redundancy. Spacecraft that ARE robust enough would face increasing challenges in manufacturing copies of themselves, and would be larger and more difficult to accelerate to relativistic speeds and also decelerate to come to a stop in their target system.
If these factors combine such that the resources required to project your probe cloud to a larger radius increases exponentially, then that effect could overpower the compounding effects of self-replication.
Fraser, Question, do you know why stars disappear? Many stars, reported, simply disappear. I've thought black-hole, but no since the light would bend. I thought dust, but that would defuse the light. I have no explanation
Rewilding 👍 35:44
Fraser, if you could have one question answered about anything, what would you want to know?
5:38 The Fermi Paradox only exists for those who haven't already seen for themselves, and is basically... IRRELEVANT.
Slow science? It depends on your point of view. My grandparents lived from the horse and buggy days until the space age, born before the first flight of the Wright brothers and the discoveries of X-rays, radioactivity, and relativity, and yet saw men on the Moon. I was born just before WWII, and was impressed that our soldiers had semiautomatic rifles. Aircraft, ships, and submarines improved with every newsreel at the movies and radio news broadcast. After the war, planes, trains, and automobiles improved by logarithmic (not quantum) leaps. Five years after the war (the big one) commercial TV hit, and TV antennas sprang up like weeds. Bouncing radar off the Moon was headline news. Captured V2 rockets showed the curvature of the Earth. Fission nuclear devices blew holes all over the desert and filled the air with strontium-90. Hydrogen bombs vaporized islands, and we loved it. Our first attempt to put a satellite in orbit failed because Eisenhower wanted the rocket to be civilian instead of a proven military one, and the Soviets beat us to it. They beat us at every step until Armstrong's first step on the Moon.
Around 1950 when I was in grade school, it was thought that mountains were caused by the shrinking of the Earth; that the Moon was flung off of a rapidly spinning Earth, leaving the Pacific Ocean basin; that the craters of the Moon were all volcanic; that the continents had stayed put for the entire age of the Earth, and continental drift (plate tectonics) was the fevered dream of a mad meteorologist; that the dinosaurs had gotten too fat and lazy and had turned into oil; the eternal steady-state universe was a respectable position to maintain.
After that, I admit that the rate of advance has not been as frenetic, with the Space Shuttle (the most advanced delivery truck ever made), all the space probes, the first plans made available to build your own computer 50 years ago, the first commercial PC's a few years later, cell phones about the same time, relatively cheap flat screen TVs, GPS, and smartphones with everything but a toilet app.
From my point of view, there has been more scientific progress in my lifetime than from then back to the first human who wondered about those points of light in the night sky.
Risa: I guess we humans are like that. There are probably some people whose ancestors all lived in East Africa for 200,000 years, but there was a group who wanted to live over the horizon… and here we are.
"Why would aliens want to consume the whole universe?"
Have you SEEN Exxon?
hahahaha Right ! Grabby could be the universal normal habit. Not just normal human habit.
Great!
As a black hole evaporates via Hawking radiation, what do we expect to occur? Does its mass reduce slowly down to zero? Does its radius get shorter and shorter in proportion to its mass? What I'm wondering is there any mechanism by which the density may cross that threshold and it may un-become a black hole if it's only evaporating and not consuming any new material.
Question - Of the total amount of water in the solar system, what % is here on Earth?
If all the known black holes in the universe merged, how large would the event horizon be?
Question - Why would any species want to convert or consume every resource in the Universe?
Fraser - They won't, but some of them will! And mention Borg from Star Trek that can travel 5 000 000 000 faster than the speed of light.
I have a better analogy, imagine you plant an apple tree to get some apples, but this tree need to grow 10 000 years, and even if it will grow, your future generations need another 10 000 years to even get information about successful apple growing, why the hell you will plant that tree?
Remus-I hear you
Vote: BELOS Also, is there any way to create an earth like atmosphere on the moon?
Fraser, now that you've made that preamble (~ 1:35 ish) I'm gonna HAVE to wait till they list a NEW largest star and then come back here to say "Umm, actually..."
I'll have to come back here and do that each time a new, NEW largest star makes the list, but that might make for a fun game to while away the decades...
I already put in the disclaimer. Your updates will have no effect on me.
@@frasercainI totally understood ur disclaimer as I see new videos every day regarding new finds with the JWST often accommodated with click bait titles, or maybe the astrophysics community are just a very stressy lot when their beliefs & models are thrown into disarray, they don’t seem to think the universe should be able to just keep doing what it likes against their rules & models, ah well, what can you do when a universe just wont behave?
How large can moons get? Can they be significantly larger than what we've discovered so far? Could a moon be the size of say, a gas or ice giant? Or is there a cutoff that we are not aware of?