I don't know why but I always drop the "millions" when I'm mentioning large light year distances. For the expanding question, it should be "tens of millions of light years", not "tens of light years". Unless Chad is actually cutting out the millions part to gaslight me so I think I'm going crazy. I'm not crazy, you're crazy!
@Fraser Cain It's perhaps much easier than you might think to escape a high-gravity planet: For example, I developed a fairly inexpensive launch platform for orbital satellites, using weather balloons to hoist said platform approximately 18 miles above the Earth's surface before launch occurs. This kind of system may well be scalable on a planet with much greater gravity.
So if you're curious why someone might ask you a question about the great attractor it's because news as far as astronomy goes is not very good. A lot of the time if you open an article that is ostensibly about some very specific thing it'll start out with a giant generalization about the entire field just to eat up space. It's really awful honestly. Not to say that all science communicators are like that, you're not for instance. But the majority of people when they look up some concept what they get is just some really Bare Bones entry level astronomy
@@johnstrawb3521 Fraser has covered the problem before. Here is a quick summary. To achieve orbit, the vast majority of the energy goes into sideways motion, not vertical motion. A balloon or even an airplane does very little to help this. The biggest savings is avoiding the higher drag of the lower atmosphere. While significant, it is small compared to the total energy required. If you want to achieve escape velocity straight up, the problem is the max height of a balloon. A balloon can only increase the distance from the center of a planet by less than 1%. This has a negligible impact on the energy required. Note that you are far from the first to come up with this idea. That is why the calculations have already been done. You are in good company, but sorry it doesn't work.
Fraser, a great show as usual. That said, you might buff on your understanding of grinding a telescope mirror at home. It is nothing like you described. You take two flat circular pieces of Pyrex (not optical glass) and grind them back and forth. Over time, you will find the two flats come together as a PERFECT sphere (bottom glass convex and the top concave(your mirror)). With a very simple device to magnify the mirror surface a 100,000 times, you hand polish a parabolic curve. You can this curve to within 1/4 a wavelength of light. The old guys writing in Amateur Scientist in the 30’s used used flat windshield glass to grind together! When finished, send it off to get silvered. I made one 50 years ago.
Great response to [Bespin] (the big bang question)! Thank you for modelling journalistic integrity and appropriate levels of respect for expertise instead of armchair speculating. I wish there were more of that on the web these days. It's also important to remember that people can be experts in one thing and know very little about everything else. Subject matter experts could do better in this area too. Unfortunately I can think of some high profile people with PhD level expertise making ignorant public pronouncements about things in unrelated fields, or even closely related fields that they still weren't experts in. That only degrades public trust in expertise in general and promotes crackpottery/conspiracy theories. Experts: it's okay to say you don't know something! Okay, I'll get off my soapbox now.
1st time watching your video, but I like how it's not annoying dramatic. I see a lot of these videos mentioning TERRIFYING this or that. Space isn't terrifying its Beautiful! Like the creation of a Star, it's an amazing and wonderful process. Other part I enjoyed about your video is accuracies. A lot of TH-camrs hear of an idea one scientist has and they try and make it way more crazier and scary sounding, so they get views. Our Universe is amazing already you don't need to up "Amazing" Thanks again!
The launch was awesome! I am always amazed at the precision of all space missions, especially the longer range ones or ones with multiple flybies. Would you talk a bit about how they make that happen, how they have taken something so complex and made it into something seemingly simple with such a high success rate and precision?
'i am not educated enough to have an opinion' - such a wonderful insight, such a shame people generally don't possess the humility or the self-awareness to reach the same conclusion. nowhere is this shortcoming more obvious than on social media. and so, my vote goes to Bespin. by a light year.
We need to learn if its an isotropic universe or not. We thought we knew but now the measurements makes this the #1 priority. We can't even ponder things without this being known .
The whole idea of collision-less matter is interesting. Now harvesting collision-less mass? That's a bit further ahead. Maybe we can understand how it orbits and interacts with black holes first? What dimension to you need to be in to see their interactions sans spacetime geodesics? Is there a higher dimensional model that is even close? I know string theory can tease out DM but that's the problem with it. It can tease out a lot of things which can't be not just directly measured but can't be inference measured either with the physical tools we have so far.
Bro, your answer on the Big Bang question was really good. Wish all journalists had that kind of objective view of their job instead of trying to craft things. Just the facts ma'am. O7
11:00 From the perspective of the photon, from the moment it was created, it hit your retina and was processed by your brain. Since photons move at the speed of light, time is stationary. Even though it took as many as millions of years to make it out of the sun, it simply was; then it wasn't.
Observations indicate that the observable universe is expanding at an accelerating rate, what is the current thinking of the universe in its entirety. Assuming that the universe in its entirety is infinite in size, it matters not if it is expanding , contracting or remaining static, it will always be infinite in size and must always have been.
Bespin for sure Such an interesting topic How can we know anything? It's difficult to find a perfect answer. 99% of all experts can be wrong, but they usually aren't.
Strictly it is or may not the same photon which is given of by the gamma radiation. Once it is absorbed by an atom it becomes part of that atom. That atom may not give of a photon but if it does it will not be the same photon. 🙂 You said this just as I was writing it
How many years would humanity need to wait until we are on the correct side of the galaxy to start observing the Great Attractor in greater detail, perhaps in visible light?
Here’s a question I hope you will answer Fraser. My 4 year old asked me why the moon is out some nights and not others. And sometime’s it’s out in the day. I’m not sure how to answer her… I know the earth spins and sometimes the moon is on the other side, but what is the pattern?
The Moon needs 28 days to complete an orbit around Earth. Also, is tidal locked to her, so The Moon always shows the same face to us. See, for example: th-cam.com/video/arvOgLpfucE/w-d-xo.html
7:30 ......you can never ever use up the force of gravity, we just haven't figured out how to harness it correctly as strange as that might sound. And if you do I hope you find the right path out to the light!
I seen somewhere here on youtube that if there was an atmosphere between the earth and the sun, the sound levels at this distance (93000000 Miles) would be about 290 decibels . An incredible amount of energy. Could dark energy be the un-manifested sound of all the trillions of stars and debris throughout the universe ? Imagine the sound of an accretion disk around a black hole! Where does all that energy go if it can not manifest as sound waves?
question: if you took a yardstick and put the quantum realm at the 0 inch point and the universal realm at the 36 inch point, where would humans be on this scale of magnitudes? physically speaking? are we closer to the tiny world, or the massive world, or somewhere in between?
I reckon for the past 300 years people have suspected that space itself is not flat. You can look at the Virgo cluster with a fairly small 16" telescope and clearly see that space is distorted. I think its called weak lensing basically everything in the eyepiece is curved.
What if when you try to pull the quarks apart the glueball size is increased which pulls more gluons into spacetime to maintain the gluon concentration which increases the pull. I believe a significant amount of dark matter is gluons which are part of what I call the QL soup. Do we have the technology to tug on a quark and see if the weight of nucleus increases? The Quark Lepton soup is outside of spacetime which is just a bubble in the soup.
I appreciate yr answer to Bespin. I will say the avg time to.complete just the PhD is about 10 yrs not including the previous degrees required. It's likely decreased recently for lots of reasons but 3 to 5 yrs would be very fast. Chronicle of higher ed has data available on this subject.
Hi Fraser. Love your work. Do we know how much frame dragging is occurring around galaxies and to what extent it affects the speed at which galaxy arms are rotating? Or in other words, is it possible that the rotation speed of galaxy arms is affected by frame dragging as well as dark matter?
Mater can go to Energy and Energy can come from matter, but consider one more level that Energy can go to time space what we define as nothing, but it’s a real tangible thing. From a Plankxel, point of view everything is entangled to some degree. As matter or photons smear across the Plankxel grid like a photograph these elements smear into a sort of wave, but the smear can go into the past as well. This allows for the paradox of creation, but it also allows for the expansion of the universe. So, consider an anti time as the smallest element, you would have anti energy, and anti matter. So E=MC^2=Plankxel? It would explain were the anti matter is because it is in the smaller form anti time at the edge of the expansion of the universe. This grid constrains infinity and allows it to calculate. So far size and speed explain the blur on our photo of time space and that can make gravity nothing more than another interpretation, a large size pulling allot of entanglements.
there have been proposals since the fifties to get even 150+ tons into space, project orion for example where you would blast your way out of the gravity well with a series of tiny nuclear blasts. all with technology we´ve had since the fifties and something we could do right now. a civilisation on a super earth could certainly use that to get into space if they were willing to take the radiation risk.
Currently dark energy is thought to be Einstein's cosmological constant, so it is expected to continue to accelerate the expansion of the universe. Of course it could have a different behaviour in the distant future but there is little evidence, so far, for it being any more complicated than that (such as Quintessence).
More lagrange point questions! What happens if you have a sun and 2 planets, and the lagrange of one planet overlaps another's? E.g. sun-planet L3 = other sun-planet L3? Or L4 = L5? Would this allow say 2 planets with the same orbit? Or just mean 1 of the legrange points makes another non existant?
A planet could very well be another larger planet's trojan, if that's what you're asking about. However there needs to be a significant mass difference for the system to be stable, with the "main" planet being at least 10 times as massive as the "trojan" planet. If they're too similar in mass the configuration will eventually break apart.
The new frontiers in understanding space, space travel and traversing dimensions is not currently within the scope of human understanding, because the language is not there. Nothing is new, it’s simply to know the medium of operation. One must essentially be willing to let go of what you know and to be more expensive in the approach. Much is waiting to be understood. Your world in not the only world. Neither are your species the only one, even in it’s solar system. There is much to be revealed the time is at hand.
Tatoonie Hilarious... Dark energy must push the ripples on my pond as well as the echo of thunder through the mountains. LMAO I'll have some of what he's having/I remember my first beer.... 🙄🤔
I know the idea you mention, but it is FAR easier to just slump a sheet of glass into a mould to get a fairly large primary mirror (say 600-800mm dia). MUCH lower temperature/cost, readily available glass blank (e.g. an old/thick glass coffee-table etc), you can easily grind 'plaster' mould(s). Relatively small amount of grinding/figuring is needed compared to grinding a large/solid blank (also the shear the cost of such blanks at 600-800mm). This technique really is useful for deep curvatures, as in deep-sky scopes. There's plenty of you-tube content on this method.
As PBS Space Time explains Dark Energy - space is not expanding locally because the curvature caused by Dark Energy is overcome by the curvature caused by mass.
Hi Fraser! I have a question for you! The Universe has been expanding since the Big Bang, so would there be stars at the very edge of the Universe where, if any living being would look at the night sky on their planet, they wouldn't see anything on one side, but would see stars on the other side. Would there be a whole area of the sky full of nothingness? Would it be even black? How would the edge look like according to current hypothesis?
The universe should look the same everywhere, and the 'edge' is only defined by how long the light from there has been travelling towards us. If you lived in a galaxy 45 billion light years away (at the edge of the galaxy from OUR point of view) the universe should look the same in every direction, and the location of the Earth would be at the 'edge'. The universe is thought to be far bigger than we can see although maybe not infinite. If the universe does have some finite size then an 'edge' would not make any sense and so scientists theorize that it is more likely that the universe eventually curves back on itself in some unknown way.
Question: Matter/mass creates gravity/space time bending, right? Ok so the opposite would be nothing occupying empty space, so is it possible the more nothing & larger areas causes an outward push opposite of how gravity pulls inward towards the mass causing it? I hope it makes sense as I've even confused myself but know what I mean. Thanks in advance folks. Stay blessed, peace
Dark energy can be used to prevent the universe from collapsing in on us. It is really easy. I love the theory that the observable universe and what lies beyond is a 5D donut with a big bang at the center. If that is true then something about that shape formation is the origin of dark energy. I am assuming there are many more donuts and other baked goods in the universe of universes. I want to use the word universe to mean absolutely everything but making an exception here.
QI have been interested in the wanderings of photons from the suns core. Another question is the speed of gravity. If the sun was to disappear, would it take 8minutes to effect Earths orbit. or would Earth instantly sling out of the solar system. Taking the moon with it.
Will the Shed telescope's twin mirrors act like an Event Horizon, between your friend's garage and yours? When will we see first light? I bet before SLS launches How long to take the hard drives back to civilization? So many questions..
NASA Artemis site has excellent graphic summary of Mission 1. NASA Artemis summary graphic describes Distant Retrograde Orbit (#11) as being 'half or one and a half revolutions in the orbit period' around the moon. What will determine which number is used?
Hey Fraser on very massive stars that have a life span of a few million years, will the light from the core only "leave" the star when it explodes? or never if it collapses to a black hole? does that contribute to the reason a super nova is so bright, that there is so much light "trapped" inside?
Question. If Pluto isn't a planet (proper, that is) due to it not clearing it's orbital path of debris, and Jupiters Trojans ie. Debris in orbital path, then Jupiter isn't a planet, right? I mean not to split hairs, but I call em like I see them, and that the same side of the same coin. So, wazupwithat?
The thing is, methane is infinite, or rather more specifically, immortal. As long as the cycle of life continues, so will the production of methane, which has what you would call "potential" energy. We will never run out of methane, until we run out of lifeforms.
Is the holographic theory of comology corolated to hawking radiation? Do black holes radiate entangled photons? So maybe we can see inside black holes?
Hi Fraser, why not just look for magnetospheres on exoplanets, since this determines the basis for ultimate developement of life. Magnetospheres required for holding onto atmosphere, which is required for liquid water, which inturn is a required for life.
Depending on the planet and other conditions a magnetosphere isn't always required to hold an atmospere. For mostly rocky planets fairly close to some stars a magnetosphere certainly helps retain an atmosphere, at least for a significate time, but its not an absolute essential.
Maybe dark energy is actually an energy vacuum, with more and more of the lack of anything that space is expanding into drawing more more as space exponentially expands
This might be more of an Isaac Arthur question, but to piggyback onto the question about leaving deeper -sucker- gravity wells than ours, could a civilization reduce the mass of its planet by mass-driving mass off its surface from different locations, ie, shooting material off a giant ramp for centuries until the gravity is reduced enough, and people have had time to evolve to survive in the lessened gravity?
In theory sure, but that would require an insane amount of energy. Also, you can't kick mass off your planet with a single boost. You need to circularize the orbit or it's coming back down, unless you can hurl it so far that it escapes the system entirely.
I took a cosmology course by a Nobel laureate and the question of dark energy still seems backward to me. Most objects in the universe have extreme momentum in their own time direction and spatial expansion is a requirement of time. Imagine a circle where time is the radius and its circumference is space, the circle necessarily grows in circumference as time ticks and objects stationary with respect to the background move outward from the center with a constant argument. The same is true in hyperbolic space-time, it just isn't as obvious when you've turned that circle inside out. I can imagine gravity retarding such necessary expansion somewhat but the mechanism for that involves changing the rate at which time ticks and I'm pretty sure the invariance of 4-volumes means that's also built in to the geometry and the tick rate is increasing (the minimum distance between two events at the same spatial location is decreasing) as space expands. If you are curious about what I meant by the circle turning inside out, try animating x²-ky²=1 as k goes from -1 to 1 in Geogebra to see a transform from Euclidean to Minkowski in action. As for the rest, Hubble's law is essentially built in to the relationship between cosh and sinh as they are each the derivative of the other. The same with cos and sin except for a sign difference.
Hi Fraser, thank you for making awesome content! I just bought my first telescope and I was wondering, if you could give us sort of a checklist of things to look out for when taking the telescope fresh out of the box to see if everything is ok or if perhaps important parts are damaged (lens,mount etc.) and one ought to request a refund or exchange?
Your Star explanation is going to confuse some people because they are going to think planets are all formed from just hydrogen and helium.. I know that wasn’t the intention but not everyone understands the formation of elements.
Hey Fraser! when we talk about gravity we say 1G and compare everything with this, but shouldn't we using another "metric" using mass? regardless, what is the minimum amount of G (essentially the mass) for life to evolve/function? or rather, the range (i.e 0.4g- 3g)
Although mass and 'g' are related (via density and proximity) they are NOT in reality 'essentially g = mass'. There is no minimum/maximum limits to the level of 'g', as you put it, except for VERY high pressures/temperatures where life could not theoretically evolve/function. Zero-g through millions/billions of g alone are not limiting factors.
Dear Fraser big fan of your work. Always grateful for you being a huge contributor in space exploration. Could you explain us why didn't Fritz Zwicky received well when he came forward with the idea of Dark matter in 1933 ? As I've heard it took almost 40 years for mainstream to welcome his idea. If that's true there could exist some ideas which are not hugely received or widely ignored as of today, may come out with more evidence in the future, right? Love to know your opinion about this. Peace.
If mass increases significantly when objects approach the speed of light, what happens when a star is collapsing at close to the speed of light. And what happens when stars are merging at the speed of light.
Since galaxies are hundreds of thousands of light years wide, Is the light coming from the furthest edge of nearby galaxies, thousands of years older than the light coming from the edge that is closer to us?
Dark. Broca's area, or the Broca area is a region in the frontal lobe of the dominant hemisphere, usually the left, of the brain with functions linked to speech production.
The degree of 'g' doesn't automatically mean more or less atmosphere, Earth has a surface 'g' a little higher than Venus (Venus 0.91 of Earth g), but a much smaller/thinner atmosphere than Venus. Saturn 1.08 surface gravity of Earth, but gigantic atmosphere. Back to school, Kyle.
24:00 I haven't done the math, but this is not guaranteed. Yes, you can plug a different G into the rocket equation. But does material science allow a rocket to escape planet 2G? Maybe not!
When you see those big nebulae, they're mostly primordial hydrogen and helium leftover from the Big Bang. It's enriched by heavier elements, but there's no way to know how many.
Dark energy behaves like anti-gravity doesn't it? Maybe gravity actually emits both gravity and anti-gravity, push and pull, whose ratio is determined by some fundamental principles.
Hello Fraser, I am wondering if space oceans are possible. we see huge columns of gas could water behave like this and form huge bodies of water without a planet?
@Tom's Cubes While yes there are numerous chunks of ice out there I am wondering about liquid water not on a moon or planet but spans of water that may have been warmed to a liquid state and formed oceans in space.
I think you mean a bubble of water and nothing else just sloshing around out there. Well *wave* goodbye to waterworld ... First off It would have to be big, big enough that gravity greatly exceeds the vapour pressure of water, ( cold water boils in a vacuum, ice sublimes) and it would have to be a moon or have a moon to create the tidal heating to keep it warm enough without needing a star that would blow off the water vapor... All that said , what would provent oscillations from tarring itself apart? I don't think it would be stable for long. Wave goodbye as it were... The big splash a drop in the bucket. To work I think it would have to be so big it's gravity would compress the middle to a solid or include something other than water (like Neptune), or small enough to freeze a crust (like Europa)
I think you mean a bubble of water and nothing else just sloshing around out there. Well *wave* goodbye to waterworld ... First off It would have to be big, big enough that gravity greatly exceeds the vapour pressure of water, ( cold water boils in a vacuum, ice sublimes) and it would have to be a moon or have a moon to create the tidal heating to keep it warm enough without needing a star that would blow off the water vapor... All that said , what would provent oscillations from tarring itself apart? I don't think it would be stable for long. Wave goodbye as it were... The big splash a drop in the bucket. To work I think it would have to be so big it's gravity would compress the middle to a solid or include something other than water (like Neptune), or small enough to freeze a crust (like Europa)
Frasier I think your mis understand the question. So given your observation of the community are there other compellibgr theories they are considering? In regards to the big band.
No, I haven't seen a scientific consensus on any competing theories to the Big Bang. The are a few that like a cyclical Universe, but there's 99% consensus on the Big Bang.
Concerning the "Escaping Gravity Wells" I think Fraser forgot that for instance a "2G" planet might have a much more dense atmosphere (which goes higher) and so it would be possible to launch a rocket from an airplane (a big one). Also a combination of many rockets launched at the same time (for instance hundreds) that could join above and assemble (very fast) something powerfull (when they reach the highest altitude), could do the trick. Perhaps thousands, which then assemble hundreds, then tenths, until you have a single last one that reaches orbit. Of course that would be very expensive and would require a lot technology but feasable I think. Am I missing something? Couldn't that work? Any logical argument against that? If not, some simple math could demonstrate that, I hope.
Your multiple launch idea for overoming more atmosphere falls at the first level. The mass/area of multiple rockets is far less efficient than just building a single multi-stage BFR. Launch from airplane/balloon has more/some merit for getting out of the atmosphere (but these are essentially first stages). Once out of the atmosphere the main issue is gaining enough/final 'sideways' velocity to reach orbit. The 'atmosphere' and 'final velocity' are two entirely seperate issues.
I don't know why but I always drop the "millions" when I'm mentioning large light year distances. For the expanding question, it should be "tens of millions of light years", not "tens of light years". Unless Chad is actually cutting out the millions part to gaslight me so I think I'm going crazy. I'm not crazy, you're crazy!
@Fraser Cain It's perhaps much easier than you might think to escape a high-gravity planet: For example, I developed a fairly inexpensive launch platform for orbital satellites, using weather balloons to hoist said platform approximately 18 miles above the Earth's surface before launch occurs. This kind of system may well be scalable on a planet with much greater gravity.
I've heard you saying "millions". I'm not crazy. My other me heard it too.
Carl Sagan never dropped a "billions"
So if you're curious why someone might ask you a question about the great attractor it's because news as far as astronomy goes is not very good. A lot of the time if you open an article that is ostensibly about some very specific thing it'll start out with a giant generalization about the entire field just to eat up space. It's really awful honestly. Not to say that all science communicators are like that, you're not for instance. But the majority of people when they look up some concept what they get is just some really Bare Bones entry level astronomy
@@johnstrawb3521 Fraser has covered the problem before. Here is a quick summary. To achieve orbit, the vast majority of the energy goes into sideways motion, not vertical motion. A balloon or even an airplane does very little to help this. The biggest savings is avoiding the higher drag of the lower atmosphere. While significant, it is small compared to the total energy required.
If you want to achieve escape velocity straight up, the problem is the max height of a balloon. A balloon can only increase the distance from the center of a planet by less than 1%. This has a negligible impact on the energy required.
Note that you are far from the first to come up with this idea. That is why the calculations have already been done. You are in good company, but sorry it doesn't work.
Fraser, a great show as usual. That said, you might buff on your understanding of grinding a telescope mirror at home. It is nothing like you described. You take two flat circular pieces of Pyrex (not optical glass) and grind them back and forth. Over time, you will find the two flats come together as a PERFECT sphere (bottom glass convex and the top concave(your mirror)). With a very simple device to magnify the mirror surface a 100,000 times, you hand polish a parabolic curve. You can this curve to within 1/4 a wavelength of light. The old guys writing in Amateur Scientist in the 30’s used used flat windshield glass to grind together! When finished, send it off to get silvered. I made one 50 years ago.
LOVE this comment!
Great response to [Bespin] (the big bang question)! Thank you for modelling journalistic integrity and appropriate levels of respect for expertise instead of armchair speculating. I wish there were more of that on the web these days.
It's also important to remember that people can be experts in one thing and know very little about everything else. Subject matter experts could do better in this area too. Unfortunately I can think of some high profile people with PhD level expertise making ignorant public pronouncements about things in unrelated fields, or even closely related fields that they still weren't experts in. That only degrades public trust in expertise in general and promotes crackpottery/conspiracy theories. Experts: it's okay to say you don't know something!
Okay, I'll get off my soapbox now.
Point in case, he made it really clear he knows squat about telescope mirror grinding. ;-}
1st time watching your video, but I like how it's not annoying dramatic. I see a lot of these videos mentioning TERRIFYING this or that. Space isn't terrifying its Beautiful! Like the creation of a Star, it's an amazing and wonderful process. Other part I enjoyed about your video is accuracies. A lot of TH-camrs hear of an idea one scientist has and they try and make it way more crazier and scary sounding, so they get views. Our Universe is amazing already you don't need to up "Amazing" Thanks again!
Bespin
That was the best explanation of Scientific Method, and correct skeptical balance for Argument from Authority to be respected.
Its quite a while that I watched your show, mainly no time on my side, I see you are still great presenter with great answers
Welcome back!
The launch was awesome! I am always amazed at the precision of all space missions, especially the longer range ones or ones with multiple flybies. Would you talk a bit about how they make that happen, how they have taken something so complex and made it into something seemingly simple with such a high success rate and precision?
I love it when I find an episode I've missed!
Fraser: "I'm just a reporter". Okay Buck Rogers, keep makin' stuff up! (Peter Griffin)
I'm just a simple journalist man. This space stuff is way too complicated for me...
@@frasercain Hey simp. Why limit your answer just to 'space stuff'?
I was about to ask you my question but decided to watch the video again and got my answer. Thank you Frasier Cain
Thanks for all the answers, Fraser! 😊
Stay safe there with your family! 🖖😊
BTW, voting: Tatooine
Bespin, hi Fraser. Great answer to the B.B. question! Would that everyone had your sense of humility.
'i am not educated enough to have an opinion' - such a wonderful insight, such a shame people generally don't possess the humility or the self-awareness to reach the same conclusion. nowhere is this shortcoming more obvious than on social media. and so, my vote goes to Bespin. by a light year.
We need to learn if its an isotropic universe or not. We thought we knew but now the measurements makes this the #1 priority. We can't even ponder things without this being known .
Bespin - awesome information! Thanks for the insight :-)
Glad you enjoyed it!
The whole idea of collision-less matter is interesting. Now harvesting collision-less mass? That's a bit further ahead. Maybe we can understand how it orbits and interacts with black holes first? What dimension to you need to be in to see their interactions sans spacetime geodesics? Is there a higher dimensional model that is even close? I know string theory can tease out DM but that's the problem with it. It can tease out a lot of things which can't be not just directly measured but can't be inference measured either with the physical tools we have so far.
Coruscant:
Brings up a question I've wondered about, how close are the stars in globular clusters to each-other?
About the same, around 1 light-year apart.
Dumb question. They are as close as they are. Measure/calculate the answer, or look it up.
Tatooine
(More of an Answer than a question:)
Unicorn Tears are harvested using Butterflys,
it is well documented.
Of course, I should have known that.
Bro, your answer on the Big Bang question was really good. Wish all journalists had that kind of objective view of their job instead of trying to craft things. Just the facts ma'am. O7
Great answer to the Big Bang question
11:00 From the perspective of the photon, from the moment it was created, it hit your retina and was processed by your brain. Since photons move at the speed of light, time is stationary. Even though it took as many as millions of years to make it out of the sun, it simply was; then it wasn't.
Awesome, thank you for your research and informative, well presented videos!
Observations indicate that the observable universe is expanding at an accelerating rate, what is the current thinking of the universe in its entirety. Assuming that the universe in its entirety is infinite in size, it matters not if it is expanding , contracting or remaining static, it will always be infinite in size and must always have been.
Bespin for sure
Such an interesting topic
How can we know anything? It's difficult to find a perfect answer. 99% of all experts can be wrong, but they usually aren't.
I just love the truth of what you say that is brilliant.
Bespin, great answer
Strictly it is or may not the same photon which is given of by the gamma radiation. Once it is absorbed by an atom it becomes part of that atom. That atom may not give of a photon but if it does it will not be the same photon. 🙂 You said this just as I was writing it
How many years would humanity need to wait until we are on the correct side of the galaxy to start observing the Great Attractor in greater detail, perhaps in visible light?
About 125 million years to get to the other side. But we could probably start getting a better view in 60 million years or so.
Here’s a question I hope you will answer Fraser. My 4 year old asked me why the moon is out some nights and not others. And sometime’s it’s out in the day. I’m not sure how to answer her… I know the earth spins and sometimes the moon is on the other side, but what is the pattern?
The Moon needs 28 days to complete an orbit around Earth. Also, is tidal locked to her, so The Moon always shows the same face to us. See, for example:
th-cam.com/video/arvOgLpfucE/w-d-xo.html
The answer is, your 4-year old daughter is already way smarter than you. ;-)
7:30 ......you can never ever use up the force of gravity, we just haven't figured out how to harness it correctly as strange as that might sound. And if you do I hope you find the right path out to the light!
I seen somewhere here on youtube that if there was an atmosphere between the earth and the sun, the sound levels at this distance (93000000 Miles) would be about 290 decibels . An incredible amount of energy. Could dark energy be the un-manifested sound of all the trillions of stars and debris throughout the universe ? Imagine the sound of an accretion disk around a black hole! Where does all that energy go if it can not manifest as sound waves?
I need to understand this. I will ask elsewhere. Thanks. :)
question:
if you took a yardstick and put the quantum realm at the 0 inch point and the universal realm at the 36 inch point, where would humans be on this scale of magnitudes? physically speaking? are we closer to the tiny world, or the massive world, or somewhere in between?
Yavin , love your content . Thank you very much
I reckon for the past 300 years people have suspected that space itself is not flat. You can look at the Virgo cluster with a fairly small 16" telescope and clearly see that space is distorted. I think its called weak lensing basically everything in the eyepiece is curved.
Fascinating as usual
What if when you try to pull the quarks apart the glueball size is increased which pulls more gluons into spacetime to maintain the gluon concentration which increases the pull. I believe a significant amount of dark matter is gluons which are part of what I call the QL soup.
Do we have the technology to tug on a quark and see if the weight of nucleus increases? The Quark Lepton soup is outside of spacetime which is just a bubble in the soup.
I appreciate yr answer to Bespin. I will say the avg time to.complete just the PhD is about 10 yrs not including the previous degrees required. It's likely decreased recently for lots of reasons but 3 to 5 yrs would be very fast. Chronicle of higher ed has data available on this subject.
Hi Fraser. Love your work. Do we know how much frame dragging is occurring around galaxies and to what extent it affects the speed at which galaxy arms are rotating? Or in other words, is it possible that the rotation speed of galaxy arms is affected by frame dragging as well as dark matter?
Virtually no 'frame dragging', the field intensity to 'frame drag' is for all practical considerations nonexistant for galactic issues.
Mater can go to Energy and Energy can come from matter, but consider one more level that Energy can go to time space what we define as nothing, but it’s a real tangible thing. From a Plankxel, point of view everything is entangled to some degree. As matter or photons smear across the Plankxel grid like a photograph these elements smear into a sort of wave, but the smear can go into the past as well. This allows for the paradox of creation, but it also allows for the expansion of the universe. So, consider an anti time as the smallest element, you would have anti energy, and anti matter. So E=MC^2=Plankxel? It would explain were the anti matter is because it is in the smaller form anti time at the edge of the expansion of the universe. This grid constrains infinity and allows it to calculate. So far size and speed explain the blur on our photo of time space and that can make gravity nothing more than another interpretation, a large size pulling allot of entanglements.
there have been proposals since the fifties to get even 150+ tons into space, project orion for example where you would blast your way out of the gravity well with a series of tiny nuclear blasts. all with technology we´ve had since the fifties and something we could do right now. a civilisation on a super earth could certainly use that to get into space if they were willing to take the radiation risk.
Hi Fraser! About the heat death, is dark energy is expected to stop and dissipate at some point?
Currently dark energy is thought to be Einstein's cosmological constant, so it is expected to continue to accelerate the expansion of the universe. Of course it could have a different behaviour in the distant future but there is little evidence, so far, for it being any more complicated than that (such as Quintessence).
More lagrange point questions! What happens if you have a sun and 2 planets, and the lagrange of one planet overlaps another's? E.g. sun-planet L3 = other sun-planet L3? Or L4 = L5? Would this allow say 2 planets with the same orbit? Or just mean 1 of the legrange points makes another non existant?
A planet could very well be another larger planet's trojan, if that's what you're asking about. However there needs to be a significant mass difference for the system to be stable, with the "main" planet being at least 10 times as massive as the "trojan" planet. If they're too similar in mass the configuration will eventually break apart.
The new frontiers in understanding space, space travel and traversing dimensions is not currently within the scope of human understanding, because the language is not there.
Nothing is new, it’s simply to know the medium of operation. One must essentially be willing to let go of what you know and to be more expensive in the approach.
Much is waiting to be understood. Your world in not the only world. Neither are your species the only one, even in it’s solar system. There is much to be revealed the time is at hand.
Real nice answer about the big bang!
I'm just a journalist. :-)
Tatoonie
Hilarious...
Dark energy must push the ripples on my pond as well as the echo of thunder through the mountains.
LMAO I'll have some of what he's having/I remember my first beer.... 🙄🤔
Ah yes, but will you remember your last?
I remember searching up a guy who made his own lightweight primary mirror blank, by fusing scrap soda-lime glass together in a kiln. 🤯
I know the idea you mention, but it is FAR easier to just slump a sheet of glass into a mould to get a fairly large primary mirror (say 600-800mm dia). MUCH lower temperature/cost, readily available glass blank (e.g. an old/thick glass coffee-table etc), you can easily grind 'plaster' mould(s). Relatively small amount of grinding/figuring is needed compared to grinding a large/solid blank (also the shear the cost of such blanks at 600-800mm). This technique really is useful for deep curvatures, as in deep-sky scopes. There's plenty of you-tube content on this method.
As PBS Space Time explains Dark Energy - space is not expanding locally because the curvature caused by Dark Energy is overcome by the curvature caused by mass.
Hi Fraser! I have a question for you! The Universe has been expanding since the Big Bang, so would there be stars at the very edge of the Universe where, if any living being would look at the night sky on their planet, they wouldn't see anything on one side, but would see stars on the other side. Would there be a whole area of the sky full of nothingness? Would it be even black? How would the edge look like according to current hypothesis?
The universe should look the same everywhere, and the 'edge' is only defined by how long the light from there has been travelling towards us. If you lived in a galaxy 45 billion light years away (at the edge of the galaxy from OUR point of view) the universe should look the same in every direction, and the location of the Earth would be at the 'edge'. The universe is thought to be far bigger than we can see although maybe not infinite. If the universe does have some finite size then an 'edge' would not make any sense and so scientists theorize that it is more likely that the universe eventually curves back on itself in some unknown way.
Question: Matter/mass creates gravity/space time bending, right? Ok so the opposite would be nothing occupying empty space, so is it possible the more nothing & larger areas causes an outward push opposite of how gravity pulls inward towards the mass causing it? I hope it makes sense as I've even confused myself but know what I mean. Thanks in advance folks. Stay blessed, peace
Dark energy can be used to prevent the universe from collapsing in on us. It is really easy.
I love the theory that the observable universe and what lies beyond is a 5D donut with a big bang at the center. If that is true then something about that shape formation is the origin of dark energy. I am assuming there are many more donuts and other baked goods in the universe of universes. I want to use the word universe to mean absolutely everything but making an exception here.
QI have been interested in the wanderings of photons from the suns core. Another question is the speed of gravity. If the sun was to disappear, would it take 8minutes to effect Earths orbit. or would Earth instantly sling out of the solar system. Taking the moon with it.
i didnt kno what the great attraction was. thank you
Will the Shed telescope's twin mirrors act like an Event Horizon, between your friend's garage and yours?
When will we see first light?
I bet before SLS launches
How long to take the hard drives back to civilization?
So many questions..
NASA Artemis site has excellent graphic summary of Mission 1. NASA Artemis summary graphic describes Distant Retrograde Orbit (#11) as being 'half or one and a half revolutions in the orbit period' around the moon. What will determine which number is used?
Hey Fraser
on very massive stars that have a life span of a few million years, will the light from the core only "leave" the star when it explodes? or never if it collapses to a black hole?
does that contribute to the reason a super nova is so bright, that there is so much light "trapped" inside?
No, the light still gets out sooner than the lifetime of the star, but I don't know the exact amount. They're bright, so we know light is getting out.
Is it just a coincidence that Artemis launched when Fraser was disconnected from the web and unable to jinx it? ...Maybe.
Question. If Pluto isn't a planet (proper, that is) due to it not clearing it's orbital path of debris, and Jupiters Trojans ie. Debris in orbital path, then Jupiter isn't a planet, right? I mean not to split hairs, but I call em like I see them, and that the same side of the same coin. So, wazupwithat?
The thing is, methane is infinite, or rather more specifically, immortal. As long as the cycle of life continues, so will the production of methane, which has what you would call "potential" energy.
We will never run out of methane, until we run out of lifeforms.
What happens to the energy that light loses as it slowly expands to longer wavelengths on a trip through space?
Does dark energy only expand the three dimensions of spacetime or does it expand time also?
"We've harnessed dark energy!" And _that,_ kids, is how a grabby civilization causes the "Big Crunch".
Good show!
Is the holographic theory of comology corolated to hawking radiation? Do black holes radiate entangled photons? So maybe we can see inside black holes?
sooo, what would a star look like before the photons make it to the surface? A huge black ball?
Hi Fraser, why not just look for magnetospheres on exoplanets, since this determines the basis for ultimate developement of life. Magnetospheres required for holding onto atmosphere, which is required for liquid water, which inturn is a required for life.
The answer is this: how _do_ you look for an exoplanetary magnetosphere? There is at least one answer, but it's only been tried recently.
Depending on the planet and other conditions a magnetosphere isn't always required to hold an atmospere. For mostly rocky planets fairly close to some stars a magnetosphere certainly helps retain an atmosphere, at least for a significate time, but its not an absolute essential.
Maybe dark energy is actually an energy vacuum, with more and more of the lack of anything that space is expanding into drawing more more as space exponentially expands
Let's focus on Terra. I really like the stellar stuff though.
Holy Terra
18:36 I think a lot of science channel subscribers need to hear this and humble down
Or maybe I'm just less educated than they are. There are plenty of subscribers who have PhDs in various fields and know what they're talking about.
Has all of space stopped inflating or is it still going on today somewhere outside the observable universe?
This might be more of an Isaac Arthur question, but to piggyback onto the question about leaving deeper -sucker- gravity wells than ours, could a civilization reduce the mass of its planet by mass-driving mass off its surface from different locations, ie, shooting material off a giant ramp for centuries until the gravity is reduced enough, and people have had time to evolve to survive in the lessened gravity?
In theory sure, but that would require an insane amount of energy. Also, you can't kick mass off your planet with a single boost. You need to circularize the orbit or it's coming back down, unless you can hurl it so far that it escapes the system entirely.
@@frasercain Thanks! I always forget about that "second kick".
@38:47, Thank you!
For me, the best was MANDALORE this time
I took a cosmology course by a Nobel laureate and the question of dark energy still seems backward to me. Most objects in the universe have extreme momentum in their own time direction and spatial expansion is a requirement of time. Imagine a circle where time is the radius and its circumference is space, the circle necessarily grows in circumference as time ticks and objects stationary with respect to the background move outward from the center with a constant argument. The same is true in hyperbolic space-time, it just isn't as obvious when you've turned that circle inside out. I can imagine gravity retarding such necessary expansion somewhat but the mechanism for that involves changing the rate at which time ticks and I'm pretty sure the invariance of 4-volumes means that's also built in to the geometry and the tick rate is increasing (the minimum distance between two events at the same spatial location is decreasing) as space expands.
If you are curious about what I meant by the circle turning inside out, try animating x²-ky²=1 as k goes from -1 to 1 in Geogebra to see a transform from Euclidean to Minkowski in action.
As for the rest, Hubble's law is essentially built in to the relationship between cosh and sinh as they are each the derivative of the other. The same with cos and sin except for a sign difference.
Hi Fraser, thank you for making awesome content! I just bought my first telescope and I was wondering, if you could give us sort of a checklist of things to look out for when taking the telescope fresh out of the box to see if everything is ok or if perhaps important parts are damaged (lens,mount etc.) and one ought to request a refund or exchange?
Your Star explanation is going to confuse some people because they are going to think planets are all formed from just hydrogen and helium.. I know that wasn’t the intention but not everyone understands the formation of elements.
I've been gone a few days, Fraser. I'm catching up on your videos.
lmao who asked?
@@bradc8420 I am sorry to be so presumptuous.
If it’s a thing but it might be a field or something else all together. It’s not much but it’s infinitely produced.
Gordon Waite has videos on how to make telescope mirrors
Hey Fraser! when we talk about gravity we say 1G and compare everything with this, but shouldn't we using another "metric" using mass?
regardless, what is the minimum amount of G (essentially the mass) for life to evolve/function? or rather, the range (i.e 0.4g- 3g)
Although mass and 'g' are related (via density and proximity) they are NOT in reality 'essentially g = mass'.
There is no minimum/maximum limits to the level of 'g', as you put it, except for VERY high pressures/temperatures where life could not theoretically evolve/function. Zero-g through millions/billions of g alone are not limiting factors.
Dear Fraser big fan of your work. Always grateful for you being a huge contributor in space exploration. Could you explain us why didn't Fritz Zwicky received well when he came forward with the idea of Dark matter in 1933 ? As I've heard it took almost 40 years for mainstream to welcome his idea. If that's true there could exist some ideas which are not hugely received or widely ignored as of today, may come out with more evidence in the future, right? Love to know your opinion about this. Peace.
If mass increases significantly when objects approach the speed of light,
what happens when a star is collapsing at close to the speed of light. And what happens when stars are merging at the speed of light.
Mass doesn't increase when objects approach the speed of light, RELATIVE mass increases, same for time & length.
Hoth
Are Red Dwarf Stars, being fully convective, blasting Gamma Ray Photons, as well as solar wind particles?
Since galaxies are hundreds of thousands of light years wide, Is the light coming from the furthest edge of nearby galaxies, thousands of years older than the light coming from the edge that is closer to us?
Dark. Broca's area, or the Broca area is a region in the frontal lobe of the dominant hemisphere, usually the left, of the brain with functions linked to speech production.
Nope, not unless your brain is in backwards.
Mustafar-- if you have 2-3g your atmosphere is way denser. So balloons and aircraft first stages would be more attractive.
There are also really tall mountains to exploit....
The degree of 'g' doesn't automatically mean more or less atmosphere, Earth has a surface 'g' a little higher than Venus (Venus 0.91 of Earth g), but a much smaller/thinner atmosphere than Venus. Saturn 1.08 surface gravity of Earth, but gigantic atmosphere.
Back to school, Kyle.
24:00 I haven't done the math, but this is not guaranteed. Yes, you can plug a different G into the rocket equation. But does material science allow a rocket to escape planet 2G? Maybe not!
Mustafar
Such a civilization might be more motivated to "bend" the laws of physics and create small wormholes to escape their world though. #optimism
You need to find dark E before any harvesting can happen.
Hey Fraser
how many stars need to die in order to create something like the eagle nebula?
When you see those big nebulae, they're mostly primordial hydrogen and helium leftover from the Big Bang. It's enriched by heavier elements, but there's no way to know how many.
@@frasercain so is there enough material to create stars from big dead ones, or are these nebulas will remain like that forever?
:D what would happen if we used a hydron collider to collide dark matter and dark energy
It would be nice if we could harvest things like dark matter, dark energy, the infinity stones and pixie dust.
do red dwarfs have the random walk?
Dogobah - Turtles, all the way down. :)
Dark energy behaves like anti-gravity doesn't it? Maybe gravity actually emits both gravity and anti-gravity, push and pull, whose ratio is determined by some fundamental principles.
Expertise does not matter.
Evidence matters.
Hi Fraser is the "photo random walk" within a sun's core analogues to the "total internal reflection" proposition for a suns core?
Hello Fraser, I am wondering if space oceans are possible. we see huge columns of gas could water behave like this and form huge bodies of water without a planet?
It would be very cold, so you'd get an icy shell. You're describing Europa. ;-)
@Tom's Cubes While yes there are numerous chunks of ice out there I am wondering about liquid water not on a moon or planet but spans of water that may have been warmed to a liquid state and formed oceans in space.
I think you mean a bubble of water and nothing else just sloshing around out there.
Well *wave* goodbye to waterworld ...
First off It would have to be big, big enough that gravity greatly exceeds the vapour pressure of water, ( cold water boils in a vacuum, ice sublimes) and it would have to be a moon or have a moon to create the tidal heating to keep it warm enough without needing a star that would blow off the water vapor...
All that said , what would provent oscillations from tarring itself apart? I don't think it would be stable for long. Wave goodbye as it were... The big splash a drop in the bucket.
To work I think it would have to be so big it's gravity would compress the middle to a solid or include something other than water (like Neptune), or small enough to freeze a crust (like Europa)
I think you mean a bubble of water and nothing else just sloshing around out there.
Well *wave* goodbye to waterworld ...
First off It would have to be big, big enough that gravity greatly exceeds the vapour pressure of water, ( cold water boils in a vacuum, ice sublimes) and it would have to be a moon or have a moon to create the tidal heating to keep it warm enough without needing a star that would blow off the water vapor...
All that said , what would provent oscillations from tarring itself apart? I don't think it would be stable for long. Wave goodbye as it were... The big splash a drop in the bucket.
To work I think it would have to be so big it's gravity would compress the middle to a solid or include something other than water (like Neptune), or small enough to freeze a crust (like Europa)
Frasier I think your mis understand the question. So given your observation of the community are there other compellibgr theories they are considering? In regards to the big band.
No, I haven't seen a scientific consensus on any competing theories to the Big Bang. The are a few that like a cyclical Universe, but there's 99% consensus on the Big Bang.
Bespin 👍
Concerning the "Escaping Gravity Wells" I think Fraser forgot that for instance a "2G" planet might have a much more dense atmosphere (which goes higher) and so it would be possible to launch a rocket from an airplane (a big one). Also a combination of many rockets launched at the same time (for instance hundreds) that could join above and assemble (very fast) something powerfull (when they reach the highest altitude), could do the trick. Perhaps thousands, which then assemble hundreds, then tenths, until you have a single last one that reaches orbit. Of course that would be very expensive and would require a lot technology but feasable I think. Am I missing something? Couldn't that work? Any logical argument against that? If not, some simple math could demonstrate that, I hope.
Your multiple launch idea for overoming more atmosphere falls at the first level. The mass/area of multiple rockets is far less efficient than just building a single multi-stage BFR. Launch from airplane/balloon has more/some merit for getting out of the atmosphere (but these are essentially first stages). Once out of the atmosphere the main issue is gaining enough/final 'sideways' velocity to reach orbit. The 'atmosphere' and 'final velocity' are two entirely seperate issues.