Auroras in the South, Restarting Planets' Dynamos, Old People on Mars | Q&A 222
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- Äas pĆidĂĄn 16. 06. 2024
- How can we possibly know everything about exoplanets from just a single pixel? Will Mars be a good place for old people? Where does more emptiness come from if the Universe is expanding? Can we ever get to explore Betelgeuse? Answers to all these questions and more in this week's Q&A!
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00:00 Start
01:43 [Tatooine] How do we know so much about exoplanets from single pixel images?
11:43 [Coruscant] Side windows on Mars greenhouses?
13:09 [Hoth] Is low gravity good for old people?
14:31 [Naboo] How can a planet's dynamo restart after stopping?
16:42 [Kamino] How to explore Betelgeuse?
19:35 [Bespin] Are we expanding with the expansion of the Universe?
21:41 [Mustafar] Does Universe expand or do we shrink?
22:58 [Alderaan] Will far away galaxies fade out of existence?
26:01 [Dagobah] Do solar storms affect the borealis and australis equally?
30:41 [Yavin] What is the Great Attractor?
34:57 [Mandalore] Newest water origin explanation?
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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. - VÄda a technologie
I actually love having random space convos with unpredictable people, it's amazing how much interest there is. †even at the coffee shop! But absolutely amazing point and good awareness for people. Support your favorite channels people â€â€
Excellent, just let me know what you want in your latte.
@@frasercain *sings* You're the creammmmm in my coff-ffeeeee....
@@frasercain Only if I can get you one too! lol
Brainstorming ;)
It is surprising which people are interested in what. Iâve never met a stranger so Iâm always down (time permitting) to have random in depth conversations.
Tatooine
I get this question a lot from people I know. You did a great job answering it.
Thanks, I get it so much. :-)
Tatooine, I liked your reinforcement of the scientific method and peer review processes!
An obvious thought struck me about your Kamino answer.
Betelgeuse would not exist as a red giant by the time you arrived.
It could last for a million years, so it's probably still there.
Tatooine!
I wouldn't have even taken the time to answer that person, but you made something amazing out of you answer! We have to trust all these independent scientists who are skeptically reviewing each others work, at least for fields we're not personally fascinated enough by to read the literature, follow along with the logic, and yes sometimes even do the math. There is a chain of evidence going back to fundamental axioms of math and philosophy, and were thrilled every time we find a weak link in it or a new branch đđ€Ż
Tatooine - I have 2 master's degrees and a doctorate in a field far, far away from what we are looking at here (Theology and Psychology) but have learned how to learn. At 66, I started to review mathematics again so I can understand a bit more of what physicists are talking about. The human spirit (oops, sorry that's controversial) cannot be broken by facts, only enriched. I would encourage anyone who wants to understand to do the work. Who knows? You yourself might well contribute to the foundation of knowledge that we all stand upon. On a personal note, I would not mind being sent to Mars to work on our civilization's foothold. This life's end is a certainty, but that doesn't mean we can't still contribute in our own ways to progress, no matter our age!
I feel that our progress as humans needs to be done (or significantly advanced) here on Earth before we shift our focus to distant very inhospitable locations. If not, we are only dragging our garbage around the solar system.
As for technology improvements (I'm all for them), that will come, but will it progress our race by some untold way? It hasn't thus far.
I was actually thrilled by an incredible display of the Auroras Australia recently. And yes there was a transcendent moment. It was 5am and the crimson southern sky was lit up with ever moving screamers, almost like search lights, with added bonus of a meteor shower in the middle of it. I watched for almost an hour, gasping at the sheer wonder of it. I saw a comet last year and now this...two things off my bucket list.
Thanks for your calm & clear explanations.
Tatooine!
Another area of science that uncovers unimaginable detail from fragments of information is geology! One of my favorite examples is the dating and describing of volcanoes in history from tree rings. The size and composition and date of volcano ash clouds can be well defined by the tree rings (including fossilized trees) So cool!
Thanks for all the great content Fraser.
I just want to thank you for the great content you put out, you do amazing work.
Thanks a lot!
Holy crap Fraser, Tatooine! That answer was incredible. I want to show it to all of humanity.
Hah, great. I'm glad you enjoyed it. :-)
Fraser, I have to say this. I absolutely love you and your entire team for bringing out such wonderful space related content every week! My life is actually made better because of it! I will support you in every way I can and next time I am in Vancouver island Coffee is on me!
I live in Alaska and I second the position that if you never have seen the aurora than you should figure out a way to make it happen. If you don't live in good place for aurora, make a point to travel to one (like Iceland, Norway, or Alaska) during the right season at some point in your life.
Tatooine!
Thanks for the video, Fraser! đ
Stay safe there with your family! đđ
Yavin, great question, brilliant answer, that explained something not often covered.
Incredibly, it's once again Tatooine đ
Mustafar - this episode was aweome, thanks, Fraser and patrons!
Thanks a lot
Coruscant - 1 meter of water above will do the trick, especially if protected by 10+cm of glass & held up by another 5-6 cm of glass⊠The mirrors & or LEDâs could provide extra light to encourage growth, especially if youâre planting on racks.
Really enjoy all of your videos.
I couldnât get past Florida Manâs question due to the hilarious profile picture, yet you managed to soldier on without breaking character. Impressive! Regardless, I give the edge to the answer given on Tatooine. Thanks for another great Q&A show!
He's posted a bunch of questions, so I'm accustomed to it. đ
One of your finest. Encouraging our support for our interests and then taking the time to explain how scientists are working hard to give the rest of us knowledge.
5:45 Beautiful answer. And also, even more specifically at their question, there are usually countless photons of all different colors in the area of a 'pixel'. A screen _averages_ these colors into a single pixel color, while a spectrometer instead _spreads out the colors more_ , allowing one to see them. So the astronomers aren't using the pixel as much as all that data that went into the pixel.
Tatooine. I'm a big believer that science is only just beginning to mature. Every huge civilization looked up to the stars for more understanding, but they had no idea how complicated everything turned out to be. Science fiction couldn't have thought of a more terrifying enemy than regolith for example.
Now we have these tested models and we can actually look at the sky to do science. The next chapters of science is to catalogue everything around other stars, actually spreading life to other planets to diversify, making the universe alive one step at a time because life is the ultimate science subject.
I think you should do one episode a year where it's your questions and our answers. It gives you a chance to laugh at "our" (the general publics) ideas on how things work.
I think that would be good, I myself have lots of ideas worth a laugh.
Hah, I like that idea. I wonder how we'd actually do it.
â@@frasercain do a small video where you ask lots of questions based on the kind of things said in comments etc, invite answers through email or via comments or a specific means.
That'll do.
â@@frasercain Easy, just read comments under your videos. The fields are rich.
Another great episode man, miss taking part in the live shows but kids
I grew up where spectacular vibrant dancing green northern lights were just the normal sky at night.
Tatooine. A very good way to describe the essence of the scientific method for those that are sceptical of scepticism (yah, pun intended). Especially how you ended with wouldn't the world not be a better place if more people embraced the idea of having random ideas backed up by evidence.
Thanks, I'm glad you enjoyed it. I keep practicing my science pitch. đ
Yup, Tatooine. Science is the best light in the darkness we've discovered. People who can't grasp that need to hear explanations like Fraser's.
I like the idea of Mars being the new Florida. Old people as far as the eye can see. On the opposite side It makes me wonder what planet all the young people would choose to attend Spring Break.
How does chemistry occur in space? Things like water and complex organic compounds seem to be ubiquitous in space matter. So how does water and complex molecules form from the elements produced in supernovas interacting / collapsing together?
Tatooine. Because? What you say needs to be repeated and repeated until people grasp and understand these concepts! Mahalo, Fraser!
TATOOINE! A wonderful defense of the scientific method! Well done, Fraser!
Thanks!
That horse teeth example was certainly an unexpected analogy đ
Great job your doing đđđ
Beautiful description of the scientific method for the uninitiated Fraser. Nice job.
tatooine, great way to explain the scientific method and why it is so important
Thanks! I'm glad you enjoyed it.
great show. thanks
Thanks a lot!
Tatooine: what matters is not what you know, but how you know what you know.
I hope the person who asked that question stuck around to the end of the answer.
8:45 I want to add: and you can also do many of these things yourself. Buy/make a telescope, learn how to use it and how to calculate things yourself. Then do it yourself. And you will understand and will be able to check things yourself, in case you are curious. Here in my country university is free, so you can sign in and take as many lessons as you like and/or participate in real science experiments and observations. And there are also a lot of hobby clubs and hobby science communities or other opportunities (like visitor days at observatories, ok maybe more "visitor nights") to take a look for yourself. Science is build on human curiosity. Use it.
Great show Fraser! I vote for Kamino!
Thanks!
The most current MRI scanners have a magnetic field of 14 Tesla.
Put one of these, without shielding as we put them on Earth, in space at the Mars L1 LaGrange point (between Mars and the Sun).
Connect to a SMR (small nuclear reactor) for a constant power supply or a power supply that has to be changed/updated every 50 to 100 years.
This would put a Magnetic 'bubble' Field covering all of Mars making it safe from the Solar and Cosmic Radiation. :)
We could also put one on the Moon/Luna and give the Moon a Magnetic Field.
I'd volunteer to try out living on Mars when I'm old.
Hi, You always talk about the cosmic rays. is there a way you could harness the power of those rays like a solar panel or another device that would capture the power that those regenerate?
we have auroras here in idaho. but they dont happen frequently. when they were here a couple weeks ago it was overcast so we couldnt see them
Yavin! The answer to The Great Attractor đ
Great fun episode FraserâŠđ
Hi Fraiser, If we where to explore planets in the future where we want to live, stay/work. What sort of planets would we be looking for. I was thinking of a planet with water, so you can shield yourself and have everything you need to survive fuel/food. Could you give your opinion and elaborate. thank you so much for a brilliant channel.
Like Earth, right? You go, I'm staying here. đ
which way do we look to see where the voyager spacecraft are heading? like i want to point at them : )
Perhaps, our planet acquiring its moon gave us plate tectonics, a Dynamo, oceans too, and tides. All due to the type of collision with Thea: a possibly water-rich dwarf planet originally from out past Jupiter, sent our way by the Jovian lord.
In short, blame it on the moon, Thea & Jupiter.
I agree
Yavin - My question is about Pluto and Charon. Since they are tidally locked and orbit a common center of gravity that is above the surface of Pluto, if you stood on the opposite side of Pluto from Charon, would you feel a different sensation of weight than you would if you stood directly below Charon on Pluto's surface?
Yavin - I didnât know the great attractor was a solved problem, thanks Fraser!
Yeah, maybe 20 years ago?
When spacecraft sent to an L1, L2 and L3 point reach the end of their mission, is the remaining propellant used to send the vehicle on a different trajectory or are they just left to drift off uncontrolled? If propellant is used what is the trajectory? If itâs allowed to drift what direction/ orbit do objects tend end up in?
They drift. They use their propellant to the very end.
Bespin. ... Personal observations force me to conclude that I am getting more dense over time, although I don't expect to collapse for several decades yet.
Hi Fraser. I love the idea of the solar gravitational lens. Could we do the same thing with a black hole and, if, planet 9 turns out to be a black hole could would that make a good telescope?
Ah the answer to Highlander its better to burn out than to fade away : ) Could the expansion of the universe just be an Illusion from a time Dialapse ie. the first 10000 years it seems like the universe is contracting inward and say the next 10000 years it reverses and looks like its spreading apart? My vote is for Tatoonie or however ya spell it. Thank you Fraser for no adds it makes it a lot easier for younger ones to learn without the distractions Much Thanks!
Tatooine: Cogently explained to the lay listener. Five Stars!
Thanks! I'm glad that worked for you.
Love your sentiment â€
The Voyagers used gravity assists to get up to speed. To get to Betelgeuse that way would require it to be aligned a certain way with respect to Jupiter's orbit, and Jupiter would probably have to be in a certain part of its orbit. Do you know whether that's the case?
I'm sure there's a gravitational assist or two that someone could use to get to Betelgeuse, you just have to wait for the planets to align nicely.
An alignment to use the larger bodies could require a years long wait for the window. Unlikely to duplicate the Voyager slingshots without some creative geometry playing the called 4-5 bank 8 ball in side pocket.
Another dellima would be leading the target system accounting for time and distance before departure as well as after. Intervening years BTLGS will possibly burn out or nova in it's death rattle.
Are photographs from telescopes different so that every pixel contains information about all of the frequencies of light hitting it?
For usual cameras, I would think that a pixel only has 1 value for wavelenght represented digitally later as RGB.
How can we tell a difference between the universe is expanding (or us shrinking) and the speed of causality slowly decreasing? Why do we assume it's the former?
(Follow up question to [Bespin] and [Mustafar].)
Great color balance. We have brains that are hardwired to know the physics that mattered to our daily lives through the eons. Leonard Susskind refers to it as "grock". I think it means when you understand/predict things by instinct.
In my understanding, Understanding and Predicting things are two wildly different things. But if Mr. Susskind wants to use one word to describe both, then....
Wikipedia: Grok /ËÉĄrÉk/ is a neologism coined by American writer Robert A. Heinlein for his 1961 science fiction novel Stranger in a Strange Land. While the Oxford English Dictionary summarizes the meaning of grok as "to understand intuitively or by empathy, to establish rapport with" and "to empathize or communicate sympathetically (with); also, to experience enjoyment" [...] Uses of the word in the decades after the 1960s are more concentrated in computer culture [...] "When you claim to "grok" some knowledge or technique, you are asserting that you have not merely learned it in a detached instrumental way but that it has become part of you, part of your identity. For example, to say that you "know" Lisp is simply to assert that you can code in it if necessary - but to say you "grok" Lisp is to claim that you have deeply entered the world-view and spirit of the language, with the implication that it has transformed your view of programming.[...]" A typical tech usage from the Linux Bible, 2005 characterizes the Unix software development philosophy as "one that can make your life a lot simpler once you grok the idea".
Is a black hole a distinct object or is it a phenomenon for when an object gets too dense/massive for light to escape its gravity? Like is there a threshold where a neutron star all of a sudden becomes a black hole? Or is it possible that there is an event horizon at the core of stars and we just canât see it?
I voted for Yavin. The thing is, reading the Wikipedia article on the Great Attractor, it seems the nature of Great Attractor still has some unsolved mysteries.
ughhh, forgot nz again at 27:22
gosh, we even have a dark skies observatory at Aoraki
not to mention Stewart Island etc
Nooo, you're right. I'm sorry. And that's a đšđŠ sorry.
The big difference between Venus and Earth? The Moon keeping the core warm with Tidal Drag.
Q: this is perhaps outside the purview of question time but here goes anyway: I once encountered the ... hypothesis? (perhaps "notion" would be a more accurate label) that the convex curvature of the 3D space we know is due to it being the 3D surface of a 4D hypersphere. I don't much care about the (im?)plausibility of such a conjecture, but I have questions about what it would imply, if true. Would acceleration of the expansion rate not imply that the hypersphere is shrinking, causing the convexity of its surface to increase? And if so, and the acceleration continues, what happens when the diameter of the hypersphere reaches zero? Does the 3D space that we know and love not simply go "poof"?
[Addendum, not part of the question] You'd have a whole lot of matter with nowhere to be... Something exciting would be bound to happen. Perhaps someone more clever and or crackpot than I could build a cyclical universe theory from this. Perhaps they already have?
I believe it is possible to recompile the aberrations seen in gravitational lensed images? Would these images look like the images from a standard telescope and if so are there any examples of this being done before? Maybe if you were at the focal point, the image would look perfectly normal?
The shrinking question made me laugh so hard
We can see the cosmic horizon. However, in the 13.8 billion years the light from the cosmic horizon has been traveling to our retinas, the cosmic horizon has since moved on and is now about 40 billion light years away. So what you're seeing is 40 light years away, but it released the light you're seeing 13.8 billion years ago.
After Mars and its moons, what do you think will be the next celestial body humans go to?
Probably an asteroid or ten.
Dagobah - There are some thing that just can't be experienced fully on a screen which is why I want to see one in person one day. I liken it to experiencing a sky scraper. You can look at the highest of resolution image or video of a sky scraper but it can't be compared to standing at the foot of one and looking up.
Tatooine, Great Answer. I don't know if it will actually work out but one of the hope for a direct connection to AI, like Neuralink, is that it could basically make each and everyone one of us a specialist in all fields. I know that the best outcome is not likely but imagine how much we would learn if height billon people had instant access to all the information humanity has ever learned an be able to test, prove/disprove and imagine new way to use this knowledge.
@Just Looking I edited to add the missing link that could help actually improve the output of : "one of the hope for a direct connection to AI, like Neuralink, is that it could basically make each and everyone one of us a specialist in all fields"
But the danger are also much greater than what we see happening with the internet now. How do you separate all the lies and half truths from the facts when they are all feed directly into your brain.
That is where the Tatooine answer could shine because we could all, hopefully, be able to learn, understand and test all of the steps without having to spend a lifetime to learn part of one field.
Then again, there is no proof that even instant access will brings greater understanding.
We already have the precursor to your Neuralink, it's called the "Internet". Feel free to test, prove/disprove and imagine new ways to use this new knowledge today. If we pass the internet test, then we may go on to hardwire it into everyone. In the meantime, enjoy.
It is the perfect realitivity of big bang theory about to the meta physics.
Mandalore - What if Thea, the planet that crashed into Earth to form the moon, was an icy planet, kicked out of the outer solar system by one of the larger planets?
Hi, could a star or a large object made from exotic matter, exhibiting anti-gravitational properties, make reverse gravitational lense?
7M Y for Voyager 2 to reach Alpha Centory is just insane xD My gosh .... Its actually a realy good idea to take a known underatandable point of reference here on the earth scale (ex:Turbojet,fighter jet or even for harder comparaison),.. compare it to voyager 1&2 to then compared that to the great distance and speed of deep space bodies!!
Question: Which Lagrange Point would be the best place to put a large space station/habitat? Which LP gives the best balance between energy availability and heat radiation? Which LP is likely to have the least "junk" floating around in it? While I would assume a Lunar LP (4 or 5) might be a first try, by the time we look at Earth's LPs, the distance from Earth may make a Venus or Mars LP just as close (at least some of the time) but Venus would have easier access to energy in with perhaps more problem radiating heat.... That may not be true with no convection to take into account (I don't really know). The final part of the question: would a LP be better than something in its own orbit around a planet or the Sun? The biggest advantage to an LP, in particular an Earth LP, would be communication due to the station always being in the same position relative to earth. On the other hand, some thing that crosses our path once in a while may be easier to commute to. There are probably a lot more compromises I have not thought of. Is there someone studying this you could interview?
P.S. I looked really hard to find Lagrange point questions I don't think I have heard before ;)
Is it possible that somewhere there is a planetary system with a black hole at it's center....and maybe one or more planets host life by using residual heat from the planet's formation....heat from radioactive decay...similar to the theory of life in / on rogue planets?
I love science, I really do, math is really hard though,
The math is hard, but it's not necessary to appreciate science. If you wan to do science, it does matter, though.
22:00 I've never heard, "We're all shrinking" Oh My God !!! I now say, AS IF WE FELL INTO A BLACK HOLE, EVERYTHING FALLING "TOWARDS THE SINGULARITY" Faster and Faster exceeding the speed of light and RELITIVISTICALLY faster and faster, smaller and smaller.
NOW we have the perpetual direction of time!!! Down into the black hole, our future!!! THAT SUDDEN SHIFT OF PERSPECTIVE!!! OMG!!!
I have a question that recently popped into my head: If time is relative to speed and time passes slower or faster depending on velocity of an object. How do we know how fast we are actually moving through space? Like our whole solar system with the sun basically dragging everybody with it? Or is every solar systems in our galaxy dragged at the same speed? And what if our whole galaxy moves at a certain speed? How could we know that? And do we see galaxies that move at very high velocities?
And wouldn't that mean, that there's solar systems or galaxies that move really slow through space so time goes away fast and therefor any aliens to develop on there have an advantage to do research, grow big, etc. cause time plays in their favor compared to others?
Thanks for trying to answer if you read this.
I live in Ireland, and we get aurora alerts all the time. I never seen one because I don't bother with the alert. Its always cloudy in here
For Naboo - What is the one common denominator for Venus and Mars that makes them different from Earth as far as a magnetosphere?
They don't have a large moon. Our moon is constantly kneading the planed. Working the mantle and core.
What happens if you put a moon around Mars that is in relational the same as ours. Could the kneading kick start the core?
Just thinking?
My philosophy about how to think is:
1. Put the observation on a pedestal at the center of your mind. It is all that matters. Avoid confirmation bias by starting with an observation, not the search for an observation that fits a pet theory.
2. Then we make theories. They are tools for our mind that grant us ability to predict experiments and realize how we could build things like computers for instance. The merit of a theory should be based on its practical benefit. Never elevate it to a religion. It is like kneeling before a hammer. Theories can be tossed out at any time for a theory that does a better job for us.
Does infinity really exist? If so, then anything and everything we could possibly think of would exist, like parallel universes that are alternate timelines to ours. Thanks Fraser!
Alderaan was a good one! I still have a hard time visualizing this stuff.
Thanks, I'm glad it helped.
[Dagobah] Hey, you missed out on Aotearoa (aka New Zealand)! đ
The hidden continent.
Still the best chapter, closely followed by [Yavin]. Thank you!
Yeah, of course. Sorry about that. :-)
If all our endeavors were driven by curiosity rather than emotional attachment to a belief system then yep, it would be great.
I have a question!
Context: Waves interfere. Opposite amplitudes cancel each briefly when they meet, they then reappear and move away from other. QFT says that particles are waves in quantum field.
Question: Why then particle meeting its antiparticle cause an explosive annihilation instead of brief cancelling?
I think, it is because particles of matter (fermions) interact with each other via forces.
In the case of photons, they don't "feel" each other. There is no force between them.
Every time, energy gets converted into other forms of energy, a force is involved.
Follow up question to the "if you jump on a spinning space station question": If you run, possibly Olympic level speeds in a counter rotation around the rotating space station, would you eventually lose your artificial gravity, to the point where you would find it difficult to get traction as you run? (Traction requiring a downward force, which you lose as you lose the effects of artificial gravity.) Conversely, would you feel heavier if you ran in the opposite direction. What are your opinions on a rotating space station relay race sport?
If the station didn't have fuel and rockets designed to adjust for that, yes, if the runner runs in the same direction all the time, they could decrease or increase the gravity, but I don't think anyone would let that happen. They'd ask the runner to turn around and run the other way after a while. But in theory, yes this could happen, not by jumping, but by running in a circle.
Depending on the mass of the station, it might take a very long time.
@@YTEdy I was thinking more of the following, maybe I didn't word it very well. You are standing in a spinning space station. You go around at say 1rpm. The space station is infinitely heavy and no movements by anyone inside can change its momentum. You experience effectively 1 g because the rotation pushes you toward the outer wall. If you were instead running at -1 rpm around the circle of the station, from an outside perspective, you'd be standing still... or running in place. Because you aren't moving in a circle anymore, what level of artificial gravity would you experience?
Conversely, if you ran along with the rotation, suddenly your angular speed is doubled. Would you therefore experience twice the effective gravitational downward forces?
@@Beldizar That's a cool question. I'm not sure. I'll have to think about that, or ask a friend.
Q.) Bespin: so will it ever stop becoming less dense, and what happens at that point, and thereafter?
Hoth: as an old person already, i would put it out there and say that i (and plenty of other âold people) would be quite willing to go there and provide data for the researchers ;-)
can radiation (like cosmic radiation) be reflected by a mirror? Or other wavelengths of light, such as xray.
Tatooine!!
18:20 Regarding a scientific journey to Betelgeuse: you also forgot the time it will take to receive data and send commands to our probe. It's also unlikely, that we will be able to send and receive a strong enough signal anyway. It's way more rediculous than it already sounds.
All of the universe is expanding at approximately 70km/s per megaparsec. Local galaxies are not expanding away from each other due to the more locally powerful gravitational pull between each other, yet the Universe fabric underneath/around it is still expanding. At supremely large distances does the universe expansion rate exceed the speed of light. So yes, the universe is expanding around us but locally it's just too slow to worry about.
I was curious what effect expansion of the universe would have on the distance to betelgeuce.
Some very very rough calculations.
So according to google the expansion rate is approx 75km per second per mega parsec.
Betelgeuse is approx 0.000131 megaparsecs away.
So that means in 7 million years it will be approx 75*3600*24*365*700000*0.000131 km or approx 0.023 light years further away from us....
In fact given voyagers speed of approx 17 km/s it could never reach something that is more than approx 0.25(815390 light years) megaparsecs away due to the expansion...
If I didn't mess up.
Tatooine!
@Fraser Cain : you said only 4% of the universe is reachable if right now we leave at close to the speed of light.
4% of the volume or 4% of the radius?
If 4% of the radius, then 4% is 1.6 billion LY, correct?
Volume.