Limits of Kardashev Scale, Artificial Stars, Can We Touch Jupiter | Q&A 177

[@johnchilds479]

It's not about running out of room, it's all about earth being far too dangerous a basket in which to leave all of mankind's eggs. As Larry Niven said: "There are things in this universe that are so dangerous the only way to survive them is to be somewhere else when they happen." or words to that effect. And we're not in charge of the timetable. So let's not waste any more time fiddling

[@sciencerscientifico310]

Currently we're just a kilometer meteorite, supervolcano, nuclear war, etc away from extinction or at least not having a civilization. We really need to reduce launch costs such that as many people as possible can go to outer space!

[@jondoc7525]

We will survive governnt has Miles of secret caverns built up.

[@jondoc7525]

@Train 2noplace just makes sense to. Then we can pollute in space and earth will be a sanctuary .

[@dropshot1967]

The advantage of using an external laser is that the thrust it delivers to a sail/spacecraft is derived from absorbing the momentum of the photon as it arrives and getting that same thrust again when that photon is reflected from the sail. Using an onboard laser only works by using it as direct thruster by pointing it away from the spacecraft. That only delivers half the thrust of an external laser though since the first step of absorption does not happen.

[@frasercain]

Yeah, but it does allow you to provide constant thrust, and allows you to control the direction. If you had an infinite source of electricity, you could navigate around. Of course, finding the infinite source of electricity is the trick.

[@lukasmakarios4998]

The Kardashev scale originally was meant to describe the power of advanced civilizations, in particular, those that have achieved the ability of space flight. It uses a geometric progression based on the amount of power accessed by the species as it grows. The earliest emerging civilizations don't appear, except as fractional numbers, because their activity is not very significant on a cosmic scale. These only get a full count when they might be noticed by a theoretical "outside observer," as you will soon see. I am adding a few extra levels to the original three, since there was little use for that as a measuring stick to evaluate gradual progress. Let me start near the beginning, when the culture starts to reveal its potential significance. Type One: "Novice" (revised) intensive use of more than half of the planet's habitable surface area for urban dwelling, agricultural production, industry or resource extractive purposes. Oceans, ice caps and deserts are not typically considered habitable, although some oases may exist. Type Two: "Unstable" (revised) threatening the ecological health of the planet by careless practices, whether by stripping resources, excessive pollution, or loss of secondary species. Type Three: "Emergent" (revised) has acquired sufficient technology to make space flight and colonial ventures possible. Potential for mass self-destruction demands a quest for coexistence. Type Four: "Maximized" (original) Type One: intentional use of all the insolation received by the planet for food or power. (revised) has accessed or made feasible all of the resources and energy available on the planet. Approaching a sustainable global regime for shared resources and political consensus or a tolerant balance of powers. Type Five: "Outbreak" (revised) has established self-sufficient populations, with trade routes, in multiple extra-planetary colonies, and continuing to spread. Industrial development of free-floating habitats, space infrastructure and specialized project construction begins. Type Six: "Established" (revised) has explored the entire stellar system in sufficient detail to map a super-majority of its geography and resources. Technological proficiency allows pioneers to colonize the frontiers at will, and choose political independence. Type Seven: "Expansive" (original) Type Two: intentional use of all of the energy output of the star for habitation and industrial purposes. (revised) complete access to all of the resources and energy available within the star system, including its planets, moons, and smaller satellites. Experimental robotic ships explore the nearer neighboring star systems and the conditions of intermediate space. Type Eight: "Arrival" (revised) first colonies established around other star systems. Ultrahigh-energy physics experiments explore the potential for travel at relativistic or supra-lightspeed velocities. Type Nine: "Manifesto" (revised) seeding the stellar neighborhood with many colonial ventures, discovering the range of variety of system formation and geography, and revealing the frequency of the origins of life. Type Ten: "Epitome" (original) Type Three: acquisition and use of the entire energy output of all of the stars in the whole galaxy. (revised) technological capacity to range at will throughout the galaxy, planting colonies, developing resources and tapping unlimited energy as needed to sustain the presence and growth of the species in all its various iterations. Sophisticated modes of long distance travel and self-contained habitat ships allow for sporadic attempts to surpass galactic boundaries. Conclusion: As you can see, the original version of the Kardashev scale assessing the power use of a space-faring civilization was excessively over-simplified. Having only three tiers, it did not allow for any detail or description of the intermediate stages of development. At every stage, it required an "all or nothing" obvious achievement in order to advance to the next rung of the ladder, and totally lacked any descriptive or predictive powers. This revised version does have more capacity for descriptions, and also allows for a certain amount of flexibility. It can be used to note and measure some fractional attainments, and can accept some skipping and mixing of non-linear development patterns, while still offering some definite levels of meaningful achievement for comparisons. Nor does the new scale have to terminate at the edge of the galaxy, or proceed to such degrees as beggar the imagination. At Type Eleven, the colonization of another galaxy, and at Type Twelve, the colonization of the whole local group of galaxies is enough, while further expansion into the greater Super Cluster and beyond may be designated by more numbered levels. These do however go so far beyond the imagination that those technologies would likely appear magical to our sensibilities. And any further would simply involve the acquisition of the entire knowable Universe. It seems probable that, at some point, even before we claim the far reaches of our own galaxy, we are likely to discover another intelligent, civilized and space-faring species and learn not only whether the scale is truly useful, but have the realization that we must share the Cosmos with our neighbors. And that will be a clear answer to one of the oldest questions we have ever thought to ask. If you wish to adopt and promote this revised scale for the comparison of developing civilizations and space-faring technology, you may be my guest. I ask only that you acknowledge and attribute it to its source, and name it the "Makarios Scale." Makarios means "Blessed" in greek, and any species and civilization that this scale would measure should be well aware of their blessings. And I thank you for your patience and kind consideration. Shalom. I published this in September 2020, in my own obscure little blog: www.emunahechad.blogspot.com

[@ericgolightly8450]

I like it, I could see scientists using it when studying technology and colonization.

[@AndersWelander]

Maybe it is possible to control a star so that it ends up being a lump of iron by feeding it fuel in a way that keeps it from going supernova but keeps it burning until the very end of fusion energy. And have a Dyson sphere around it and make the very most efficient use of all the energy. You also get radiation energy due to the fuel falling into the gravity well as a tiny extra bonus. I can't imagine how fusion reactors would ever work for anything other than fuel that burns very fast, D+T is the fav. The burn rate in a reactor has to at least compensate radiation losses and I can't imagine a way to keep those down much. Radiation losses also go up sharply for heavier ions. In a star the radiation is reabsorbed and doesn't escape.

[@colinhouseworth9027]

I try and catch the live q&a show but usually I’m working. Glad you post these and interviews as well.

[@miinyoo]

QUESTION: Do gravitational waves potentially have a spectral component to them that can be used to identify distance, mass and orbital information? Let's say LISA is powerful enough to regularly detect the hum of massive objects, what would those frequencies tell us? Is it even possible with LISA or would we need an interferometer that literally orbits outside of the solar system to get precise enough? As always, thanks for the excellent shows.

[@jonathanhensley6141]

I agree how you are saying we aren't going to run out of space and resources on earth. Our solar system has so much to explore before we begin to explore beyond our solar system.

[@extropian314]

25:02 A laser would totes provide a net thrust: Whether just shining the light out the back of the craft or "blowing the light fan at the sail" (assuming it's a reflective sail), it's a net release of energy in one direction. The latter case is just like a Shkadov thruster. (A reflected photon's momentum is being _reversed_ and so provides _twice_ the force of a merely "stopped" or "emitted" photon. -- minus any imperfections in the reflection).

[@sciencerscientifico310]

I could definitely see a time billions upon billions of years from now when stars are dying out and no new ones are forming that if we're still around we might create artificial stars mainly out of nostalgia.

[@wrongtimeweeder1076]

I've seen that video too. Showed it to friends. I love it. They hate it!

[@HPA97]

If the time of the universe reaches infinity before you cross the event horizon of a black hole, wouldn't this imply that the black hole would evaporate (Hawking radiation) before you could enter it?

[@eddiet.grijalva7291]

How would we know when infinity is reached? That's a bit of a pardox there.

[@johnchilds479]

Sadly, no. That effect is only experienced by observers. As far as the faller is concerned, the journey into the black hole is either uninterrupted, or ends in the accretion disk, from which the remains can be ejected at speeds close to that of light. In either case the poor guy gets spaghettified, not to mention dead.

[@TheWraithkrown]

I agree, that at this moment, it is not really feasible to colonize space. I think that not building towards that goal is foolish though. There are many things beyond our control that could make earth, and our solar system, uninhabitable sometime between now and the far future. There are individual humans with the ability to end human civilization if not humanity itself right now. I think that terraforming planets is not the way to go, if for no other reason that the inefficiencies involved. I think that building large, mobile, space habitats should be the goal. We are several hundred years from this goal at least with the current energy/time/funds humanity is investing in space research and technology, but I think it is achievable.

[@AndersWelander]

I love the notion of the great filter, although it is a scary theory.

[@SunShine-xc6dh]

The problem with the heat death of the universe is the universe supposedly started with almost uniform energy distribution and overtime has become less uniform. Take our solar systems even for example it started as mostly uniform cold dust cloud in to this complex energy producing system

[@EnneaIsInterested]

I think what makes sense about space colonization is encapsulated in cliodynamics. If Earth's sundry elites all experience competition from potential elites, and that is the ultimate cause of warfare, then settling space with rotating space habitats means we can have an interplanetary-Oort-Cloud-Nomadic shatterzone that KEEPS EXPANDING and can draw in peoples at superior numbers to even instances of relatively open migration, because the habitats will be spread out and encapsulated in a very different way from Earth's countries, so the killer feature is that you can have your culture, whether 'authentic' or synthetic, not threatened by a majority culture in the place you expand to, and so effectively space settlement becomes a siphon for discontent... So it's not just ideas, it's also long-term peace on Earth, we simply set up something dirt-cheap to facilitate emigration like launch loops, and then we implement various 'push' policies, the goal should be settling billions off-world, and in so doing make it possible for Earth's countries to have the stability needed to actually make things worthwhile.

[@guillep2k]

Fraiser, you've just gave the best argument against Dyson spheres/rings and also solved the Fermi Paradox: we can't see aliens because they've eaten their stars! Also, a possible explanation for the missing matter in the Universe. ;-)

[@frasercain]

Whoa, you're right. I might have also explained dark matter too. :-)

[@mattuk56]

Thanks for the video Patrick Moore.

[@frasercain]

Hah, I just need that monacle

[@Mordokrules]

Hi Fraser, when you were talking about Venus it got me thinking. Is there a 'geo'-stationary orbit you could put a satellite in around Venus? Given its day is so long would the satellite need to orbit at some extreme distance if it is even possible?

[@wrongtimeweeder1076]

Those geostationary orbits exist exist somewhere between all masses in our solar system (as far as I understand things). "extreme distance" Due to? Are you thinking gravity? Not sure it works like that.

[@wrongtimeweeder1076]

Good questions. Wish I had good answers. Upvoting your post, and replying twice to get some attention :D

[@Mordokrules]

@@wrongtimeweeder1076 mainly due to the time and velocity - on earth geostationary orbit is 35000 km while at the moon's distance (384k) a stable orbit is every 28 days. A Venusian stationary orbit would take 243 earth days to orbit Venus once, so I'd expect the distance required to maintain a stable orbit to be massive

[@wrongtimeweeder1076]

@@Mordokrules Hehe! Let's hear from some experts!! :D

[@idodekkers9165]

Hey Fraser regarding solar sails, sending them is "easy' but how do they stop when they get "there"?

[@frasercain]

Currently, there's no plans to have them stop. They just do a flyby and send back some photos.

[@sharonwarren1410]

What if the universe is a Klein Bottle? If that were so, the universe would continually fold back around turning and pressing back into itself creating a forever cycle of rebirth and renewal.

[@zapfanzapfan]

I really like the new thumbnails!

[@frasercain]

That's thanks to Anton, you'll see a lot of improvements from him across Universe Today.

[@theunknownunknowns256]

Could we build a endlessly long chain that is continually being built and added to, and then put the running end into a black hole? What would happen, could we use it wind up our grandfather clocks?

[@doncarlodivargas5497]

Why not simply wind up the clock, is that not easier? Anyhow, who use grandfather clocks when we have a mobile phone?

[@NullHand]

You could do something like that, but your problem would be finding a stable platform to stand on to spool out the chain. The least energy intensive way would be to do it from an orbit around the black hole. In this case you will essentially be building an orbital tether. A rather extreme one. You will need some seriously strong unobtainium for your relativistic steampunk clock winding chain. Stuff that could rock an Earth space elevator and yawn about it. Also, you will need a real clever way to arrange enough links of this to meet your steampunk majick dwarf chain foundry at the distal end of your tether with the correct orbital momentum to keep station.

[@Jenab7]

When the heat death of the universe is immanent, I'll just trot out into space and proclaim Let There Be Light. It'll fix things right up.

[@wrongtimeweeder1076]

And we'll forever be known as... SimSons 🤪

[@frasercain]

Wasn’t that an Isaac Asimov story?

[@Jenab7]

@@frasercain Yes. I was thinking about that story as I wrote the comment. _The Last Question_ is a short story published in a book called _Robot Dreams._

[@miinyoo]

Zero G metallurgy is definitely going to be a thing in the future. It's just too compelling to be able to alloy without density gradients due to gravity. Also, ferrous foams are possible but only in zero G. There's tons of stuff to experiment with on a scale that the ISS simply cannot do.

[@ivantuma7969]

24:57 You CAN put a laser on your spacecraft to power a solar sail ... IF ... the the laser was powerful enough, and the material of the sail could be microscopically ablated to produce plasma to push the sail - AKA "Laser Ablation Propulsion" ...

[@johnholleran]

If you stood on a sphere the diameter of the sun, how far away would you see the horizon? How does this compare to on Earth? P.S. plz don't try this. I just want a comprehendable comparison on the sizes

[@frasercain]

I use Wolfram Alpha for this kind of thing: www.wolframalpha.com/input?i=horizon+sun

[@olorin4317]

C'mon Fraser don't be so down, we just have to make an AI that loves humanity and life in general. Easy peasy.

[@MarcoRoepers]

Is a laser sail not very inefficient. How much of the power put into the laser will become thrust?

[@opcn18]

As I understand it light bends into a blackhole because the fabric of spacetime is stretched by the gravity. That topography is so extreme that nothing can get away from the blackhole before it gets bent back in. But that gravity is also supposed to be a wave in the fabric of spacetime (wasn't that what the laser interferometry showed us?) so why can gravity travel out from the blackholes when light can't?

[@PoleTooke]

Being under high pressure creates heat, right? So, find a big planet and send a long metal spear down to the center of it, and there will be a small temperature difference between the space outside/the surface and the inner planet under high pressure. Then, run a stirling engine off of that temperature difference. That should always work.

[@Trev0r98]

Fraser: Even if we take into account the 92 billion light years of this universe's event horizon , it seems probable that there are only about 3 or 4 "intelligent" alien species capable of making anything like a JWST. But we'll never know about it. Maybe many of them already did it, a few billion years ago. Regarding multiverses: likely. Likelihood of "wormhole" inter-multiverse communications? Figeddaboutit.

[@Slow_o.O]

Let's say flying tic-tacs are real and let's also assume they are man made. What kind of technology would have to be used to perform the mind boggling feats performed in the USN FLIR footages and what implications would that have on space and/or planetary exploration if that technology became available for use?

[@wrongtimeweeder1076]

Bloody technology older than my 'early' 1970s experience. Triangle. Red. Slow.

[@wrongtimeweeder1076]

If there is a lifeform just slightly more intelligent than we are, we're dumb.

[@starshipsn-9513]

Some sort of anti-gravity would probably be needed to allow them to fly with no visible propulsion system. If such a speculative propulsion system is possible, it would be absolutely game-changing. It would presumably be completely reactionless, making it vastly more efficient than all rocket technology, both theoretical and practical, that we know of. Assuming its power requirements wouldn't be impractically huge, following brachistochrone trajectories around the solar system would become trivial, greatly cutting travel times, especially if it could accelerate rapidly for long periods aswell. Maybe if such a drive could accelerate a ship efficiently for long enough, even relativistic interstellar travel could become possible.

[@wrongtimeweeder1076]

@@starshipsn-9513 Love it!

[@faizanrana2998]

Best show on utube.

[@jklappenbach]

What to do next? Focus on creating truly massive stations in orbit around the earth, the moon, and mars that can provide 1G reliably, and that we can live in with great numbers. We can't live in less than 1G, and so we'll need a place for us to rehab from time spent on off-world environments. Use starship to launch 100 inflatable segments. For less than the cost of a single SLS launch, we could afford to loft the equipment necessary to create a rotating toroid station over a kilometer in diameter. Need larger to afford slower rotation to provide 1G? It's only a few more reusable starship launches. Before we go anywhere, this is the next step. Once we have that, and prove that it's self-sustaining, we can set these up where ever they're needed: off the moon, off mars, in the belt for mining.

[@MyLittleMagneton]

Hi Fraser, I remember reading that the Russians had a proposed mission for early 2030 called "Mercury-P". Could you talk a little about that, and the challenges of landing on Mercury, please?

[@bmwolgas]

Just curious - when you say that the CMB as a source of potential energy will eventually "run out," does that mean it would literally reach a temperature of absolute zero? And if it can not reach absolute zero, do we ever reach true heat death?

[@wrongtimeweeder1076]

Heat death is the current fave. Though the Universe might just get ripped apart by the Black Hole we're falling into??

[@derivious2012]

so if he had the tech to dismantle stars we could significantly delay the heat death of our local area?

[@frasercain]

You could definitely delay the inevitable, but it won't be forever.

[@kennethhicks2113]

Yep, have fun and learn along the way : )

[@THIS---GUY]

What is the maximum amount of time an astronaut can spend in space? Is there any difference in total mission time below vs above the Van Allen radiation belt? (ISS expeditions vs Moon missions or Mars colony)

[@THIS---GUY]

P.S. Thanks so much for the content 🤯

[@frasercain]

The radiation beyond the Van Allen Belts is orders of magnitude more dangerous. Like, the Moon is 200 times more radiation than the surface of the Earth. But acute radiation sickness will come from solar storms, so it's all about your luck. The cosmic radiation will build up your DNA damage over time and eventually give you cancer.

[@THIS---GUY]

@@frasercain much appreciated! That is frightening. I've had the misfortune of learning the number of deaths due to heart disease among the Apollo lunar astronauts is almost five times greater than that in non-flight astronauts. I often wonder about the possibilities and limits of the human element of the Artemis missions and other deep space expeditions and how it changes with modern vs Apollo era tech and protection.

[@laurachapple6795]

"Ideally, we wanna destroy the Sun" is the most supervillany thing you have ever said. I'm gonna cross-stitch and frame it.

[@boredgrass]

a “reasonable solar flare”. I like that! ...Or...is it a “reasonable solar flair”? 🧐🌴🏖️😎🤗

[@chrissscottt]

I'm hoping the AI singularity will save us. Regarding black holes, if a spaceship were to steal energy from a black hole in the process of slingshot acceleration, where does that stolen energy come from if nothing can escape a black hole?

[@NullHand]

AIUI, the two ideas for stealing energy from a black hole require either the frame dragged spacetime outside the event horizon of a rotating black hole, or some other massive object orbiting a black hole. The first scenario your stolen energy comes from the "rotation" of the black hole, in the second it is a simple 3 body gravitational slingshot, and your energy comes from the orbital potential energy causing the body orbiting to move incrementally closer to the black hole. The second case is the same energy source that powers the gravitational waves that LIGO detects.

[@terlik3537]

Is there any way to modulate (AM, FM even Morse) of the Hawking radiation. If so there might be the way to send a information out of Black Hole.

[@frasercain]

The radiation isn't coming from inside the black hole, it's coming from the event horizon.

[@DaxLLM]

I have a basic question. How does one navigate a space ship if the ship is say 1,000 light years from earth? What is used to do that?

[@frasercain]

The best idea right now is to use pulsars. You can detect your location relative to known pulsars in the Milky Way and navigate that way. You could even do it within the Solar System.

[@DaxLLM]

@@frasercain Thanks!

[@curiousborg6441]

Hi Fraser. Is the "Starliner" ever going to be a thing? Will it fly? and how did Boeing become such a hot mess after decades of delivering on aerospace projects?

[@Christamaiztha]

15:26 i literally jumped up and ran to the kitchen to turn off my rice cooker! Then I realised I ate dinner 6 hrs ago..

[@frasercain]

Zojirushi!

[@Phil_AKA_ThundyUK]

You can totally put a laser on a ship and push it forward - point the laser backward.

[@thingsandstuffwithinmebrai5938]

*putting a fan on your sailboat would indeed work. :)

[@dustman96]

But can you cause disturbances in the hawking radiation to send information out of a black hole?

[@thingsandstuffwithinmebrai5938]

What do you mean by "disturbances"? The answer is most likely going to be no, but that's an interesting thought

[@bravo_01]

Hi Fraser, just found out about your show and loving it! My question is whether Israel has violated The Outer Space Treaty by sending Tardigrades to the Moon on board the Beresheet spacecraft? And if so, why did SpaceX allow them to launch using their rocket? Should their be consequences? Considering how NASA tries to sterilize all of its missions before going to Mars and so on to avoid contaminating the planets with Earth’s bacteria, and then we had that … Thanks - Your new listener, Greg

[@frasercain]

As long as they’re not armed with nuclear weapons, it’s not a violation of the Outerspace Treaty. But there is a new Planetary Protection committee that’s making recommendations about this kind of thing, and they’re not super happy.

[@bravo_01]

@@frasercain Much appreciated for fast reply! Thank you

[@chadr2604]

I reckon the only economical fusion plant would be inertia confinement and use a fiber laser and laser amplifiers like a metal cutting fiber laser on steroids. We have a fiber laser where I work it uses a laser diode that is a few watts it goes through several stages of amplification then it goes to the actual nozzle.

[@blitzmotorscooters1635]

thanks

[@frasercain]

You’re welcome

[@phibetakafka]

Will we run out of cosmic microwave background before the expansion of the universe redshifts them to undetectable levels? If the universe is finite, could there be a point where the last CMB photons from the exact edge of the universe reach us? And does the CMB change over time, e.g. would hot/cold spots change over time as hot areas further away from the current cold ones come into our cosmological view?

[@ahaveland]

Cheerful episode today!

[@frasercain]

Yeah, it got pretty dark.

[@OzHafakot]

Hi Fraser, love your show. What if, instead of ending the space station program in a decade like advertised, they will give it a strong boost and send it to the Orbit of Mars? Astronauts could still be inside orbiting Mars and even sending manned mission to the surface. What do you think?

[@phoule76]

Apparently it's not hardy enough to withstand cosmic rays outside of the protection of Low Earth Orbit. Plus, the hardware is aging, so it would be easier to design and launch a new one.

[@sharonwarren1410]

I think we would need a better space station made specifically for orbiting and studying Mars.

[@whatelseison8970]

He Fraser, I've had a question that's been bugging me for like a year now and this "Earandel" (sp?) star observation has brought it back to mind: Why is it assumed that none of the first stars - the so called Population 3 stars, could have survived to the present day? I get that giant Oh-sh*t type stars would have been the norm and they'd have lived fast and died young but I find it impossible to believe that there were NO red dwarfs formed from that primordial gas. Like how is it that only 2 generations later and the demographics of star populations have fully shifted towards small stars being the norm? None of this is deterministic. It would follow a statistical distribution, albeit a dynamically weighted one. So yeah, I'm pretty sure the conventional wisdom is just obviously wrong, and I don't say that lightly. The question is why.

[@wrongtimeweeder1076]

Statistical evidence. The 'observable' Universe (which probably doesn't cover very much). I don't disagree with you. The best answer is, 'we're still infants here.'

[@absalomdraconis]

I believe that part of the reason is the plentitude of gas, and sparsity of competition. The initial population of stars would have formed in essentially a _universal_ nebula, and one with very few causes of focal points, so there should also have been very _few_ population stars, and just about all of them (if not literally all of them) would have _started_ as giant stars. It's been suggested that some may have been so massive that they _skipped_ the star phase and went straight to a black hole.

[@parkershaw8529]

Fusion at best can use 1% of the mass, advanced civilization might use a blackhole to access energy.

[@wrongtimeweeder1076]

@7:21 I hear ya... but I also know that you know 'going to Mars' is not just about 'living' somewhere else... 😀

[@frasercain]

Sure, if we’re exploring Mars, it makes sense to take all that risk and expense. But if you just want a cool place to live we’re going to need more tech.

[@user-tg7kv9df4c]

Competition is always important.

[@EASYTIGER10]

I imagine a big cloud of Hydrogen near Earth would soon be dispersed by the solar wind. If you put an Earth sized cloud at Earth's L2 point (where James Webb is) so it was protected, would it be safe? Or would the solar wind or other things eventually break it up?

[@colinhouseworth9027]

Short answer, no. Long answer, the L2 Lagrange point (along with L1 and L3) is meta unstable so only objects with their own thrusters like JWST could stay there. L4 and L5 are meta stable but only for negligible amounts of mass. The surface gravity of the planets themselves is the most stable place to hold hydrogen but the inner planets are unable to hold on to this lightweight element due to solar wind. Even Jupiter and Saturn are constantly losing hydrogen to the solar wind.

[@1redneckfish]

Does a black hole have an atmosphere of any kind, whether it be gas, liquid, or other type of matter, such as exotic plasma,etc etc?

[@pwatsky]

You asked for it...Assuming Einstein's General Theory of Relativity is correct ( and I am not saying its wrong), that means any large body deforms Space/Time (bowling ball picture). That "creates" gravity, no force, no graviton necessary. How do we then say, there should be a quantum theory of gravity with gravitons present?

[@Warrenoutruckin]

Could u offset the “photonics thrust” for a light sail by pointing the laser towards the bavk and using mirrors set at minut angles so that it eventually creates a semi circle allowing the beam to now impact the sail pushing forward? So now not only will I have the push on the sail but also the photonic thrust working in tandem

[@syntra2388]

About the only way you could get more thrust than pointing the laser straight backwards would be to point your laser at the edge of a black hole in a binary and have it loop around it and hit your mirrors. It can't be a black hole you're towing either

[@mishkosimonovski23]

Creating a Star is such unneficient use of hydrogen as if you make a fire in your backyard in order to warm your living room....instead of central heating inside the house. Most efficient will be collecting as much resources as possible (dismantling stars before they evaporate) and keeping the hydrogen for Antimatter annihilation, which is most efficient.

[@robrobrex]

Hi Fraser! I’ve got a question, anything new from Juno?

[@frasercain]

We’ve been seeing some cool new images from Ganymede

[@robrobrex]

@@frasercain thanks! I'm gonna check them out

[@ocoro174]

can never have enough fraser

[@chadr2604]

When the carbon detonates in a white dwarf it must have a real high fusion cross section it unbinds the whole star. The pressure must make a difference.

[@joaodecarvalho7012]

A red dwarf looks like a good generator.

[@madderhat5852]

Please don't touch Jupiter. It leaves fingerprints and 'somebody' ends up having to polish it again😣

[@frasercain]

Yeah, hard to buff it out

[@captainmaay]

Question : why are there gold nuggets on earth ? If these atoms have been ejected from supernovas, along with tons of other type of atoms, why do they end up together as nuggets (or asteroids even) and not a messy mixture of everything clumped together ? Isn’t that against entropy ?

[@jmacd8817]

Simple answer; gravity. Once there is enough gravity to condense gas and dust into a star and planetary nebula/protoplanets, denser materials start to fall towards the gravitational center point. On earth , specifically, at the earth’s early existence, it was a molten ball of stuff. Because of the different densities of different materials, denser materials fall to the center of the earth faster than other things. If the earth stayed hot enough, for long enough, without any disturbances, the very center of the earth core would be gold, lead, tungsten, iron, nickel ( and any other dense metals) alloy, with lighter materials occluding in layers. This was part of “differentiation “. Earth cooled fast enough, and there was enough disturbances/mixing to keep a moderate amount of dense materials on the earths surface and crust. Gold, and a few other metals are in reactive enough 5at they don’t react much and can stay in their elemental form (ie, pure gold, and not gold oxide, like iron oxide/rust). Some materials, gold included, likes to stick to itself, so during the slow cooling, lumps of like materials came together and stuck. As for entropy, the earth is not a closed system, so the rules for entropy don’t really apply. This is further confounded fact that the various separations, etc, occurred when the earth was still quite hot and in a very complicated state, which makes simple declarations of what entropy would allow or not allow becomes VERY difficult.

[@trbrobibond]

Hi Fraser, the IPCC demands immediate actions to limit the global warming to 1.5°C. Sending a satellite in form of a giant umbrella to the L1 orbit point to block/dim the light from the sun hitting the Earth could be a solution ?

[@chadr2604]

Generally I try to punch everything we have a tool for and use the laser instead of nibbling then part it out with a .250x4.000" tool

[@beautyqueeninminneso]

Can a CME be triggered/caused intentionally?

[@PhysicsPolice]

27:30 This is a sort of special pleading. Yes, all species that’s have ever loved have gone extinct… except the ones who didn’t. And that includes everything alive today. I’m the latest in an unbroken line of survivors dating back a billion years. You’re gonna bet against those odds? Ok.

[@frasercain]

It's always mind-blowing to think that every single one of our ancestors was successful at finding a mate. We come from a line of winners.

[@blueredbrick]

I'm so happy to have two daughter. It kinda feels to be immortal.

[@ultramovier]

Is it possible to have a negative mass higgs boson?

[@TheMasterashton]

Hey Fraser my question is: if someone Is orbiting Jupiter then they see a rock flying past at 10% the speed of light what colour would his shoes be

[@frasercain]

I’m going to guess white since they’ll be an astronaut in a spacesuit

[@LIMITLESS_RC]

Do you think we are the first intelligent species that has survived several great filters? I think we are just the first to survive that the galaxy is vibrant with life such as bacteria/viruses etc.

[@clive3490]

More questions in a second but first I have to go and sort out my rice cooker..

[@frasercain]

All hail my Zojirushi rice cooker.

[@Phil_AKA_ThundyUK]

if Mars once had a similar biosphere to Earth (as is a possibility) could it contain fossil fuels? And is there a realistic way of finding them without setting up a huge drilling operation?

[@matttyree1002]

if fusion produces more energy than fission, could we replenish our hydrogen supply by doing fission on the helium byproduct, powered by the energy of fusion?

[@WilhelmDrake]

With a population of ~7 billion, we currently produce enough food to feed 11 billion people.

[@frasercain]

Yeah, we should be able to feed everyone. And our population is going to be decreasing in the next few decades naturally.

[@Nefertiti0403]

Okay. I’ll ask a question. Will we ever turn into an alien life form? Or can we or will we grow wings and fly??

[@wrongtimeweeder1076]

Possibly both 🤣

[@ButterHaus420]

Confirmed: Fraser can observe your dreams and also the dreams of anything in the Universe

[@wrongtimeweeder1076]

And the smarty-pants can upload a pre-recorded video before the video is recorded! Physics is wrong! 🤫

[@julians7268]

I was wondering when he'd open his eyes...

[@aelolul]

?

[@DamianReloaded]

8:00 Earth is the best place in the universe, until it isn't anymore. And then it will be just as hard to live on Earth (maybe even worse) than anywhere else in the solar system. It's like saying my family house right next to this volcano is the best place on Earth I could possibly live in, so, I will not move, nor think of any alternative or plan B. Scientists say this volcano is very likely to never go off so I'm safe.

[@frasercain]

Even the worst possible version of the Earth is infinitely more habitable than any other part of the Solar System.

[@DamianReloaded]

@@frasercain The worst possible version of Earth is Venus.

[@david-2]

Let us wishfully think! Indeed - best advice anyone could give!! Have smart babies, accept your own mortality, and let our children shape the future :)

[@frasercain]

Sounds great!

[@WatfordCaroline]

Hi Fraser ❓What weather systems are there on Mars and are they dangerous should humans ever try to terraform it? Thanks, Caroline

[@mizzshortie907]

Dust storms 🤷🏻‍♀️

[@rJaune]

Does Earth have more interesting and varied weather than other planets in the Solar System, or do we just notice more things because we are directly affected by it?

[@whatelseison8970]

@Brian Sparks No offense to Fraser but I feel like he sort of lost the plot in his off-the-cuff answer to your question. On planets without a solid crust the surface is defined to be the depth at which the atmospheric pressure is 1 bar. Also, the core of Jupiter is thought to be about 5000 K, not 80 000 K. Saturn is thought to be as much as 11000 K, but even the hottest stars only have surface temperatures of about 60 000 K. Planets are hot inside but not that hot.

[@frasercain]

The core of Earth is 5000K, same as the surface of the Sun. Jupiter is way hotter. I just double checked and it’s 20000 K. I’ll make a mental note of that.

[@whatelseison8970]

@@frasercain Oh. Wowie you're right! That's based on new data from Juno (2020). That's very interesting. I'll have to make a note of that as well and remember to brush up on the rest of the latest deets from Juno. I love Jupiter. Gas giants are so bizarre. As fascinating as they are terrifying. I appreciate the response though. Always nice to see you in the comments. Cheers!

[@chadr2604]

Don't stars rely on pressure I thought the fusion cross section is crap at the temperatures inside a star.

[@Saalome84Blue]

....maybe one day in the distant future, someone will try to turn Jupiter into a star ;-)

[@chglasier]

how many generation of stars are there. If our sun is a third generation, how would it be different from a fourth generation and so on.

[@Gamefreak924]

Hi Fraser, I'm late, but how was the rice? :D

[@frasercain]

Zojurushi!

[@CeanStrauss]

I don't agree that we've explored every nook and cranny of earth. There's always a chance for underground lizard people. 😁👍

[@dropshot1967]

Maybe I am being an idealist, but I feel we should keep on chipping away at the difficulties of living in space. If we are able to mine asteroids for use in space (transport back to earth is most likely not economical) That would enable us to make O Neil cylinders and other large colony sized space habitats. The bulk of humanity will probably be living on earth for at least 500 - 1000 years, maybe longer. But having the possibility to leave earth and live in space will attract the pioneers/adventurers and just the flat out poor, that want a chance to get ahead and are willing to take a chance. That was the main reason for most of the early American pioneers anyways. Surviving AI, or an idiot in a garage or any number of other catastrofies, is all the more reason to have people being able to live self-sufficiently off-planet. just to make sure no single thing can wipe out all of humanity.

[@frasercain]

I think your timeline makes sense. I 100% agree.

[@gitmoholliday5764]

it is an idea stolen from some science fiction book but wouldn't it be easier / practical to create "nano" fusion ? it for sure would require less energy to contain a little bit of plasma and if that way fusion will become possible we still have enough energy to maybe power an vehicle or airplane. 🤔

[@absalomdraconis]

It currently looks like going _bigger_ is what gets better results, not going smaller.

[@mattbrookbank]

If in the far future, humans built a sky city on Venus the size of let's say Los Angeles on massive stilts over the highest mountain on Venus... over time how would thr area under the city change when no sunlight hit it?

[@CarFreeSegnitz]

27:10 “Will we survive?” What a shocking level of a lack of faith or plain ignorance. Here we are on the backs of millennia of our problem-solving ancestors. They were confronted by millions of existential threats and overcame them. We’re knocking away existential threats at an even greater clip. I can’t name all the big problems we face today. But I can say that historically our ancestors faced big problems too and obviously solved them. They stuck it to the guy or gal who couldn’t imagine any other caves to live in. They stuck it to the guy who couldn’t imagine a pattern of migratory animals. Agriculture. Villages to towns to cities to agglomerations. Malthus sounded logical but he was wrong. War seemed endless in pre-1900 Europe… then the European Union. We were all going to die in a nuclear war… then MAD. How do we solve global climate change? How do we ensure no one biohacks a super disease? How do we prevent a malignant super AI? How do we survive our sun going red giant? I don’t know. But as we’re quite a bit more clever than our ancestors from 100,000 years ago it’s certain our descendants will be quite a bit more clever than us.

[@frasercain]

I'm hopeful, I just don't think we can take it for granted. We're also running up against existential threats our ancestors never faced. But I think we'll navigate them.

[@Gocast2]

0:12 I dreamt you a question 3 weeks ago and you still haven't answered it 😭

[@scottdorfler2551]

I have an idea 💡 Let's ban all astronomers from naming anything. For example do you think it could be anymore confusing than naming the first stars 🌟 population 3 stars. They got lucky with population 2/generation 2, but population 1/ generation 3, come on 😩🤡🤓. Star designation is a train wreck too! A bunch of random letters O M F G!!! see what I did there. And OMFG!!! The EXTREMELY LARGE TELESCOPE!?!?!? Is that really the best they could come up with. That's like Ritchie Cunningham naming his band the band.

[@jamalrobinson8321]

Kardashev scale needs decimal points

[@frasercain]

I've heard people estimate that we're Type 0.7