New Voyagers, Disc Golf on Mars, Limits of Future Telescopes | Q&A 268

[@PyroRob69]

Can’t really choose any specific story but they are all good and great food for thought. As far as Voyager is concerned, we need to send a couple out that this time has the primary goal of getting to interstellar space with the highest velocity possible. Put all the instruments on it, and do the orbital boosts around the sun and Jupiter. If you want to explore on the way, fine, but realize the primary mission is interstellar space. Since we know RTGs will work decently, send it with several RTGs that are more than 150 W. Send them out with 500 W each. This deals with the normal decay. Then they can run all of their instruments all the time and not have to worry about not having power to keep everything warm.

[@frgv4060]

Voyager 3? I thought that was called New Horizons. The next “voyager planetary alignment” is still more than a hundred years from now. I think it is not really needed. I mean it is cheaper return wise to use more propulsion (or not) to get to each destination than to do a long mission by “dancing the planets” on flybys then going interstellar using resources for decades with little science return that we don’t already know. Just my opinion.

[@PyroRob69]

@@frgv4060 No one said anything about a planetary alignment. This needs to be about getting to the Oort Cloud and fatter out. If we happen to do some slingshot’s around planets for increased velocity, that’s fine but don’t make the planetary exploration the focus of the mission.

[@frgv4060]

@@PyroRob69 The planetary alignment was the whole premise of the voyagers to easily visit the outer planets with consecutive gravity assists, then escape the sun operating as long as possible. Ok, New Horizons does not fit the bill as I read it is not intended to operate beyond the Kuiper belt. My bad.

[@paulmichaelfreedman8334]

@@PyroRob69 If we send a probe out to the Oort cloud, even at the highest possible velocity imparted by chemical rockets, AND nuclear rockets, it would still take over 10,000 years to reach the inner frontier of the cloud. And even then, objects are extremely far apart, it would likely encounter absolutely nothing on its way through and it would take another 20,000 years to get to the outer frontier. The Oort cloud has a diameter of about 1 whole light year. The kuiper belt is what is interesting, and measuring interstellar space which is present well within the Oort cloud, even within the Kuiper Belt.

[@PyroRob69]

@@paulmichaelfreedman8334 If we started 50 years ago, we would be 50 years closer, wouldn’t we. In all honesty, if we really want to explore, we need to find a faster way to travel. Solar sails aren’t the answer. A new technology is required.

[@TheLadyWrites]

Question: How do the recent solar flare impacts rank against the Carrington event? Are we ready for or have we already experienced an event equal to or greater than a Carrington event?

[@arnoroebersen3670]

Question: if you feed a neutron star one atom at a time to turn into a black hole, would it slowly fade out or would it instantly turn dark like a light switch?

[@Kanitoxx]

I feel that we can ask this but with throwing earths at a time and still getting an "it depends" because we don't really know the exact Tolman-Oppenheimer-Volkoff limit... and that only works on cold, non rotating neutron stars, real ones are very very hot and rotating really fast, so the mass thrown to the neutron star can speed it up or down depending how you throw the mass, how fast you are throwing it and so on. You can get a supernova first or a sudden collapse... we don't know.

[@HansMilling]

A follow up question, what if it’s just more heavy elements from the start. Like rocky planets put together, more and more at a time. That would never ignite into a star.

[@paulmichaelfreedman8334]

In ideal circumstances....fade out. When a neutron star gets real close to the limit, it's gravitational field will redshift light into the extreme. So it would get redder and redder and dimmer and dimmer until even Gamma and X-rays are stretched to long radio. The moment the wavelength of all emissions fly off to infinity, is the moment it turns into a black hole.

[@AlaskanBallistics]

Love how they're showing regular Frisbee instead of disc golf

[@Juttutin]

41:52 I was talking with my bestie the other day about the emotions of discovering one is wrong about some belief. Like you I almost always enjoy this novelty and greater understanding of 'reality'. And then you said "I am an agent of chaos in my personal life, just ask the people around me" and I guffawed so hard, because yes.

[@richardreumerman5449]

Exactly right, the emotional rollercoaster I go through when someone points out a mistaken belief and how I could improve it is hard to describe. If you accept and embrace the shake up it's great thigh.

[@kellyrobinson1780]

42:07 SO: Are you The Joker, or an enemy of Maxwell Smart, Agent 86 of CONTROL?

[@robertoliver7985]

Disc golf on titan! Super stable 14 speed disc would fly amazing.

[@Quark_433]

Those Tilts that everyone bought on a whim may be throwable for once..

[@clausqp]

hey, so good to hear you angle on things in and around science/astonomy ! keep up the good work. Thank you🙏

[@pi1392]

This QA was soo good. I'm gonna watch it Many more times before the next episode drops ❤❤❤

[@arob9981]

Hey there Fraser. Fellow BC resident here. In the Kootenays. The "another Voyager" question reminded me of this question. I have heard there was talk about launching a probe toward Sedna because it is near the closest point to the sun. They have said if they can launch soon, they could get to Sedna in 25 years or so. Of course with its 11,000 year orbit, this will be humanity's only chance to go to Sedna. So my question is HAVE YOU HEARD ANYTHING ABOUT THIS MISSION AND IF THERE A PLANNED MISSION TO SEDNA? I really hope they do. It should not be problem technology wise. The Voyagers have been alive for over 40 years and they used up a lot of power at the planets. This probe could basically be off for years, maybe on sparingly, so it could save most of its nuclear power until it got out to Sedna and maybe even use some of that power to slow down so its not a much too fast fly by like Pluto was. I would think because its so dark out there that they would want to spend more time close to Sedna to get the most imaging done and a little better visible light shots. Anyway thanks for the videos and I hope you can answer this one. ;) By the way. Feel free to edit this question any way you need, to make it better without taking the point of the question away lol.

[@frasercain]

You probably heard about that mission concept from me. :-). No, there's no additional progress on actually making it happen. arxiv.org/abs/2112.13017

[@arob9981]

@@frasercain Thanks for the link Fraser. God info there. I wonder if they will suggest the mission and make it happen?

[@Stewie801]

Hadante for sure

[@Insanati]

Dakara. And in regards to that topic, if the universe is infinite, then the chance of the exact "fundamental particles" coming together in the same way to recreate "you" is a certainty, it just might be an unimaginably long period of time before it happens again. It will be "you" and "your body" exactly as it is now made of the same materials. The odds of such things are ridiculously low, but multiply any odds by infinity and you get a certainty. I think in terms of your perception, this would probably be like living forever, you would cease to exist for trillions of trillions of years, but then you would "wake up" in a new you without your previous memories and live another life.

[@EdwardHinton-qs4ry]

That's the answer I wanted from Frazer. We may die but we won't experience the near infinite amount of time until the next universe comes around and suddenly we are reborn again.

[@gerardwalker2159]

I wonder how many times it has happened. Once? 4 times? An infinite amount of times already? Also how mamy times was it the exact same atoms. Not just the same composition but the exact same particles?!?! I think thats what needs to happen to becomena god. Infinite things hurt my brain sheesh.

[@jimrichards7014]

If this happens an infinite times, there is a finite chance that everything would happen exactly the same.

[@laurachapple6795]

Cartego, just for the phrase 'black holes are only made of black hole'.

[@808bAler]

Tremendous episode, Sir, what an outpouring of knowledge.

[@SteveNoettl]

your last episode (new voyagers) was the best explanation of the universe that I’ve ever heard in my life, you would be the guy I would want on the big space ship flying across the galaxies - you’re able to explain the universe in the same down to earthiness as one would give directions to finding a good sushi place, there are so many admired scientist and physicists that just can’t convey these subjects without drifting into outer space- you just have that science je ne sais quoi - so many good and fascinating subjects; safe travels - cheers

[@frasercain]

Aww, thanks. I'm glad that helped explain things.

[@uncleeric3317]

Question: what is the size and shape of Lagrange points? Are they flat, oval, spherical?

[@Kadath_Gaming]

Is it possible that the large scale Voids in the universe were the original locations for the Pop 3 stars,the Voids having expanded with the expansion of the universe?

[@takanara7]

No. It's actually thought that globular clusters are the 'remains' of pop-3 stars

[@bjornfeuerbacher5514]

The Pop 3 stars were located in galaxies, not in voids. They needed lots of mass to form. And even after they exploded, that mass still was there. So why should now there be a void in those places?!?

[@Kadath_Gaming]

@@bjornfeuerbacher5514 there ARE galaxies in the Voids. The original pop 3 stars would have formed rapidly from collapsing gas and grew very rapidly before going supernovae and propagating shock waves in the early more dense universe. My thought was that as Space itself expands, the boundaries of the various pop 3 supernovae shockwaves would compress the gas into filamentary structures of the cosmic web, leaving the mass at the centre isolated in a Void. So yes the original mass of the pop 3 star would still be in the Voids.

[@bjornfeuerbacher5514]

@@Kadath_Gaming Yes, there are some very few galaxies in the voids. So what?!? Pop III stars were located in _all_ galaxies, not just in the very few fraction of them that are now in the voids. "the boundaries of the various pop 3 supernovae shockwaves would compress the gas into filamentary structures of the cosmic web" Sounds nice at first glance, but does not work if one actually does do the math.

[@AlaskanBallistics]

Have a great trip!

[@ekaa.3189]

Question Answer: Sep 23 show, lightning off planet. Lightning doesn't need a ground. In only needs areas of a gas cloud that are at different electrical potentials, and the gas cloud needs to be dense enough to support electrons jumping from molecule to molecule to initiate the lightening strike. One should get them in a gas cloud that is condensing into stars and planets. Look up Sprites which are more of a fluorescent tube like effect. Wikipedia has a good page on "Upper-atmospheric lightning". I'd say engage an astrophysicist with the question of extra planetary lightning. I last studied astrophysics over 4 decades ago and never pursued it as a career.

[@stile8686]

Hadante. Great answer.

[@garethsmith3036]

We got to get to voyager six in time so it can turn into v-ger

[@robthomas3664]

@@garethsmith3036 aren't we already about 30-ish years past that deadline? If I recall, it was supposed to launch in the 1990s...

[@jackdowling4606]

What might a Voyager 3 probe, in 2148 (next Grand Tour opportunity) look like?

[@therealpbristow]

Hoo boy, trying to predict the results of a century's worth of astronomical & technological advancement is no small ask! =:oo But since you used the word "might", well... it *might* look like a Jammy Dodger. Or a Dachshund... Yeah, probably one of those two. =;o]

[@kamilZ2]

23:50 Using thrusters near the Sun is more effective - Oberth effect. Fast spaceship gains more kinetic energy from Delta V and potential energy of fuel left near the Sun is smaller.

[@sierravortec2494]

Fraser I want a break down on what it would be like if we could play hockey on each world in the solar system!

[@jimmirow]

Need more information on your paramaters. ie. Are you considering having the game played on ice or gaseous giants? Your inquiry presents a Bunch of variables!

[@istvansipos9940]

is that the most Canadian question ever?

[@jimmirow]

@@istvansipos9940 yes! And I'm here now remembering the 1980 Olympics😲. I'm nestled here in Indiana but still find myself rooting the human race rather than a country. ie. Mike Weir did a wonderful job this weekend and I've always been a big fan.

[@greggweber9967]

24:30 It's not just speed. It's also direction. You probably don't want to go nowhere fast.

[@mikegLXIVMM]

Interesting video, thanks for posting!

[@dannybrown5744]

"I see everything " I love it

[@mateobarnstone1591]

Since you invited questions - here's one I've wondered. As I understand it, the cosmic distance ladder is a series of techniques that are used to calculate distance between deep space objects and that the first and most fundamental rung on the ladder is the use of parallax between distant telescopes - or in the neat trick in the case of stellar parallax, using a telescope measuring objects form opposite ends of its orbit. The limit here is, we're 1 AU from the sun and so on earth (or in orbit around earth) we're limited to 2 AUs of distances between observations, thus limiting the utility of this method to relatively close objects within 300 light years or so. But would it be possible to launch a telescope and park it in Jupiter's orbit. Jupiter is 5 AUs from sun and you could get a 10 AU difference between measurements. Would this allow us to measure with much greater accuracy objects far more distant and improve the entire cosmic distance ladder? Jupiter's orbit around the sun is only 12 years - so you would only need 6 years between measurements, why I suggest Jupiter instead of a more distant planets like Saturn, Uranus, or Neptune where we'd need to wait decades.

[@richiebricker]

I think you explained the current model of the universe perfectly. Ive done a lot of reading on the begining of the universe, mostly Carl Sagans books and I dont remember reading about this dark age or 2nd Opaque-ism. Do ya have advise for things to read about this? I think it gets skipped over cause its not too exiting "nothin new too see here, in fact ya cant see it" kinda thing. I cant wrap my brain about it case I dont know about it

[@leightapex]

Fraser. I just wanna say. You’re darn good. Love listening to every question show/universe today episode. Just sayin’

[@MelindaGreen]

I never heard the risk difference between asteroids and comets explained. New existential dread unlocked.

[@AnonymousFreakYT]

Well, the bit on "more Voyagers" had me go look up the latest on the Voyagers. Two instruments that are still active on both still have living original primary investigators: The Low Energy Charged Particle Instrument has as its primary investigator from day one Stamatios Krimigis The Plasma Wave Subsystem has as its primary investigator from day one William Kurth. I'd love to see an interview with the two of them - scientists who have been working on the same project (among others, it's not like the Voyagers are a full-time job) for over 45 years.

[@philipmumford7871]

Hi Fraser love the show! Q. Your piece on why you go along with the big bang made me think. When was the most recent time someone came up with something that made everyone go "whoa we were all wrong!" in a big sense. Such as quantum theory or Hubble noticing the expansion of the universe. Was there anything more recent that made waves (literally or figuratively!) ....

[@Kanitoxx]

It's mind boggling to think that the observable universe was in a space the size of a volleyball... and yet, we can think that there was more outside of the bubble we can observe. That also at one point the universe had de conditions equal to the inside of a star but in all its extention. Just trying to imagine the conditions of the gas formed as soon as the universe was cold enough to support chemistry, the density needed to start collapsing into stars and how hot it got in a few million years due to so many giant star spawning all over the place reionizing the left over gas. I hope we can reach the levels of simulations where we can take into account magnetic fields and the most particles we can into the models, as time has proven again and again, more detailed models have shown more things that we didn't even consider before.

[@georgegyulatyan3263]

Ardena Question: Lately (well at least the past 10-15 years) there has been more and more conversation and hypothesis, and some theoretical work in regards to emergence. You have emergent gravity championed by scientists such as Erik Verlinde and then even towards the far far end, the concept of emergence of spacetime itself with physicists such as Nima Arkani-Hamed… The question is, do you think once we have figured out the next lower level “stuff” that spacetime emerges from, we’d then eventually develop a technology to allow us to be everywhere all at once? But, don’t think of as gods, but more like Q 😊

[@Chessendgames4235]

Hi Fraser My question: I’ve been observing & imaging aurora in the atmosphere. Other planets also have aurora particularly Jupiter and Saturn. If these planets were inclined at the right angle, what equipment would it take to image them? Could an amateur setup with, say, a 200mm aperture scope & planetary camera achieve this with the right filters?

[@legoyodascream]

Was there a canceled project to make a lander for Pluto that was going to take like 100 years to land? I just remember my professor complaining about the cancellation it like 10 years ago. I can't seem to find anything about it online, though.

[@al3xa723]

I've never heard of this before but interesting idea

[@ElyonDominus]

Could be that it wasn't "cancelled" per se but was instead merely not selected to be developed in the first place. I haven't heard of this mission but I'd love a dual lander mission with an orbiter between Charon and Pluto and landers on each. I think we really ought to formally recognize the Pluto and Charon system as a binary dwarf planet system.

[@takanara7]

The problem with that is that you'd probably have more advanced tech developed in the next 100 years so like 90 years from now we could probably get a lander on pluto using nuclear powered ion drives or something.

[@angelainamarie9656]

That would be mad.

[@angelainamarie9656]

​@@takanara7the other problem is that you couldn't depend on the government or even the nation to still exist. It would be very difficult to ensure any follow through.

[@Weezwr]

Haha loved the change from voyager 2.0 (voyager 2 lol) to voyager 3

[@StefOne-nw9un]

my vote is on chulak ^^

[@StefOne-nw9un]

ok, edora is also a pretty great one... i'd love to see a mission destined for the interstallar space while observing the oort cloud on the way... guess i have to wait a bit ;-)

[@buddy.boyo88]

Q : are you familiar with Halton Arp's steady state cosmology ? and why do you think he's wrong ? thank you if you address !

[@lethargogpeterson4083]

To expand on how hard it would be to see stuff in our own Oort cloud, consider the brightness scaling. Most comets are small, so Oort cloud objects probably are small to start with. Since they are cold, radiation directly emitted by an Oort cloud object would be very long wavelength (far infrared?), then expand outward in a sphere as that radiation travels out, so the brightness drops off as the distance squared. Pluto is less than 50 AUs (Astronomical Units, earth to sun distances) away. An Oort cloud object 50,000 AU away is 1000 times farther so a million times dimmer...if it were as big as Pluto, and they probably aren't. But it gets worse. The distance squared law is for (very cool) heat radiation they are emitting directly. We first detected Pluto in visible light, reflected from the Sun. The Sun's light gets dimmer with the same distance squared relationship, so 1000 times farther than Pluto the sun is a million times dimmer than at Pluto, then that light gets reflected scattered in many directions (not a mirror), so that million times dimmer light then goes through another distance squared brightness relationship coming back. So, for reflected light, it is a distance to the fourth relationship. A 50,000 AU Oort cloud object about 1,000 times farther than Pluto will be a trillion times dimmer in reflected light (and be smaller than pluto, and be moving slowly in such a distant orbit that you might need to get a spectrum of the light colors to know it's not a very distant, faint star.) Given the distance relationships, I find it impressive that we have found so many Kuiper Belt objects even!

[@mikegLXIVMM]

7:02 Gyroscopically stabilized rotating airfoil.

[@smkolins]

another question… Like the question of how we have a matter universe and not one that was perfectly balanced with matter and antimatter… but with the opposite emphasis… Why are the number of electrons and protons in the universe equal? Or put another way why is there no net charge in the universe? I thought to this at the q/a of the cooling universe forming atoms after the first period of ionization.

[@ioresult]

Asuria: just dig a tunnel at the base of Kilimanjaro and beneath the peak, make a underground VAB, then lift the launch platform up to the summit on a giant elevator. Easy.

[@evilmage42]

Hi Fraser, is there a correlation between the size or amount of planets to the size of the star?

[@tarumph]

I have a question for you. Does the heliosphere, where the solar wind interacts with the galaxy wind (not sure that's the right term), impart a drag on the sun? Is there any thrust from this interaction? If so, how much? Tim Rumph

[@igorscot4971]

If you placed a satellite at Lagrange point L4 or L5, theoretically, you could communicate with a telescope at Lagrange point L3. Would it be better to measure the distances to stars than what we do now?

[@ezpzenterprisesllctennesse4443]

Frazier do you think some of the Keyhole Satellites that are in storage could be repurposed for deep space exploration?

[@nochance3914]

I have two question. 1)Is Big Bang theory incomplete? Once on record you said to someone last year that 'you are centre of universe as everything is moving away from you.' Now,lets assume I am centre of Universe,then why I have to look for cosmic microwave background radiation by telescope? Won't that cosmic microwave background radiation be on me or you? 2)By simple physics,centre should have highest level damage and proof of radiation in big bang. If that cosmic backgound radiation is at outer edges, don't that mean universe is expanding from centre and not from outside edges?

[@bjornfeuerbacher5514]

"Is Big Bang theory incomplete?" Yes. E. g. we still don't know what dark matter and dark energy are. We still don't know if inflation even happened. etc. "Won't that cosmic microwave background radiation be on me or you?" Yes, it is. But it is quite faint, so you need a telescope in order to collect the few photons that are there. It's the same with faint stars: there light also is on you and me, but nevertheless, you can't see it, because it is too faint. You need a telescope for collecting the light. "By simple physics,centre should have highest level damage and proof of radiation in big bang." The Big Bang was not an explosion starting at one single point. "If that cosmic backgound radiation is at outer edges" It isn't. It is everywhere in the universe.

[@prashanthraj3416]

Hey Fraser! Huge fan by the way. How many stars escape milky way or any other Galaxy on average?

[@Apobothra]

Personal question: Are you more into the universe being a simulation or the laws of our 3D-universe being imprinted on the 2D outer boundary? They can both be wrong or even both be true of course, but which of these hypotheses interests you more? Thanks for the great content!

[@frasercain]

I don't have a preference for this, or really any scientific theory. I'm a journalist, and report on discoveries and try to express the scientific consensus.

[@everettputerbaugh3996]

Goronak: Oh no! Shades of 3001: A Space Odyssey -- A Dyson ring with elevators evenly spaced about it down to the surface.

[@JamesCairney]

Hadante good answer

[@flying_shawn]

The answer to the equator question made me curious: have any satellites ever been launched directly *opposite* of the Earth's direction of rotation? I can't think of any reason why someone would want to, but maybe there's some really unorthodox mission profile out there that'd justify the delta-v penalty?

[@pmm0107]

In talking about the Big Bang, you said "the Universe was more dense in the past, will be less dense in the future". At what speed did the expansion happen in the very early stages, say, the first million years?

[@crispico4727]

Could the expansion of the universe some day overcome the forces between quarks? Wouldn't thag result in a sudden influx of infinite new quarks?

[@frasercain]

If the rate of dark energy increases, then yes, it'll eventually tear apart quarks and even black holes.

[@SimonAmazingClarke]

Hi Fraizer, I think it was Scott Manly that mentioned a sling shot mission around the sun. There is a specific name for this one. You go to the sun with more mass, just before you stop accelerating you turn on an engine and continue accelerating until the fuel is used, therefore leaving the sun a lot lighter than when you arrived. Can you remember the name of that manoeuvre?

[@frasercain]

It's called an Oberth maneuver.

[@SimonAmazingClarke]

@@frasercain Thank you.

[@DavidChipman]

About the Voyager 2.0 idea, I have wondered if anyone might do missions to each of the larger planets with many moons, to take close looks at each of those moons.

[@ThePsyko420]

Speaking of orbital velocity, a question occurs to me, in terms of the sidereal day(ie:what would be the duration of a single rotation) how fast would the earth have to rotate in order fling off it's crust?

[@saiprem]

QUESTION. If the entire energy of the cosmic microwave background was converted into mass, how would that mass compare to the mass of the universe?

[@caerdwyn7467]

Belote... Given Starship's cargo hold length of 17m, theorize a folding telescope that has three mirror segments end-to-end (one in the center, two "wings")... assume segments that are 6 meters by 15 meters, yielding an unfolded/locked mirror that is 6 meters by 45 meters total. What are the limits imposed by the non-circular mirror profile? Do you think the simplicity of three rigid segments simply hinged together, with just the two segment boundaries to mess up refraction, is enough of a benefit?

[@takanara7]

Stuff needs to be aligned at the nano-meter level so nothing about it is going to be 'simple.' The JWST's design is fairly 'simple' what made it so expensive was cutting down the weight to almost nothing. So for example their sun-shield needed a special clean room because it was made from super-thin material but if they'd made it from thicker material it'd be a lot cheaper.

[@douglaswilkinson5700]

At Vancouver, B.C. the Earth is rotating at about: 1670 km × cos 49.3° North = 1089 km (where 1670 km is the speed of Earth's rotation at the equator; cos is cosine; 49.3°North is Vancouver's lattitude; 1067 km/hour is the speed of the Earth's rotation at Vancouver, B.C.)

[@greggweber9967]

In launching to a lunar orbit from Earth in order to get a slingshot, can you aim for a Lunar pole so that the inclination will change and you can go away from the ecliptic?

[@aalhard]

21:10 We are all the ship of Theseus

[@mikeullrich9792]

I often hear about the speed of light "speed limit". What doesn't connect with me is what happens if "something" hit or tried to pass that speed limit. In other words, if there were a way for something to be "infinitely" accelerated, why would it not pass the speed of light and what would happen it is tried? Is there even any way we could know if something other than light hit or surpassed that speed?

[@GhostofReason]

Light travels at the “speed of light” because that’s the fastest that anything CAN move. The speed of light is actually the speed of causality; it is the fastest that any action can happen.

[@logansmall5148]

How do you keep accelerating when your accelerant can't go faster than the speed of light? :p

[@jackturner8472]

well it would have to go... faster than light, for us to notice. try and notice something going half the speed of light, not even remotely possible with our best computers. the speed of light is really the limit of energy, if takes too much energy to go faster than light (it may be easier to accelerate space-time ftl), and even if there were craft going ftl they are practically invisible

[@patrickgriffiths889]

It's simply not possible.

[@larscarter7406]

I just wonder, say, in a galaxy that was moving near the speed of light according to earth time, launched an object from a planet, would we be able to see it? If it is moving past the speed of light from us, then we can't interact with it unless it is slowed down. I think it's the same for particles. If they are moving really fast, you can't tell if they are really there or what position they are in until you slow them down.😊

[@davesilkstone6912]

Can you clear my confusion? The evidence for the acceleration of the expansion of the universe is that objects further away are moving away faster, but as you look further away you are looking back in time, so the universe was expanding faster in the past, why don't we say that the expansion is decelerating over time?

[@FloatingInZeroG]

Question: How do meteors interact differently with each of the planets in the solar system?

[@dougirvin2413]

Hi Fraser, is the agonizing latency on intercontintal interview shows (Al Jazeera news comes to mind) the result of the speed of light just being to slow for the modern attention span, or is it some hardware/software issue that could eventually be remedied through engineering advances?

[@AlexKnauth]

(Alaris) The stuff around the epoch of re-ionization that you're referring to as opaque... was it opaque to all wavelengths? Or was it transparent to some wavelengths that just aren't convenient to build giant telescopes to detect? I've been listening to Katie Mack and John Green's podcast on the history of the universe... and what Katie Mack said and what you said here didn't seem to match. What I heard there was like: 1. Before the CMB Recombination: dense plasma, opaque to all EM radiantion, basically everything except Neutrinos and GWaves. 2. After CMB but before Re-ionization: dense gas, not ionized, transparent to what was then visible light but is now radio waves, but opaque to what was then higher-energy EM radiation that is now visible light. So radio telescopes can see through it but optical telescopes cannot. I'm not sure whether infrared telescopes have more of a chance or not... even if JWST can't, what about a further far-infrared telescope than that? 3. After Re-ionization: less-dense plasma, transparent to more things from radio through infrared, visible, and ultraviolet. Not broadly opaque unless it's a particularly dense region, though there are absorption lines we can see where they're opaque to specific wavelengths, they're not opaque to broad ranges of frequencies outside those absorbtion lines. With that context, my question is: After CMB but before Re-ionization, when there was dense gas, not ionized, what wavelengths of light would it be transparent enough for us to see, and what wavelengths would those be redshifted to, that we could build a telescope to observe? (3:23) oops I wrote all that before I listened to the 2nd half of this answer

[@frasercain]

No, not all wavelengths, there are proposed observatories to help probe that era

[@kurtgrossman6384]

Question: Are Lagrange points litteral points in space? If you put a big enough space station there is it then fully occupied? Or are they continuous points on a line between two centers of mass? If it is a point does it follow the elliptical orbit a smaller mass has around the larger mass? Do they a have an elevation above or below something like the plane of the ecliptic?

[@frasercain]

They’re more like a large zone that changes depending on the positions of the Earth, Sun, Moon and other planets. You can never be perched perfectly because it’s always moving

[@Christheonetruechris]

Dear Frasier, If Phobos is on a collision course with mars. Could it's gravitational pull reinvigorate Mars's core/electromagnetic field? Much like how Jupiter keeps some of it's moons geologically active? Or is it necessary to have a massive collision such as Earth and Thea to create such a magnetosphere as Earth has?

[@Christheonetruechris]

What if we cave Phoebe a gentle nudge? How could that affect future efforts to terraform mars?

[@bjornfeuerbacher5514]

Phobos is _very_ small. Its gravitational pull on Mars is negligible.

[@magnesiummike]

Is it possible that the laws of physics change over time?

[@waqqashanafi]

Yes, immediately before the big bang.

[@bjornfeuerbacher5514]

I think it's hardly possible to answer such a question in a scientific way.

[@deuce2669]

Maybe going back in time and saving the whales! My favorite Star Trek movie!

[@GeorgeStar]

Mind boggling to think that for 380k years the whole universe was basically a giant star!

[@bjornfeuerbacher5514]

Actually, the universe was like the _surface_ of a giant star for most of that time. In was only like the _center_ of a star for a few minutes.

[@charjl96]

Hi Fraser, could you explain how horseshoe orbits work?

[@sterrre1]

Anton had a video in which he was discussing the discovery of a very, very early galaxy where most of the light came from glowing gas instead of stars or blackholes. Is that related to reionization?

[@frasercain]

Sort of. That galaxy has a lot of primordial gas around it, which make stars similar to pop3

[@marccunningham4375]

I have no question so, Alaris.

[@Christheonetruechris]

How much energy is necessary for for Hubble or JWST to remain at the L2 Lagrange point every year?

[@bjornfeuerbacher5514]

No energy at all?! Both telescopes are essentially in stable orbits. (Hubble's orbit probably decays a bit with time due to friction with the atmosphere, but that's negligible over its lifetime.)

[@ThePsyko420]

Before you get into I always figured frisbees on the moon would have a similar trajectory to a ball on earth. But I never cared enough to look into it

[@HansMilling]

If a rocket is exposed for weeks with the +/- 200c, many, many times. Wong that put a lot of stress on the metal, expanding and contracting many times.

[@ReedCBowman]

"Titan Disc Golf" merch when?

[@jeremysart]

Ok, here’s a question.. maybe a dumb one hopefully not.. but if something like a star can become so dense and heavy that it could collapse into a black hole, what prevented the early universe from collapsing under its own mass and gravity when it was condensed to the size of a grapefruit?

[@bjornfeuerbacher5514]

The early universe was very homogenous. So the gravitational forces pulling into different directions cancelled each other out. Additionally, when one talks about the universe being "the size of a grapefruit", one does not mean the _entire_ universe, but only the part of the universe which is observable today.

[@Anubisuicideify]

Question: Was there a time in the past where IF we had a powerful enough telescope we could see the "Big Bang" taking place or is the cosmic background the best we could have ever done?

[@bjornfeuerbacher5514]

As Fraser explained in the video, we can't see past the CMBR. That has nothing to do with how powerful our telescopes are - the universe simply was opaque before that time, light could not travel freely.

[@greggweber9967]

15:30 Why can't you use the modern version of when they used VCR tapes to record one wavefront as it passes by and then the same front coming from another point of the spread out image that was bent by another portion of the foreground galaxy lens? Looking at a dot beyond the foreground lens, should you see the dot traverse from one picture to the next rather than disappear here and appear there? (The Astronomers episode about John Dobson)

[@popolpolpolz]

question. what is conscience? To call something "alive" what do we neeed? Do we need a heartbeat or conscience? or do we need both? are blackholes alive? conscient? can matter be conscient? we are matter after all...%? can anti matter be conscient? are blackholes alive?

[@jasonalpha]

Great show thanks I have a question; I've heard Neil deGrasse Tyson say that if you go through a black hole or maybe it was a wormhole that you could end up in a different universe or a different time. Does this mean that the very nature of time has been discovered because surely it must be a physical thing in order to allow movement back and forth , what do you think ? Thanks . Jason

[@bjornfeuerbacher5514]

What do you mean with a "physical thing"?

[@saquist]

Remember the tale of Neil Degrass Tyson who said "A Private Company can't take the place of NASA because it cost too much!" Then came Space X.... Fraser Cain at 34:30 "You can't make money in space", until one day you can. We already have starlink making vast amounts of money in space. This is about finding the right business model and perhaps astronomers like us aren't the ones to that understand logistics, supply chains and economies of scale to make that judgement

[@frasercain]

I specifically said that there wasn't a business model beyond low Earth orbit. That's because this is where we live.

[@jamesleatherwood5125]

I straight commented that we needed a purpose buit interstellar explorer on your last spacebytes video, then boom, here i find that we are. lol

[@frasercain]

Hah, you and NASA are of one mind

[@mjvalles00]

Hadante.

[@harabanar7827]

Hadante 🤘

[@KayveMusic]

You never mentioned how significant the very low gravity of the moon would enhance the distance you could throw a ball the same weight as a frisbe.

[@SteinMole]

After the first stars (gen 3) got into existence, wasn't there a very long time until these collected together in galaxies so there should be a time we might be able to see no galaxies but only free floating stars?

[@frasercain]

They were surrounded by all that gas and dust. Once they'd cleared out the dust, they'd already died, making way for the next generation.

[@SteinMole]

@@frasercain thanks Fraser, but then my question would be applicable for gen 2? But I guess by then galaxies have already formed, right?

[@SteinMole]

Ergo the first thing we will ever be able to see is completely formed galaxies, nothing prior

[@jackdowling4606]

​@frasercain What is the dividing line between population 3 and 2 stars?

[@takanara7]

@@jackdowling4606 Pop-3 stars have never been directly observed. A pop-3 star has to be made from pure hydrogen-helium with no 'pollution' by heavy elements.

[@jackdowling4606]

Is there any experiment that we could carry out at the moment, with current technology, to prove / disprove Hawking radiation? If not now, then what would be a theoretical way to do so, hopefully this century?

[@bjornfeuerbacher5514]

Some experiments already were done, which essentially used sound waves instead of light and something analogous to a black hole, but which absorbs sound waves. And these experiments already have shown that in these cases, something like Hawking radiation indeed exists.

[@larscarter7406]

Maybe the big bang should be called spontaneous combustion.😂 It just happens.

[@ElyonDominus]

Spontaneous Cosmic Combustion.

[@everettputerbaugh3996]

Edora: Does anyone remember the last episode of "Space Force"? Some asteroids are stainless steel (iron and nickel). Hummm.

[@jeremysart]

28:11 true but harsh haha

[@jamesleatherwood5125]

You dont need the planets lined up with ion engines. just gotta keep em on fer a while! :P

[@frasercain]

It’s a boost, whether you use chemical rockets or ion engines

[@brandonspirito]

What is the shape of the universe and why did it end up that way?

[@robbumusic]

A vote for Chulak, because saving the whales by solar slingshot.

[@Maelthras]

Chulak. Technically, couldn't every large object in the solar system be used as a gravitation assist. Do they need to line up or can they still be used if the probe has to say, cross a quarter of the orbit of the sun from each object. Taking longer to gather more speed.

[@DustinCable]

Question: What's crazier, a point of infinite density or some unknown form of degenerate matter at the center of a black hole? Seems like the singularity is the go-to answer, but isn't that more problematic than just extending the white dwarf and neutron star pattern?