Rogue Gas Giant, Fish In Space, Detecting Primordial Black Holes | Q&A 212

What effect would a rogue gas giant have if it flew through the Solar System? Can fish survive in microgravity and go to space? Do hypervelocity stars leave a wake we could detect? How much do we actually know about Proxima Centauri? All this and more in the week's Q&A!
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00:00 Start
01:08 [Tatooine] Can life exist on an Earth-sized moon of a gas giant?
06:42 [Coruscant] Do hypervelocity stars leave a wake we could detect?
10:50 [Hoth] What's the thickness of the event horizon of a black hole?
13:16 [Naboo] What is the speed of gravity?
18:34 [Kamino] What would be the consequences of a rouge Jupiter?
21:44 [Bespin] Can fish go to space?
23:34 [Mustafar] What are the temperatures of black holes?
25:53 [Alderaan] How much do we actually know about Proxima Centauri?
27:29 [Dagobah] Can rogue planets have an atmosphere?
31:44 [Yavin] How to track possible primordial black holes?
35:44 [Mandalore] Does red/blue shift include all frequencies?
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[@supplychainoperationsresearch]

oh algorithm god, look upon us and spread this video around!

[@williamhaynie3738]

Ikr love this guy lol. He is great teacher fr

[@mizzshortie907]

Love how informative this video is

[@LordPhobos6502]

ALL HAIL THE ALGORITHM

[@fochdischitt3561]

"can fish go to space?" If you had a Death Star you could bring space to every fish.

[@onebylandtwoifbysearunifby5475]

I usually don't watch Q &A videos, but yours are exceptionally well prepared with a depth of information.. Well done Sir!

[@SomeMadRandomPerson]

How this guy only has 366k subscribers is beyond me!!! I mean, where else can you get amazing content like this and WITHOUT Ads!!!!! That's worth a sub and a like alone! Another brilliant video, keep up the great content buddy 😎👍🏻🏴󠁧󠁢󠁳󠁣󠁴󠁿

[@pauldavis1943]

Speaks volumes to the state of our "civilization" 😳

[@norml.hugh-mann]

Yeah, there is an overwhelming anti-intellectual bias in the youth...How can we expect any less as kids have always hated school, and now a large portion of the American population is attacking schools and teachers on a regular basis as enemies of the People while being used as political tools.. I'm sure it's damaged the children's interpretation of learning

[@SomeMadRandomPerson]

@@pauldavis1943 ain't that the truth!

[@doctormcboy5009]

word

[@Big.Ron1]

Coruscant is my favorite. Stars and bow waves. Black hole super velocity with a bow wave? Very cool. Hoth and event horizons is also right up there. Thank you and be safe.

[@ocoro174]

hell yeah. wish every day was Fraser day 🥰

[@scalplive913]

❓ "When you pass the event horizon of a black hole, assuming it's supermassive and not surrounded with an accretion disk, you won't even feel it". I have two questions about that; Actually those are problems rather than question, but the implicit question is:"Is this just me being ignorant or are those relevant to point out ? 1) When you pass an event horizon, all the photons will (from your point of view) be blue shifted to infinity (or plank wave length I guess). Shouldn't that obliterate anything going through an event horizon ? 2) Informaation can't get out of an even horizon. From my (very shallow and likely over simplistic) understanding, light (and therefore causality) can only flow downward. Doesn't that imply that, regardless of the tide effect, every particle of your body will be causally disconnected from each other ? (I guess "You won't even feel it" can also apply to instant death :p)

[@LucyAGI]

Isn't that what physicists have hypothesised ans called "firewall" ? (I'm referring to your second question BTW)

[@bjornfeuerbacher5514]

I think when he said "you won't feel it", he was only referring to the tidal effects. Not to the photons.

[@scalplive913]

@@bjornfeuerbacher5514 Yes. But that really dosn't seem like a minor detail. And I really don't understand why you wouldn't feel it even considering the tidal force. As a thought exeperiment, imagine a black hole's event horizon and your body, ignoring any photon. You pass the even horizon that, by definition, no information can go from inside to outside. Now consider your body half way through that event horizon. The half of your body outside can't receive information from the other half; in other words is causally disconnect from it. It's not the tidal force per say, still, your body can't exist as a whole and whatever object would be destroy by the fact every direction inside a black hole points towards its center. For the middle of your body, your head is in direction of the center, and your feet are.... in direction of the center. I won't bother you with a mathematical demonstration of that (which on the internet means: "I have merely a vague idea of what I'm talking about, but you can't be sure of that :p. But really, As a math nerd, I watched courses on the Einstein's equations solved in this kind of extreme setups, and my shallow knowledge and understanding of math lead me to understand (wrongfully so, most likely) that nothing we would recongnize as "something" could keep existing once the evcent horizon passed, because you can't really have causality inside an event horizon. everything just crushes into an infinitely dense point infinitely fast. And while I'm displaying my approximative knowledge of something that's beyond me, a singularity is described as an infinitely dense point in space only because that's what Einstein's general relativity predicts; but a lot of physicists believe that whenever an equation spits out an infinity, it probably means that you have reached the limits of what the equation can predict. That assumes that a lot of equations in physics are not right; rather, they're better approximation of how the reality behaves than the equations they came to replace)

[@gretchenmyers1279]

I am so glad I found your channel! Thanks so much for all the excellent content

[@realzachfluke1]

Welcome, Gretchen. Glad you found the place alright (⁠◍⁠•⁠ᴗ⁠•⁠◍⁠)

[@craigmooring2091]

The Coruscant query asked about two different phenomena, which your answer seemed to confute into one. He asked about a wake and about a bow wave. It was perhaps inviting the confusion to ask about them in that order. A bow wave occurs in front of a moving object; a wake is a phenomenon which follows it. To the best of my knowledge, there is no such thing as a BOW WAKE. Unless the boat is backing up.

[@BoyKissBoy]

I've ren binging these Q&As lately. They are so good! 😍

[@JoyThiefTheBand]

Tatooine: Also, the gas giant's magnetosphere might be great for deflecting solar flairs for a habitable moon from the red dwarf!

[@Markle2k]

Some good competition among the questions this week for “best”. I had 3 that I liked, 1 for the question, 1 for the answer, and with Bespin I liked both.

[@A.R.77]

I'm practically giddy being able to understand what is presented here. Big thank you to all involved.

[@johnbennett1465]

Fraser, here is a question for one of your experts. After a Star Shot probe is launched, the sail will experience a small amount of drag atoms hanging out in space. Eventually the small change in velocity will cause the payload to catch up with the sail. At that point the sail will wrap around the probe. This will block sensors and communication. The question is has anyone calculated the timescale that this would happen over. If it takes longer than the trip, then there is no problem. But if it takes less time than the trip, it is a big problem. Given the high speed of the probe, even single atom collisions will transfer a noticeable amount of momentum. In the lightyears it travels it will hit a lot of atoms.

[@ponyote]

A Pail of Air is a really fun short story that relates to the rogue planet phenomenon.

[@thingsandstuffwithinmebrai5938]

I don't mean to become an annoyance, but you said you needed questions 🙂 Can you delve into disappearing stars that change instantly into black holes a bit and explain how this happens/what it would look like up close

[@benjaminbeard3736]

Could you clarify your question a little bit? What kind of stars are you talking about, that turn instantly into black holes?

[@thingsandstuffwithinmebrai5938]

I see what you did there. Thank you. 🙂 I'll become a Patreon in the next week. It's deserved. Greetings from Kalamazoo

[@itsfahys]

Fantastic presentation, and Explanations that anyone with an interest in Astronomy can understand.

[@ioresult]

23:53 Three properties of black holes: mass, spin and electric charge. Magnetic field arises indirectly from those. Also from accretion disk. But not from the black hole itself.

[@OrenTirosh]

IIRC, a black hole has electric charge, but no magnetic field. The accretion disc can generate extreme magnetic fields, of course.

[@cavetroll666]

Thanks for the content 🙃

[@SweetVictorE99]

I had a dream this morning that a gas giant found its way into near earth space and we all died :) Amazing timing on this thumbnail and title!!!

[@nathanegbert977]

Bespin. I don't know why but watching critters that can neither understand nor communicate learn how to manage themselves in microgravity is fascinating.

[@patrickdaly1088]

Maybe I've played too much Stellaris but when I read "Fish in Space" my first thought was Spacefish and Spacewhales, or the Starseeds from Larry Niven's books. Could life theoretically(as far as we currently know) get started somewhere in a cloud of organic molecules in space? What kind of adaptations would be necessary to survive in such an extreme environment?

[@Srfingfreak]

I really like the way you do journalism.

[@owenyoshida9202]

[Tatooine] a follow up question about exo-moon habitability: for a large exo-moon orbiting quite close to its planet, is it possible for the gas giant’s large magnetosphere to envelop the moon and protect it from solar winds? Also, I know earth’s magnetosphere has Van Allen belts where there is more radiation than usual, so could an unlucky exo-moon be made uninhabitable by its planet’s magnetosphere focusing radiation towards it?

[@moonrock41]

We know that the radiation environment around Jupiter is intense. If you could stand on the surface of Io without being burned by lava, but otherwise unprotected from radiation, you'd get a lethal dose in only a few minutes. The moons farther out are progressively less lethal, so that at Ganymede it's low enough that an underground base might be habitable. Callisto, while maybe not as interesting as the other moons would be the least dangerous spot in the Jovian system for a base. As long as a moon orbits the gas giant with enough distance it won't suffer damage, but that probably means it's not close enough to get any protection from its magnetic field. Ideally, the moon would have its own magnetic field, but such moons might be outliers.

[@echofloripa]

Best space show around!

[@TheyCallMeNewb]

Bespin. Fish in space! Good to learn that they didn't simply go crazy, rather, they adapted.

[@MaryAnnNytowl]

A well-deserved like and comment for the care and feeding of the ever-voracious Almighty Algorithm, here! Thanks, Fraser, for what you do for us all. ❤️❤️

[@kr4119]

Excellent question, Hoth.

[@hive_indicator318]

My fave was all of them. Each question/answer sparked a bunch of thoughts. Way too many to remember any, unfortunately.

[@foxrings]

Coruscant - Star Wake is my new favorite prospective band name.

[@commonsense-og1gz]

when it comes to tidal locked planets, i don't think the dark side would be uninhabitable, due to fluid dynamics. fluids always try to move heat from warmer to cooler locations. liquid bodies would have strong currents.

[@albertvanlingen7590]

That makes sense. Would be a rough place to survive.

[@commonsense-og1gz]

@@albertvanlingen7590 my apologies, i didn't see the typo, i meant to say uninhabitable. i think the fluid dynamics would allow for more thermal transfer to the dark side, like delivering water to a hot tub in the arctic. this would make the dark side more mild, but with stronger currents.

[@norml.hugh-mann]

​@@commonsense-og1gz iMO this would be applicable to areas near the boarder but depending on the size of the planet, the heat it's receiving and what medium is moving the heat around An eyeball planet would only have the closest region to the heat source able to support liquid water and even in the areas where light starts to diminish its already solidified where planets getting more heat might extend deep into the frozen side.. Like anythjng it probably has more variables to the equation than we even are aware of and it would be case by case

[@mechadense]

I wonder if there are exoplanets and exomoons out there covered in an liquid nitrogen ocean. And if Titan might have had one back when the Sun was still cooler.

[@9753flyer]

Somewhere in the universe I am sure at least one exists

[@Edwinvangent]

Thank you again.

[@microschandran]

Hi Fraser, the fact that blackholes event horizon increases as it swallows more mass proves that the matter at the singularity has to be present in center, and not gone into other dimensions, other universes, worm holes, etc as some hypothesize?

[@beyo5]

Fish in space would provide a good opportunity for aquaponics as a food source - assuming enough water can be acquired.

[@TraditionalAnglican]

Especially if you produced artificial gravity

[@MrVillabolo]

Bespin about fish in space. I've got a follow-up question about the fish issue. Can fish survive in moist air as well as zero gravity?

[@WalidDamouny]

Kamino. If a small black hole is orbiting a larger black hole in a region of tidal forces, will the small black hole be ripped apart like the moons that formed Saturn's rings or will its gravity keep it intact?

[@n-steam]

The problem with red dwarves and habitable exomoons: The HZ is so close to the red dwarf, which means any planet in the HZ will have a tiny Sphere of Influence for moons to be in. Big planets (like Jupiter) also have Roche limits extending further out. Leaving a much narrower band for moons to exist in than either Earth or Jupiter. Also big planets cast big shadows, so there won't be nearly as much "daytime" for half the year. Though I would be very interested in what mythology comes from a civilisation which began on an exomoon.

[@kenkalstein9424]

Coruscant gets my vote. Wow!

[@cypercharged5960]

Did the current neutrino experiments noticed any spikes in detection during the collision of neutron stars or any passage of gravitational waves? How precise enough is it to pinpoint with certitude the source event of the detected neutrino?

[@DavidsDreamFactory]

Do gravitational waves experience the doppler effect or something similar to red shifting? As our instruments for detecting them get better is there any interesting information that we could learn from the shifting of these waves that we couldn't learn from red shifting light?

[@wk8219]

Yes, gravitational waves will undergo the same red-shift as any wave that propagates at 𝑐. As the universe expands so will the wavelength of gravitational waves.

[@9753flyer]

They should according to physics, but our current equipment is not designed to detect it so we have not proven red/blue shift in gravitational waves yet.

[@tonywells6990]

Yes, and it makes the calculation of their masses more difficult to determine.

[@rkramer5629]

Bespin - Are there any plans for experimental centrifuge modules in orbit? Every time I hear someone talking about such things, they talk about material issues with trying to get at/near 1G but even a few percentage of a G could be a huge step forward

[@Disasterina]

My vote is Alderaan. Great video Fraser!

[@ioresult]

Black hole slash dark energy question here: if black holes inflate at the same rate as dark energy gets added to the universe, then that means black holes gain mass. That would counteract Hawking radiation losses. What's the breakeven mass where black holes gain mass at the same rate as they evaporate? (That would not be constant since expansion accelerates.) Also, if black holes gain mass and the galaxies are gravitationally bound, that means at some point every SMBH will gobble up their respective galaxy and keep inflating forever. Right?

[@mrxmry3264]

about those fish in space that were using light to determine which way is "up": didn't i hear that there is a cave somewhere here on earth with a dark ceiling and white sand on the floor, where the fish turn themselves upside down?

[@Kurukx]

Love the work Fraser. Im a dreamer too...What if :)

[@Voltion-]

Mandalore!!! 37:46

[@moofy69]

Yavin. i love everything more the older back we speculate If we started mining space rocks/planets/what have you, and bringing all the resources to earth, how much mass could we add to earth's before we started to have a measurable impact on it. something like changing our rotation, changing tectonic plate behavour, our gravitational footprint? im just curious how much space rock we could bring down before we cause problems

[@rickaustin2016]

One thing I would like consider is my opinion of the beginning of all the matter of the bigbang

[@richardr3984]

Hey Fraser thanks for everything you and the team do here! Ok question time. Space harpoons. Could we use them to attach landers/telescopes on passing interstellar objects like Muah muah for a free ride out of the solar system?

[@darkrazer1000]

Highly unlikely but imagine two SMBH`s both being ejected from different systems and colliding many years later?

[@collectorguy3919]

If they line up just right, with different masses, that could accelerate the 'lighter' black hole to what speed.

[@tjp353]

NASA should do a long term experiment with bombardier beetles in zero g - to see if the hypergolic little critters can evolve RCS.

[@martindecca6413]

Hello! i guess that my Q has more sense now, after the "Naboo" Question about the speed of G: if gravity works at the speed of light and the sun is moving trought the galaxy at a determinated speed, ¿earth is feeling the gravitational atraccion of the sun where it was 8 minutes ago? ¿does that have an influence over the shapes of the orbits? ¿what about things that lies light-months away like the Oort cloud bodies? Even further ¿what about Galaxies that are million of light years away?. Ty very much. As always, excelent content

[@petevenuti7355]

Personally I believe it would be far more likely to find a habitable Exo-moon then a planet similar to Earth. I honestly hold our moon responsible for making our planet habitable. For keeping the mantle liquid for a magnetic field due to tidal forces, for stabilizing our day and night cycle. Possibly even by ripping silicates off the surface in its formation causing a more iron-rich mantle for the magnetic field. A terrestrial sized Moon of a jovian body will have the same benefits and I believe would be far more likely to form.

[@zimmy1958]

Thanks

[@pauldavis1943]

Tatooine. Never thought about a tidally locked moon orbiting a tidally locked planet making it have day and night ( with eclipses)

[@pgg1509]

Kamino, Best question

[@joshlevas8076]

Are there ANY theories that explain the implications of earth being the only planet to produce life? Like for example the simulation theory (since it’s almost mathematically impossible for there not to be life elsewhere) may have a higher chance of being correct. Absolutely love the channel and all the work you put into it!

[@Seehart]

Red dwarfs have a huge disadvantage for supporting life. In the habitable zone they generate plenty of low frequency light to keep liquid water, but don't provide much low entropy energy for life (high frequency light for photosynthesis). There are alternative sources such as hydrothermal vents that provide low entropy chemical energy. Earth is a ball which absorbs a wide spectrum of light with plenty of UV and emits IR and an occasional Tesla Roadster with a huge net increase in entropy. The most fundamental characteristic of life is the capture and concentration of low entropy.2 The challenge is still that we lack the technology to locate the presumably huge number of earthlike planets out there. Unfortunately, the factors that make a planet detectable are not generally good for life. IMO earthlike needs to include the right kind of star, and therefore can't be in a close orbit.

[@pocketheart1450]

Tatooine - if you were in the twilight band at the day/night terminator on an eyeball planet orbiting a red dwarf, what color would the "setting sun" be and what color would the sky be assuming it had a normal habitable Earth-like composition?

[@chrisgasmith]

Re Tattooine, I’ve been wondering about binary planets as well. Eg two earth like planets in a binary orbit around each other on the trip around the red dwarf. I’d wondered if the probable tidal locking to each other would make their weather a nicer. Also I’d also be curious if the two magnetic fields would provide more protection from the more sporadic solar winds from a red dwarf

[@longboardfella5306]

Hey Fraser - you spoke about planets close to a red dwarf being tidally locked - we now know our Mercury is tidally locked in a 3:2 resonance to our sun so it actually still rotates over time - so my question is "under what conditions does a planet become tidally locked e.g. at a 3:2 resonance so that it actually still rotates relative to the sun"? I can't seem to get a clear answer on this and it might have big implications for life on such planets

[@NattyGainz]

Naboo because of your awesome answer Fraser

[@niehlsbohr]

Question: If there was a large sphere of water on some far future space station, and a suba diver in center blew bubbles, where would the bubbles go?

[@petevenuti7355]

Hoth , from what little I know about the math of passing through the event horizon is like either a continuous equation or a discontinuous equation depending on how calculated and for what frame of reference. That discrepancy seems like a self-contradiction? Does that observation provide any insights? or is it just another case of showing the nature of reality as a self-contradiction? You might need to bring in a theoretical physicist to answer that one.

[@mhult5873]

My vote: Coruscant . Thanks! :)

[@joshualeniger]

I like the idea of a "pandora" type moon orbiting a gas giant but what about the radiation from the magnetic field?

[@jonathanreyes1622]

Naboo: so will the planets orbit in the same circle or shoot out in a straight line

[@brobrah4595]

hey fraser! It seems like im always hearing about red dwarf (K and M type) stars in our search for life. is that because those are easier to see? it doesnt seem like we are focused on sun like (G type) stars. does that have anything to do with how bright they are, atleast in regards to the jwst? on another note has there been any new jwst information on trappist-f?

[@foxrings]

M&K dwarfs are frequently mentioned in the search for life because there are more of them. There are more M dwarf stars for the same reason there are more pebbles and sand than there are boulders in the world.

[@daithiodalaigh8914]

Cheers Fraser, Does the Goldielock zone need recalculating ? Since liquid water can exist in large gravity wells due to friction/tectonics on many objects and our understanding of life's ability to survive has expanded even to rocks only(?) but also extremes (from our perspective) of acids/temperature etc My guess : in 20 yrs we find signs of life everywhere ( well, lots of places, like exo planets, a few at first, 15 yrs, by 20 yrs scientists convinced. I bet 3 apples (easier calculate than inflation!) on that.

[@logicbug]

I would love to hear more about how exactly we can turn into a hulk with gamma rays 🙂

[@Threedog1963]

Makes sense that gravity can’t move faster than light. Because gravitational waves contain information about a merger between 2 large objects and information can’t travel faster than light.

[@alexdevey3188]

Bespin. I'm googling spiders in space. Awesome 🤩

[@leahdiston827]

Is there currently nothing beyond the microwave spectrum? Is that why we know it’s from the beginning of the universe? How do we know the CMB was red at the beginning?

[@dadsonworldwide3238]

Some how in the last 20 or 30 years we went from understanding the truly mind boggling odds of life to now our youth thinking it can be popcorn or something. Life under every rock and behind every telescope.. lol

[@nubletten]

If you do a scuba dive at night and loose the light and orientation, you very well think you swim up, but in fact you swim down. This is why i dont like diving at night. Also Bespin vote because i absolutely love fish, as aquarium pets, food and the magnificent creatures they are.

[@melantorja]

oh no i missed it this week!

[@pm7734]

Hey Fraser, great video as always! My question to you is....when the Cassini-Huygens probe arrived at Saturn all those years ago. How did it slow itself down to enter orbit? Did it simply bring enough fuel to fire its rockets or did it actually touch the atmosphere of Saturn and use aerobraking? Thanks!

[@bjornfeuerbacher5514]

You can find the answer on Wikipedia: "the engine fired to decelerate the craft by 622 m/s to allow Saturn to capture it"

[@Zungy24]

With the observable universe getting smaller due to the expansion of the universe, does that mean that the universe technically gets younger or stays relatively the same age from our perspective as time goes on? In another 13 billion years, there would be even less stuff to see due to red-shifting and ultimately falling over the cosmic horizon out of view, and the stuff on the very edge might still be only "13 billion years old".

[@ericv738]

Fraser, you always stress that clicking the bell icon will notify for the live shows. Well I'm telling you man, it doesn't notify me. I get notified for THIS video... But not the live ones.

[@frasercain]

Sadly that's the ironic joke I'm making each week.

[@ericv738]

@@frasercain oh. Didn't know you were being ironic. Thankyou for the reply

[@Drakcap]

@@ericv738 Neither did I :D

[@craigkilner1529]

I have possibly a dumb question.... is the event horizon the same for the escape of gravitational waves as it is for photons, i mean you said they were the same speed, and could you detect things theoretically gravitationally what is occurring in and around black holes that we couldnt necessarily observe otherwise?

[@Ken-rq9xr]

Cool show. Haven't got time for a intelligent question or observation. But looking forward to making you go Mmmmm?

[@robt8869]

Are non-black hole gravity wells catenary curves? When a giant dying star transitions to a black hole, does the geometry of its gravity well change shape? Like a curve bottom to a point?

[@mhult5873]

My question: how do we know that the measured Cosmic Background Radiation (CMB) temperature differences are not from galaxies, intergalatical gas or other objects at a closer distance than the CMB? How do we know that other varables don’t affect the CMB-temperature measurements? Thanks! Best regards

[@DavidJohnson-ww5qj]

Question: Would we be able to move asteroids (or the suspected core of a planet that never developed) closer to the earth to make it "easier" to mine? asking for a friend.

[@albertvanlingen7590]

...or clump a bunch of smaller asteroids together and build a space city holding them all together orbiting earth. That would be cool.

[@norml.hugh-mann]

Seems like the tech isn't developed yet for such

[@colinp2238]

Hi Fraser, do we have any way that we can calculate the total size of the entire Universe, or is that just something that is impossible to know? I think that a rogue planet passing through the Solar System or one of the solar planets being ejected may be the cause to the anomalies that we see in the Solar System, the situation of Uranus' orbit, disturbance in the Oort Cloud and the list goes on. The latter case of the ejection of a planet could also explain where our super Earth is. I often wonder if this planet was ejected by the movement of Jupiter, and maybe that SE bounced off Uranus, during it's exit.

[@bumlookercheekymonkey3985]

This dude reminds me of the guy hosts the podcast growing up in Scientology

[@poletooke4691]

Since rogue planets are so hard to spot, how do we keep our spacecraft safe when sending them on a long journey? Surely the chances are low, but non-zero, that it would smash into some unknown rogue planet?

[@AlexKnauth]

3:11 If a planet is close enough to its star to be tidally locked, isn't it really unlikely for that planet to have a moon? I see 2 problems with this: 1. The same tidal forces that lock the planet would make the planet's Sphere of Influence very small. Any moons outside that would be lost into orbit around the star instead, or never have the chance to form at all. 2. The planet's slow rotation rate would make the planet's Synchronous Orbit very large. Any moons inside that would tend to spiral towards the planet into its Roche Limit over time. At some point, stable orbits for potential moons would become impossible. Where would that boundary be, between possible and impossible moons?

[@snm359]

I would suspect that when two galaxies merge, if one of those galaxies has two supermassive black holes, you would then end up with one black hole potentially having the velocity to escape the merger. The three body problem.

[@ruspj]

curious about stras or black holes leaving a bow wake how sure are people that its a bow wake in front & tail behind the object? couldnt they just as easily be similar to how a comet with the equivilant to a bow wake facing the star & tail away from the star no matter what direction the object is moving?

[@bigianh]

How does gravitational assist work? I mean the energy has to come from somewhere or does it just appear to move faster because the probe isn't fighting the suns gravity as much?

[@nrg3k]

Question: what is the implication of the recent article about ‘universe breaker’ galaxies? If they look mature and are bigger, does that mean the age of the universe is significantly more?

[@frasercain]

I'm scheduling an interview with the researcher, so we'll find out together.

[@tonywells6990]

Short answer=no. It means galaxies are more evolved after a few billion years than thought.

[@Foshomoto]

If gravitational waves effect the fabric of space and light travels through the fabric of space and waves increases the surface area how can we accurately calculate distance with out also being able to observe gravitational waves that it traveled through?

[@Ginso21]

Good stuff Fraser, you're a coolio dooder

[@Enjoymentboy]

I've always wondered if there is a direct relation between a star's mass and its rotational velocity that would affect its ability to form a black hole. For instance if a star had no rotation at all what would the minimum mass be for it to form a black hole vs a star that is rotating at a high rate? If the star's equator was rotating at, let's say, 25% the speed of light, would the centripetal force (did I got hat one right?) essentially "fling" the star's mass outwards counteracting its gravity thereby allowing it to form a neutron star instead of collapsing into a black hole? And as the rotation of a neutron star slows down is there a point where it would suddenly collapse into a black hole once the gravity was able to overcome the outward force from the rotation?

[@poletooke4691]

31:30 How long would these waystations last before the rogue planet drifted too far off of the course to that star for it to be useful?

[@DavidGS66]

I've never seen a video analyzing if humanity, instead of relying on planet hopping, might just permanently live in interstellar space & colonize by crawlonizing the galaxy. Insterstellar space has H, He, dust, etc, material that can be mined. An ideal situation would be converting mater to 100% energy using E = mc^2.