Rogue Gas Giant, Fish In Space, Detecting Primordial Black Holes | Q&A 212
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- Опубліковано 19 чер 2024
- 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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You are free to use my work for any purpose you like, just mention me as the source and link back to this video. - Наука та технологія
oh algorithm god, look upon us and spread this video around!
Ikr love this guy lol. He is great teacher fr
Love how informative this video is
ALL HAIL THE ALGORITHM
"can fish go to space?"
If you had a Death Star you could bring space to every fish.
hell yeah. wish every day was Fraser day 🥰
I usually don't watch Q &A videos, but yours are exceptionally well prepared with a depth of information.. Well done Sir!
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 😎👍🏻🏴
Speaks volumes to the state of our "civilization" 😳
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
@@pauldavis1943 ain't that the truth!
word
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.
❓ "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)
Isn't that what physicists have hypothesised ans called "firewall" ? (I'm referring to your second question BTW)
I think when he said "you won't feel it", he was only referring to the tidal effects. Not to the photons.
@@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)
I am so glad I found your channel! Thanks so much for all the excellent content
Welcome, Gretchen. Glad you found the place alright (◍•ᴗ•◍)
I've ren binging these Q&As lately. They are so good! 😍
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.
I'm practically giddy being able to understand what is presented here. Big thank you to all involved.
Tatooine: Also, the gas giant's magnetosphere might be great for deflecting solar flairs for a habitable moon from the red dwarf!
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!!!
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?
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
Could you clarify your question a little bit?
What kind of stars are you talking about, that turn instantly into black holes?
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.
Fantastic presentation, and Explanations that anyone with an interest in Astronomy can understand.
I see what you did there. Thank you. 🙂 I'll become a Patreon in the next week. It's deserved.
Greetings from Kalamazoo
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.
Thanks for the content 🙃
A Pail of Air is a really fun short story that relates to the rogue planet phenomenon.
IIRC, a black hole has electric charge, but no magnetic field. The accretion disc can generate extreme magnetic fields, of course.
My fave was all of them. Each question/answer sparked a bunch of thoughts. Way too many to remember any, unfortunately.
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.
I really like the way you do journalism.
Best space show around!
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?
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?
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?
Bespin. I don't know why but watching critters that can neither understand nor communicate learn how to manage themselves in microgravity is fascinating.
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.
Somewhere in the universe I am sure at least one exists
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
Excellent question, Hoth.
Thank you again.
Bespin. Fish in space! Good to learn that they didn't simply go crazy, rather, they adapted.
Coruscant - Star Wake is my new favorite prospective band name.
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?
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.
❤️❤️
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.
That makes sense. Would be a rough place to survive.
@@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.
@@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
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?
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.
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?
Thanks
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!
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?
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?
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.
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.
Yes, and it makes the calculation of their masses more difficult to determine.
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
Mandalore!!! 37:46
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
[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?
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.
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
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.
Coruscant gets my vote. Wow!
My vote is Alderaan. Great video Fraser!
Love the work Fraser. Im a dreamer too...What if :)
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.
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
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?
Fish in space would provide a good opportunity for aquaponics as a food source - assuming enough water can be acquired.
Especially if you produced artificial gravity
One thing I would like consider is my opinion of the beginning of all the
matter of the bigbang
Highly unlikely but imagine two SMBH`s both being ejected from different systems and colliding many years later?
If they line up just right, with different masses, that could accelerate the 'lighter' black hole to what speed.
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
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.
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!
You can find the answer on Wikipedia:
"the engine fired to decelerate the craft by 622 m/s to allow Saturn to capture it"
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.
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?
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?
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.
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?
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
Naboo because of your awesome answer Fraser
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?
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.
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?
Kamino, Best question
Hoth(where I found myself asking...) Hey Fraser, ok so everything in the universe is spinning in whatever direction, conserving the momentum imparted upon it by all other means, and black holes are said to "framedrag" because of said spin. When it comes to Black holes, does the direction of its spin dictate what will happen to say a beam of light skimming(not entering) it? Like, if a beam is shone in the direction of its rotation would it pick up some momentum from the frame-dragging that is caused from the black holes spin, and get extra energy to either stay in orbit(including going to a higher orbit) or get "flung" out? Or if shone against the spin, would the frame dragging pull it into the black hole? What if its something other than light? Would it happen with anything if it does or doesnt happen with Black holes? I guess I'm just asking whether the spin of an astrological body has any noticable effect on the space-time around said body, besides its gravitational one?
My vote: Coruscant . Thanks! :)
Tatooine. Never thought about a tidally locked moon orbiting a tidally locked planet making it have day and night ( with eclipses)
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?
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?
If radio waves, visible light, gamma rays and all frequencies in-between are effectively the same but with different frequencies, what is it about a mirror that makes it reflect only visible light? Are there frequencies which are partly reflected and partly passing through a mirror?
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?
NASA should do a long term experiment with bombardier beetles in zero g - to see if the hypergolic little critters can evolve RCS.
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?
Bespin. I'm googling spiders in space. Awesome 🤩
Mustafar
How do we know the mass of black holes - is it based on the effect of their gravity on visible objects nearby? Since the laws of physics break down inside black holes, is it possible their mass and their gravitational influence are no longer "normal" (i.e. a mass that's way bigger or way smaller than the perceived gravity outside)?
Cool show. Haven't got time for a intelligent question or observation. But looking forward to making you go Mmmmm?
oh no i missed it this week!
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.
Hello, can the dark matter be the residual mass after being compressed to the singularity inside a black hole? That would means that we are living in a massive black hole and the dark matter is only the mass left there in it.
I watched your recent interview about the possibility that dark energy is generated as the universe expands through black holes. Which got me
thinking… is it possible that dark matter is dark energy after it coalesces/ condenses?
Has Chris Lange (question "Kamino") ever read the "Lensmen" novels by E. E. Smith? ;)
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?
Light has momentum. So, If a photon orbits in a perfect circle around a black hole, Defining the no way back height. Can a different photon orbiting in an ellipse go momentarily below that height? i.e. How well defined is the event horizon?
Question. A little bit confused by the answer to the speed of gravity question. Ok so they detected the gravitational waves and then they did the calculations and pointed the telescope where they thought the waves came from to see 2 stars colliding. If gravitational waves are the same speed as light by the time they pointed the telescope would the light from the event already have passed us?
Fortunately these events are visible for weeks.
Just a question is it possible that dark energy is the collective vibrations of atoms or even smaller particles
How possible is it to detect a rogue black hole if it was heading toward our solar system, especially solar mass black holes? Could we be surprised by one or would we likely have enough warning to react in some way to preserve humanity?
Naboo: so will the planets orbit in the same circle or shoot out in a straight line
I would love to hear more about how exactly we can turn into a hulk with gamma rays 🙂
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.
...or clump a bunch of smaller asteroids together and build a space city holding them all together orbiting earth. That would be cool.
Seems like the tech isn't developed yet for such
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?