Messaging The Aliens, Moving the Earth, Shapes of Coronagraphs | Q&A 258
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- Опубліковано 28 тра 2024
- How can we let aliens know we're here? What does a lunar eclipse look like as seen from the Moon? Can we record a supernova in real time? Why aren't coronagraphs just circles? Answering all these questions and more in this week's Q&A show.
Ian Lauer
/ @ianlauerastro
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00:00 Start
00:37 [Andoria] Can we signal to aliens with green glass?
06:39 [Vulcan] Lunar eclipse seen from the Moon
11:24 [Risa] Can we record a supernova appearing in real-time?
16:05 [Aeturen] Why aren't coronagraphs just circles?
20:53 [Vendikar] How do astronomers determine distances to other galaxies?
25:02 [Remus] Who was my favourite interview?
28:01 [Janus] How do astronomers determine the age of stars?
31:11 [Cait] Can we move Earth by the time the Sun will die?
34:31 [Betazed] Why does the Moon look bigger and yellow sometimes?
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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
Question: I’d like to know more about the nature of gravitational waves:
- do they “red shift” over vast distances?
- how are they effected while passing through a galaxy cluster?
- if we were able to detect them at a very small scale, could gravitational waves be used to interpret objects falling into a black hole?
Great content! Love your enthusiasm and your commitment to encourage curiosity and discovery. All the best from Sweden.
Cait: The idea of using repeated gravitational slingshots to change our orbit just beats out (Janus) using asteroseismology to *see* sunspots on the other side of the sun.
Just paused after you answered my question, thank you for taking the time! Fully satisfied with the answer, especially about red ring around the Earth, of which I wasn't too sure. Great animation too! And no there wasn't a third meaning to the question 😅As others pointed out, apparently totality would last about 30 minutes since that's what we see from Earth during a lunar eclipse. That would indeed be amazing to witness!
Can't subscribe to Patreon but I'd like to give a little something in return for support; I'll see if there's any way I can do that!
Next to the thumbs up/down, there is usually a button that says "Thanks". That's what I use for one off donations.
Thanks mate. Great episode, very interesting and easy to follow. Appreciate your work. 👍
The sun's primary output is around 500 nm, a wavelength described visually as being "blue-green" but mostly green. It would almost be safe to say most stars are actually green. The problem is green very quickly shifts to red or blue with distance. So the Sun would look more green if we get closer, but looks less green as you get further away. So while most stars of all sizes, even black holes, are mostly green, you have to be right up near their present position for it to shine through. It's not limited to stars. Earth is green. Not just with plant life. Look at those video recordings of the horizon from low Earth orbit. That's a green ionic discharge. The further away you get, the more red and blue it looks instead.
Remus: This was an awesome show and I liked a lot of these topics. I liked the Risa subject about the telescopes in space. But your view on the interviews was just touching a nerve. I love these interviews and I love it when there is this certain vibe to it. It's great to feel the passion of the both of you. And so many people are so humble about their part in the research and this is always getting me.
Vulcan. Beautiful description Frasier
Giant Dorito orbiting the sun, Aliens would definitely visit us!
Please ansur me question dear about how satellite video foto picture machine look four when Vishnu make many year before huminatarians? This little bit hurting four me and create sadness because I am different colour and countree but he no want make ansur four my colour paint.
Aliens: Does it mean they want chips because they maybe have too much dip, or that they only have chips and want us to send dip? If only we had more information about how they think!
Taco Bell has green Dorito 🤔
If we launched all the Taco Bell restaurants on Starships into orbit we should get all the Aliens to run away 🤣
It would make refuelling interesting too 🤮
Do we really want that? If they're anything like us, they would probably send a shotgun blast of tiny probes, traveling at relativistic speeds right through the solar system. I would prefer that we didn't risk the Earth being hit by one or more of those.
Have a good travel!
You are an amazing teacher 👍
Feeling sorry for Fraser's poor camera when he was demonstrating the parallax-method for determining stellar distances. "Do I focus on the face or on the thumb? Argh!" Hugs, little camera!
Cait
I think it would be easier to siphon matter off the Sun using star lifting and prevent it from dying since smaller stars last longer. You can then use that matter for building mega-structures.
safe travels friend, we look forward to more of your wisdom
as conceptually cool as the green star idea is I thin the Arecibo style targeted radio transmission way would be the most effective. starting with the closest stars. Might not be a great plan though.
@Fraser Cain it's thought that you could detect a Dyson swarm around a star by its infrared. My question is, wouldn't it also be possible for an advanced civilization with a Dyson swarm to be able to harness the heat and therefore eliminate the infrared? Or would it not be possible to harness all of the energy from the Star including the infrared heat?
Maybe put a green filter around another star. A small star. Something like Proxima Centauri.
Maybe use finely grinded green glass creating a dust cloud. There is no need to surround the entire sun, just in the direction of a suspected civilization.
Speaking of supernovas, I’ve heard quite a few times that a galaxy should see a supernova once every 40-50 years. And the last visible supernova in our galaxy was in 1868. Are we way overdue for another visible, naked eye supernova? Or do you think a few more have already occurred within our galaxy since then, but they occurred on the other side of galaxy and are just obscured by dust?
Is Uranus a captured rogue planet? What could explain it's weird inclination?
No and as far as i know it was a roughly Earth-sized icy planet that hit it around the poles and ended up tilting it.
Yeah, large impact. A captured planet wouldn't be in the plane.
One for the algorithm. Keep up the great work.
All hail the algorithm
Andoria; We should place a large rectangular structure with the ratio 1:4:9 orbiting the sun. That would freak the aliens out, especially if they've been monitoring the sci fi channel.
Vendikar. I've always wondered how space distance measuring works. I had it my head for a while that it was some kind of radar-type system in which you send out a signal and wait for the waves to bounce off the object and come back, but logically I know that isn't viable for objects that are properly far away. Thanks for the clarification!
#Andoria Good question, excellent answer. #FeedTheAlgorithm
[16:54] Also, more relevant to the problem at hand, a number of planets (Jupiter, Venus, Saturn, and Mars) should have been visible during the recent Apr 8 solar eclipse (I know that I've seen photos of this but I can't find an example right now.)
Andoria : Remus : Can we move out the earths orbit in order to avoid heat death,, was my favourite question and an interesting answer given that it should be easy if we are actually still around so far into the future / But in reality I really doubt we will be able to still exist more than a couple of centuries. particularly in our present meaty form..
Risa. It is amazing how much neutrino detectors have improved (both sensitivity and directivity)
I was imaging M101 when the supernova went off.
I took 900 x 30 second exposures that night.
About 300 light frames into the sequence is when it first appears.
Then it goes out. Then it comes back.
It does that four times before it starts to brighten and then continues to brighten for weeks before dying down again.
Great timing!
My mind was just blown. Wtf?? The early moon only looks bigger in our heads?? I thought it was magnification from the atmosphere. That is just nuts.
Risa...
My PhD research is in neutrino studies. The neutrino supernova warning is an awesome idea. I love it.
thanks for the moon illusion tip and bless your kind heart to send them a microphone for the interviews if needed.
Another good one
Reminds me of that sci-fi novel series where a rogue nanobot swarm is dismantling planets (inhabited or not) and creating trillions of algae filled satellites around each sun. And it’s spreading across the galaxy and none of the advanced alien races are able to stop it and there is an ever increasing portion of the galaxy where the stars appear green. Think it was suggested to have been intended for agriculture in a system but the AI had gone rogue and kept expanding.
I do like the idea that we'll still be around in 500 million to 1 billion years to raise our orbit :)
Andoria for the answer, really cool.
Have a good vacay!
The moon is farther away when we see it on the horizon than when it is right overhead. By the radius of the earth, and the moon is close enough so that matters.
So the moon is about 1.6% closer and bigger when overhead. This ignores the optical effects of the atmosphere.
I think the question about moving the Earth was rather about moving it via way described in The Wandering Earth movie. Digging deeper, taking the material out of the core and throwing it from titanic size ionic cannons direction opposite to what we intend to move in. And this actually gives a greated space for speculations whether it is possible. Because magma actually half liquid and it's interesting can we stabilize Earth surfacing taking out inner material making it eventually more hollow inside. I remember the estimate we should extract somehow about 10% of Earth mass to transfer it to higher orbit, but what would happen to surface if we extract 10% of liquid core is presumably not any good at all
It seems to me, If you live on the moon then a solar eclipse for the moon inhabitants would be a lunar eclipse for the earth inhabitants.
Maybe we could make a satilite of a fork and a spoon that are also sending out a code that says, "All you can eat"...
Hey Fraser! What are research projects one can carry out with a small backyard setup? I'm not thinking of cutting-edge science here, of course (though it would be exciting!), rather something like observing Leavitt's law or something along those lines. Appreciate your channel, keep the good stuff coming! :)
Wait, I have a follow up question to the flower-shaped solar sail thingo that's a partner to a space telescope. So they need to be at a distance to each other in order for the sail to block a star's light but not its planets. What happens when the telescope images a star's vicinity, and then needs to image another star - which device is the one that has to be re-positioned? Is it the flower-sail or the telescope? Or would they both orbit whatever common point they have and both move in unison to align to the next target?
"Message In A Bottle" ~ The Police
I want to vote for Remus as the best question, but I have a question about the planet for the coronagraph question. What Star Trek show/episode is that planet from? Did it only appear in a video game? That's all I could find via Google. It's not so surprising, given how little of the Internet is devoted to Star Trek....
Gotta go with Vulcan this time
Andoria.
How big would planets/moons that formed around sub-brown dwarves be? What might their systems look like in general?
would a lunar eclipse viewed from the moon be called something like a terran eclipse as it would be the earth eclipsing the sun rather than the moon ?
Do you have a better link for Ian Lauer's channel? The one in the video description doesn't take me there
One huge green tetrahedron!
Another cool way to tell it is an optical illusion. When you look at the moon on the horizon and it looks huge, just turn around, bend over and look at it upside-down between you legs, it will look small again like it was high in thd sky, seriously, its crazy.
Best channel on the tube
Aww, thanks
I just realized, you'd se the sunrise and the sunset at the exact same time.
Hi Fraser, great show! Q: The solar wind is shielding us from galactic cosmic rays, would not a dysonsphere mess with this? What consequence would the dysonsphere have on the solar system?
Lolz @AlexJustAlex for the cheeky double Q 👍
I couldn't find a real pic of a lunar eclipse from the Moon, but NASA did a 36 second CGI vid on YT, called *"September 27, 2015 Total Lunar Eclipse: View from the Moon"*
Nowhere near as impressive as the real thing, but it gives the general idea.
A fine mist of colored material in solar orbit might be enough too. Spread over a chunk of space it might alter the spectra to be noticed.
Thank you. Question: Have we any chance to defend our solar system agains rouge Earth size planet ?
Great lunar eclipse correction. Though.. I feel it's absolutely necessary to posit that Lunarians would call our lunar eclipses solar eclipses :P
A luar eclipse from the Moon has actually been recorded IIRC by that Japanese lunar sattelite with a HD cam on it IIRC.
Hey Fraser. Long time listener, first time questioner. I watched a Kurzgesagt episode recently (This Black Hole Could be Bigger Than the Universe) about the 'biggest black hole' and it was black holes all the way down. Cool theory, BUT Can you explain the difference between the mass of a black hole and the density of a black hole? That confuzzzled me
usually the way we find a star is by seeing if something blocks light in front of the star, if our sun emitted less visible light into the universe it would probably just hide us abit better since the wide area telescopes like tess aren't really equipped for IR light
Vulcan
I think that answered it
How about a green reflective triangle(s)?
Andoria : As stars are very inefficient in terms of energy production, wouldn't other intelligent civilizations figure this out too and not build dyson spheres but huge fusion reactors instead? So shouldn't we be looking for huge hydrogen blobs and planet sized fusion reactors?
Aeturen
Cosmic expansion causes red shifting of photons. Red shifted photons have less energy. How is this squared with conservation of energy?
Wild to me you have interviews you didn't post because of audio quality I wish I could listen to them are they on the patreon
You see the complaints we get. 😀
@@frasercain yeah I mean nothing wrong with quality control I suppose but definitely don't let negative comments get to you :)
Personally, the quality of the audio is less important to me than the quality of the information. I agree that you shouldn’t let negative comments down,
Hey!!
Shouldn't the Blue-Shifting of Andromeda, or alternatively, the Red-Shifting of other galaxies, couple with the Blue/ Red/ Yellow/ Orange light of various stars, such that some of them might appear green? Green light has a wavelength of about 525nm so any red-shifted blue stars or any blue-shifted red stars should at a certain point appear green, right?
If we're even gonna toy with the idea of starting a dyson sphere, we need to use clear glass and put green plants inside. The sphere will never be completed and it's purpose will remain questionable, but I can think of some good uses for orbital ecosystems.
I’ve never once seen the planet name. I’ve been watching for years.
A Dyson swarm (cloud of satellites) around a star is indistinguishable from a thick dust and debris cloud surrounding that same star. It’s not clear at all it would be obvious, maybe slightly unlikely.
Gratuitous Gaia mention™️
in regards to "can we see supanova in real time" is eatleguise being monitored 24/7 for hnutrinoes???
I always thought the bigger Moon lower down was a lensing affect. Interesting that its optical illusion.
Aeturen
Can you do a video on subspace communication??
What is that?
FTL communication
Gosh, I did not know that about the moon looking bigger as it rises. wow, now I feel like I've been fooled all my life!
Check it for yourself. 😀
Have you not seen independence day 😢
Aaeturen: Could we be protected from a nearby supernova if there is a black hole in-between us and the supernova?
Andoria. You could surround the sun with satellites in orbit but they could use that energy to shine green lasers as they orbit. Have satellites on different orbits constantly beaming these green lasers out would look like a lighthouse and would get a lot of attention.
Do mirrors on a telescope need to be circle shaped? Seems cheaper to just make a curved line that is rotating in space.
rotation sounds like a lot of vibrations...
A circle or something close to it is the way to get the most light onto the sensor. Other shapes add to the expense or just reduce the light captured, making the instrument less useful that it could have been. Your thin mirror slice would let most of the light pass whether you rotate it or not.
Yeah, the mirror needs to exist to reflect light.
Are the relative velocities between the sun and a star considered when using the parallax method to measure the distance to the star or is that just a known limitation in the method's accuracy?
It doesn't affect the measurement much, but it's what allows astronomers to know the direction and speed stars are moving.
Could a sun shade be utilized with or added to the orbit of JWST to enhance its planet finding.
Have you addressed UAPs and the prior Congressional hearings?
When we look at other star systems (distant or near) with our instruments, do we detect their oort clouds? Is the material that would make up theirs undetectable? Could they see what makes up ours?
VULCAN!
👍👍👍
Is there any way to use the starlink satellite ephemerides to do gravitational astronomy? Is it practical to gather any kind of scientific data from these huge satellite constellations?
Earths geode would probably introduce too much noise
Aeturen. How come all proposals I see for the Star Shade are for Telescopes in the pipeline? It should be a relatively easy project, if for nothing else a quick test type shade should be launched as an add on for JWST. Not only would it help them get data for a proper habitable worlds mission, but it would greatly enhance our observations of exoplanets right now. Idk, send it up with an Ion drive or something and just have it chase JWST observation schedule as much as needed. I am sure that with such a system Dr Kippings Exo-moon project would be finished on pretty much the first observation because without Starlight the only dip you would see are the moons.
There is a proposal to try using one for an existing ground based telescope.
Alien: Oh look, those monkeys in a galaxy far far away are waving bottles at us.
Alien 2: Wow.
Alien 3: Awww! So cute!
@@trelligan42 Alien 2: Perhaps they're inviting us over for a drink. What do you say?
Soup to nuts? That's a new one! Anyone else heard that phrase before?
Regularly hear this phrase. 500x plus
@@benellison5668 On what planet?
Cait!
OK, this is less than a question, and more of a proposal. Take two quantum computers running at the same time and running some sort of AI. Neither computer has a connection to the internet or to each other (they are islands). One Quantum computer is told to think about things, maybe a list of things can be submitted by people on the net that are things to think about. The second quantum computer is asked "What is the first quantum computer thinking about?". Can the second quantum computer guess what the first quantum computer is thinking about? How close can it get? Both Quantum computers are not connected to the internet or to each other in any way (Completely isolated).
isnt it possible to detect life on distant planets?
vendikar! what would the effect be if an ultra large solar flare were to hit Jupiter? Would it ignite Jupiter as a small sun? and if so what would the effect be on earth?
Why are type 1A supernovae always the same luminosity? How is the energy output always the same? Shouldnt there be some variance in the amount of source material from the stellar nursery that gives stars non-identical amounts of mass?
No as the collapse happens to a white dwarf that is gaining mass from a partner until it reaches the mass limit, which does not change. Picture it as a bucket filling with water that tips over when full (the mass limit), but only when full. Adding more mass after it has tipped is not possible as it has tipped/the star has exploded.
Black Hole Multiverse
A hypothesis by James Arasmith
I have not, nor do I know how to do the math to verify or falsify my hypothesis. I will, however, go through the logic behind my hypothesis based on my understanding of the science. If anyone can point out any mistakes in my understanding, or could do the math that could verify or falsify my hypothesis, please let me know. Thank you.
What I think I understand about the science
1. It is my understanding that within a black hole all directions in space lead to the singularity.
2. It is my understanding that within a black hole all of the black hole’s history is accessible.
3. It is my understanding that within a spinning black hole there is a toroidal shaped area of “normal space/time.
4. It is my understanding that elliptical galaxies contain mostly type 2 stars and have very little gas and dust.
5. It is my understanding that JWST found fully formed galaxies shortly after the Big Bang, galaxies that should not be able to exist so shortly after the Big Bang.
6. It is my understanding that the only explanation we have for the accelerated expansion of the universe is dark energy, something we have not been able to directly observe.
7. It is my understanding that the only explanation we have for the rotation of stars in the outer edges of galaxies is dark matter, something we have not been able to directly observe.
8. It is my understanding that particles exist in a probability distribution.
9. It is my understanding that, due to the nature of this probability state, a particle will interact with itself when passing through the slits of the double slit experiment.
My hypothesis
Given the nature of the double slit experiment, it is logical to assume that space/time is not 4 dimensional. Rather, space/time is 6 dimensional. 3 dimensions of space and 3 dimensions of time, where linear time is on the z axis, possibility is on the x axis, and probability is on the y axis. This would imply that gravity would warp, not only linear time, but possibility and probability as well. This could potentially be what leads to the collapse of the wave function.
The question is, if the particle exists in multiple places, is the mass/energy of the particle the same, actual mass in each of the positions or is the mass/energy divided proportional to the probability of its location? For this hypothesis, let’s assume the latter. The reason being, if gravity affects probability, the less probable state should have less gravitational influence.
So what does all this have to do with a black hole multiverse?
At this point, I will ask you to completely reimagine the Big Bang. Imagine a big bang that created the mass for just one galaxy. The mass expands and cools. After some time, gravity overcomes expansion. All of the matter in this universe is gravitationally pulled back towards the singularity of the Big Bang. Fusion begins at the center of the mass and the first star, a type 3 super giant, is formed. Because this star has the mass of the entire universe, it goes supernova very quickly, triggering the second explosion of the universe.
Because of the immense heat, the star does not release any gas. Rather, the supernova is an explosion of plasma. This plasma discharge forms droplets, the creation of second generation stars. These stars expand to form an ellipse. As the second generation stars eventually go supernova, they release gas and dust.
As expansion slows to a stop, the universe begins to orbit around the singularity at the center of the universe. A pinwheel pattern forms as all of the matter in the universe begins is very slow decaying orbit back towards the singularity.
Now, imagine this all taking place within the “normal” 4 dimensional space within a spinning black hole. What would we see when we looked outside of that bubble of normal space? We would see the entire 3 dimensional history of the black hole. We would see our universe’s probability distribution, a 6 dimensional probability distribution of a single galaxy. We would see the multiverse. And, because all directions in space lead to the singularity, the gravity of said singularity would cause the probability distribution to expand in all directions as the distribution is actually collapsing into the singularity.
This model would explain why we would see fully formed galaxies so soon after the Big Bang. Because, from the very formation of a Black Hole, its 3 dimensional time is accessible.
Note: I mention how elliptical galaxies and spiral galaxies fit in my model. But I left out irregular galaxies. This is because I’m not sure how they fit in. Originally, I thought they would form at the equilibrium between the expanding elliptical and contracting spiral galaxies. However, it is now my understanding that irregular galaxies have considerably less mass than other galaxies. Therefore, my best conclusion that would still fit this model is that they are the result of the probability distribution interacting with itself. In other words, they are the result of galaxy collisions.
Testing the hypothesis
First, the math: can Einstein’s field equations be modified for a 6 dimensional space/time on both sides of the equation? If so, does it fit what we observe in quantum physics? Does solving Einstein‘s equations for a 6 dimensional space explain dark matter?
Does the geometry of a galaxy residing in the toroidal normal space within a spinning black hole account for dark matter? Does it explain the apparent lack of mass?
Conclusion
I honestly doubt that my hypothesis is correct. Honestly, it’s an insane notion. However, it is an intriguing thought experiment. And if you have read this far, thank you for taking this thought experiment with me.
31:22 Fraser: We actually have a lot less than five billion years before there's going to be problems for life on Earth....
Me: *stares in climate change*
🎉🎉🎉
Frazer, For the invterviews with bad audio can an AI provide a transcript that you could review and then put that in as subtitles and release them?
UA-cam has a pretty good transcript
This (Andoria) and the Dyson sphere or any other idea of "covering the sun" are always hilarious. If you think about the very Earth upon which you step and is the best place to construct anything (without major inconveniences like lack of air or radiation) is but a tiny, nearly undetectable speck even from Pluto. We always underestimate the behemoths that are stars! I guess it's satisfies mental curiosity and is part of what makes us human. Dream on kids!
Andoria
"A series of images stitched together to make a movie" is literally what a video is… 😅
Yeah, but it won't be 30 fps