Messaging The Aliens, Moving the Earth, Shapes of Coronagraphs

Messaging The Aliens, Moving the Earth, Shapes of Coronagraphs | Q&A 258

Рет қаралды 33,551

Күн бұрын

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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Пікірлер: 247

@marcusm6104 14 күн бұрын

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?

@JanaPersson 25 күн бұрын

Great content! Love your enthusiasm and your commitment to encourage curiosity and discovery. All the best from Sweden.

@thedenial 26 күн бұрын

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.

@earlworley-bd6zy Күн бұрын

Another way to send a message ?maybe get a answer? is a gamma ray emiter using 1's & 0's .,Because no type of star uses gamma ray binary bursts ever.

@alexjustalex_ 26 күн бұрын

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!

@smeeself 26 күн бұрын

Next to the thumbs up/down, there is usually a button that says "Thanks". That's what I use for one off donations.

@kevincooper1305 20 күн бұрын

Vulcan. Beautiful description Frasier

@manoz6194 26 күн бұрын

Giant Dorito orbiting the sun, Aliens would definitely visit us!

@RanjakarPatel 26 күн бұрын

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.

@justfellover 26 күн бұрын

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!

@oldtimer2662 25 күн бұрын

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 🤮

@blimfark875 25 күн бұрын

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.

@alexanderreintzsch5315 25 күн бұрын

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.

@zaphodbeeblebrox1153 26 күн бұрын

Thanks mate. Great episode, very interesting and easy to follow. Appreciate your work. 👍

@qaaronpeasron8996 26 күн бұрын

Have a good travel!

@jeffborders1146 26 күн бұрын

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.

@charleslaurice 26 күн бұрын

You are an amazing teacher 👍

@rwarren58 26 күн бұрын

One for the algorithm. Keep up the great work.

@frasercain 26 күн бұрын

All hail the algorithm

@timpointing 25 күн бұрын

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!

@melantorja 25 күн бұрын

safe travels friend, we look forward to more of your wisdom

@swiftycortex 18 күн бұрын

@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?

@filonin2 17 күн бұрын

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.

@charleslivingston2256 25 күн бұрын

Risa. It is amazing how much neutrino detectors have improved (both sensitivity and directivity)

@trelligan42 26 күн бұрын

#Andoria Good question, excellent answer. #FeedTheAlgorithm

@Threedog1963 8 күн бұрын

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.

@michaelpettersson4919 13 күн бұрын

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.

@dustinking2965 25 күн бұрын

Have a good vacay!

@JurijSlavec 26 күн бұрын

Andoria for the answer, really cool.

@mshepard2264 23 күн бұрын

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.

@Flowmystic 25 күн бұрын

thanks for the moon illusion tip and bless your kind heart to send them a microphone for the interviews if needed.

@adamredwine774 26 күн бұрын

Risa... My PhD research is in neutrino studies. The neutrino supernova warning is an awesome idea. I love it.

@aurtisanminer2827 23 күн бұрын

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.

@mcnaire2004 26 күн бұрын

Another good one

@TeamAgainstWild 25 күн бұрын

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..

@Xostrich12X 26 күн бұрын

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?

@MrAlefloo 26 күн бұрын

Best channel on the tube

@frasercain 26 күн бұрын

Aww, thanks

@JAGzilla-ur3lh 25 күн бұрын

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!

@JurijSlavec 26 күн бұрын

Is Uranus a captured rogue planet? What could explain it's weird inclination?

@Greeen7771 25 күн бұрын

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.

@filonin2 19 күн бұрын

Yeah, large impact. A captured planet wouldn't be in the plane.

@phooogle 26 күн бұрын

I do like the idea that we'll still be around in 500 million to 1 billion years to raise our orbit :)

@timpointing 25 күн бұрын

[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.)

@ryanschmitz3198 26 күн бұрын

Do you have a better link for Ian Lauer's channel? The one in the video description doesn't take me there

@ninatolfersheimer 25 күн бұрын

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! :)

@terryharding4185 21 күн бұрын

Gotta go with Vulcan this time

@michaelmcchesney6645 25 күн бұрын

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....

@nadyan9525 26 күн бұрын

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?

@user-kg4fr9jr7v 25 күн бұрын

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

@christopherleveck6835 22 күн бұрын

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.

@frasercain 22 күн бұрын

Great timing!

@douglasstrother6584 23 күн бұрын

"Message In A Bottle" ~ The Police

@glyngreen538 25 күн бұрын

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.

@BigTinkerer1 26 күн бұрын

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"...

@ahlynka1 26 күн бұрын

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.

@erictaylor5462 21 күн бұрын

I just realized, you'd se the sunrise and the sunset at the exact same time.

@davidva8694 26 күн бұрын

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.

@kenwhitmore210 13 күн бұрын

One huge green tetrahedron!

@hipser 22 күн бұрын

Great lunar eclipse correction. Though.. I feel it's absolutely necessary to posit that Lunarians would call our lunar eclipses solar eclipses :P

@HansEirikRd-dp8ry 22 күн бұрын

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?

@Greeen7771 25 күн бұрын

Andoria. How big would planets/moons that formed around sub-brown dwarves be? What might their systems look like in general?

@stuartreed37 26 күн бұрын

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

@frasercain 26 күн бұрын

You see the complaints we get. 😀

@stuartreed37 26 күн бұрын

@@frasercain yeah I mean nothing wrong with quality control I suppose but definitely don't let negative comments get to you :)

@davidva8694 26 күн бұрын

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,

@Ahuka 25 күн бұрын

Aeturen

@JamesCairney 26 күн бұрын

Vulcan I think that answered it

@zbyseklegindi5017 26 күн бұрын

Thank you. Question: Have we any chance to defend our solar system agains rouge Earth size planet ?

@Raz.C 16 күн бұрын

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?

@Jameson1776 26 күн бұрын

I’ve never once seen the planet name. I’ve been watching for years.

@hervigdewilde3599 24 күн бұрын

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.

@ruspj 24 күн бұрын

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 ?

@000fisherman 26 күн бұрын

in regards to "can we see supanova in real time" is eatleguise being monitored 24/7 for hnutrinoes???

@shanephillips4011 13 күн бұрын

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.

@jonathanbyrdmusic 25 күн бұрын

Gratuitous Gaia mention™️

@cleetussnow7159 26 күн бұрын

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.

@CruisinComPTon 26 күн бұрын

How about a green reflective triangle(s)?

@justfellover 26 күн бұрын

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.

@jack504 15 күн бұрын

Aeturen Cosmic expansion causes red shifting of photons. Red shifted photons have less energy. How is this squared with conservation of energy?

@mechadense 26 күн бұрын

A luar eclipse from the Moon has actually been recorded IIRC by that Japanese lunar sattelite with a HD cam on it IIRC.

@hamii91 26 күн бұрын

Do mirrors on a telescope need to be circle shaped? Seems cheaper to just make a curved line that is rotating in space.

@DominikJaniec 26 күн бұрын

rotation sounds like a lot of vibrations...

@justfellover 26 күн бұрын

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.

@filonin2 19 күн бұрын

Yeah, the mirror needs to exist to reflect light.

@gemstone7818 26 күн бұрын

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

@tonytaskforce3465 26 күн бұрын

Alien: Oh look, those monkeys in a galaxy far far away are waving bottles at us. Alien 2: Wow.

@trelligan42 26 күн бұрын

Alien 3: Awww! So cute!

@tonytaskforce3465 26 күн бұрын

@@trelligan42 Alien 2: Perhaps they're inviting us over for a drink. What do you say?

@cabodiansmyte 8 күн бұрын

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

@MrAluntus 21 күн бұрын

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!

@frasercain 21 күн бұрын

Check it for yourself. 😀

@hoefty232 21 күн бұрын

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?

@frasercain 21 күн бұрын

It doesn't affect the measurement much, but it's what allows astronomers to know the direction and speed stars are moving.

@corneliusstein9117 24 күн бұрын

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?

@MacarthurLouissaint-rz7tl 19 күн бұрын

Can you do a video on subspace communication??

@frasercain 19 күн бұрын

What is that?

@MacarthurLouissaint-rz7tl 19 күн бұрын

FTL communication

@CharIie83 25 күн бұрын

isnt it possible to detect life on distant planets?

@benellison5668 20 күн бұрын

Have you addressed UAPs and the prior Congressional hearings?

@hugegamer5988 25 күн бұрын

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.

@Goatcha_M 26 күн бұрын

I always thought the bigger Moon lower down was a lensing affect. Interesting that its optical illusion.

@gordonborsboom7460 26 күн бұрын

Could a sun shade be utilized with or added to the orbit of JWST to enhance its planet finding.

@ChrisBrown-iu8ii 26 күн бұрын

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?

@frasercain 26 күн бұрын

KZfaq has a pretty good transcript

@markfindlay8636 26 күн бұрын

Have you not seen independence day 😢

@melantorja 25 күн бұрын

VULCAN!

@thedenial 26 күн бұрын

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*

@jamiefields8145 26 күн бұрын

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?

@filonin2 19 күн бұрын

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.

@HPA97 16 күн бұрын

Aaeturen: Could we be protected from a nearby supernova if there is a black hole in-between us and the supernova?

@acestapp1884 21 күн бұрын

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?

@frasercain 21 күн бұрын

Earths geode would probably introduce too much noise

@BabyMakR 25 күн бұрын

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.

@jfeeney100 26 күн бұрын

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).

@randalptashinsky3272 25 күн бұрын

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?

@EamonnLawler 25 күн бұрын

Soup to nuts? That's a new one! Anyone else heard that phrase before?

@benellison5668 20 күн бұрын

Regularly hear this phrase. 500x plus

@filonin2 19 күн бұрын

@@benellison5668 On what planet?

@aracoixo3288 24 күн бұрын

🎉🎉🎉

@JenniferA886 26 күн бұрын

👍👍👍

@TheMsPetal 24 күн бұрын

Andoria

@seditt5146 25 күн бұрын

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.

@frasercain 25 күн бұрын

There is a proposal to try using one for an existing ground based telescope.

@czerskip 26 күн бұрын

"A series of images stitched together to make a movie" is literally what a video is… 😅

@frasercain 26 күн бұрын

Yeah, but it won't be 30 fps

@testboga5991 26 күн бұрын

Green laser could also work if it's aimed well

@michawnuk8114 26 күн бұрын

How would you know where to point 🤔

@justfellover 26 күн бұрын

You could start with the star systems mentioned as inhabited in our ancient stories. Or you could carry on aimlessly for thousands of years claiming it would be foolish to attribute any legitimacy to these stories, even though we have no other leads to pursue at all.

@filonin2 19 күн бұрын

@@justfellover That didn't happen though as we didn't know what stars were in ancient times. You might as well advise us to follow any random tale from that people made up back when they could not explain how things actually worked.