Great video Fraser. People have to remember that we are generally looking at short orbits with the transit method...longer orbit worlds will take more time to validate. A world exactly like earth orbit wise would take 2 to 3 years just to validate.
2-3 years just to validate its existence as well. If there was anything interesting, like a biosignature, expect confirmation for that to take even longer.
I love how you handled the question from the hopeful Mars colonist. Realist, honest, and being ready for unknown future opportunities. I also liked your KISS attitude for future space telescopes. Pragmatism FTW!
I took a bunch of astronomy + physics in school, so it's not like I've never been exposed to any of this, but I've been listening to a lot of space stuff like this channel on yt this yr and just the scale of everything in space from temps, to dist, to sizes, to time scales is so absolutely mind boggling and utterly alien to our daily existence
Thank you *so* much for answering my question about plate tectonics and exoplanets, Fraser. I stayed up late at night (Lisbon time) to catch the Q&A. I was only able to barely stay awake to ask my question and didn’t watch the rest of the show. I was anxiously waiting for the video to go live 😊. (I realize the patreon feed has the original video but I usually don’t look at it). Anyway, thank you so much. You’re my fav youtuber!
I find rogue plants super interesting. They are worlds we consider lost. Perhaps life can thrive in an isolated world. Scary thought to even imagine what the skyline actually would look like.
How does this channel not have more subscribers? I find the content fascinating and I particularly enjoy the Q&A videos. It must take a great deal of time and effort to research and create such an impressive volume of videos. You definitely deserve way more subs Fraser! Keep up the great work 👍
I suggested this on a Dr Becky video, why argue about how to pronounce Hycean, when we have a perfect replacement in Wet Giant. You know, Gas Giant, Ice Giant, and now Wet Giant. Other options; moist giant, damp giant, soggy giant. If we are sticking with Hycean, then surely it is pronounced like Ocean, but instead of Oh its Hi.
I really appreciate how quickly you jump in to the meat of your contact instead of advertisements, such Here’s a question you’ve probably answered 1 million times but I am ignorant and don’t know… How was the speed limit of light determined? What I mean is how does Einstein/others know that things can’t go faster?
It's an amazing story. An astronomer was looking at how long it took Io to go once around Jupiter and they noticed that over the course of the year that time changed and they realized it was because Earth was getting closer and farther to Jupiter and they're able to measure the difference and calculate the speed of light
@@frasercain hey cool story! What I meant was what is preventing the objects from going faster than the speed of light- chat Gpt told me that it was that you needed an infinite amount of energy to go that fast Even though I always watch your videos, I don’t usually like and subscribe to anything just because they pop up in my feed on my watch to the end… But I’ll subscribe to you right now, just for being awesome!
The question about plate tectonics was very good, as was your answer. I think it's possibly a prerequisite to life on this planet and could potentially point towards other life. But as you said, it is difficult to detect.
In regards to Betelgeuse going off, how would we receive neutrinos before visible light if nothing can exceed the speed of light? Does it release neutrinos just before it goes supernova?
And will I develop Superhuman Powers@@frasercain? Just me preferably, no one else... cos that'd defeat the object, and I'd just be left feeling "Super Normal?"
Nothing goes faster than light _in a vacuum._ Light goes slower if it isn’t in a vacuum. If the core explodes, the light from that has to penetrate several light minutes worth of not vacuum before it gets out into free space.
If the phrase "look similar to Earth creatures" means anything remotely coherent to you (not you specifically, Fraser, the generic you), you need to see more Earth creatures! Our biosphere has so much diversity and so many weird looking and weird acting organisms that we hardly even need to imagine aliens-just looking around ourselves should be enough to make us marvel at all the weird stuff! Evolution is an unguided exploration of the space of all possible life forms, of which we get to see one slice here, and other slices will probably look both similar and different.
Andoria - question about Hycean worlds. Vulcan - question about gravitational waves detectors. Risa - question about non-radio communication and the Fermi paradox. Aeturen - question about JWT looking for earth analog exoplanets. Hmm, difficult choice… can I say AnCaSEn Edit: As it goes along, I am adding more parts to the name. They’re ALL my favorite 😅
I loved your reply to the young person interested in going to Mars. people need to understand that it’s gonna take a huge industrial effort to make life work on Mars. So we need all kinds of people with all kinds of skills and attitudes and interests. I have a question for you. I would love to hear more about how you got into this kind of work. What did you study in school? Have you worked on any of the space missions previously?
Risa. I am amazed that there may be 70 candidates for instances of intelligent communications. I'm more amazed that the paper that supposedly reveals these candidates is difficult (impossible?) to find. As always, ALL the questions are fascinating!
12:00 one obvious way for long range communication in space is lasers. Its an hot topic for communicating with the moon and mars. Much easier to make an laser more directional so less power and smaller receivers are needed.
That was a perfect answer to the would-be Mars colonist. It's ok to dream of course, but often the obsession with living there tends to cause people to lose sight of how fantastic it will be to get there and explore - and all that means for humanity.
Hey, here's a thought: We have a lot of metal in our bodies. Calcium, sodium, magnesium, etc... Mostly they exist as ions, or as compounds in organic molecules, but wouldn't it be AWESOME if there were an alien race that had the calcium in their bodies form calcium metal, rather than an organic compound, such as bone? They would have naturally occurring metal augmenting their body structure! Maybe it could even form into naturally occurring weapons... Think of antlers, or horns. These things are usually made out of proteins, such as keratin. But if there were an alien race with metal bones, perhaps they might also have 'bony' extrusions, which are analogous to horns, but are made of metal and are sharp!!
[Cait], though [Remus] resonates a lot too for me! Love to see Q&A back! A question from me. What are astronauts breathing while onboard of a spaceship, space station or inside a space suite? What is the air composition and the pressure? Is there a standard or are these different variations? I tried to search but the results seem to vary based on my query and are vague in general. And thanks @frasercain for the awesome job you're doing!
Hey Fraser, how are they going to keep that starshade exactly on the line-of-sight between the star and the telescope? There will be different orbital motions tending to drag the starshade off that line. Moreover, there will be light pressure from the sun. I'm suspicious about the whole starshade project for those reasons. My boondoggle alarm is ringing.
You mentioned the LIGO stations being sensitive to the delay as the wave crosses their locations. Would it make sense to set up a third and fourth receiver, with a very accurate time known at each, and use the temporal difference to locate the source in three dimensions like the Antarctic array does with neutrino sources?
LIGO only has the two detectors so they can use the amplitude and delay to narrow down where the source is to two regions in the sky. (The amplitude is affected by how the plane of the detector arms are oriented to the source of the gravitational waves, so they also give information where the source is.) VIRGO and KAGRA are two new detectors, in Italy and Japan, that started working collaboratively with the two LIGO detectors, in 2017 and 2020 respectively. This means that the Gravitational Wave events detected since about August 2017 have been able to be triangulated to a single "small" patch of the sky. For example the binary neutron star merger, GW170817, was able to be narrowed down to a patch of sky 5 times the diameter of the moon in width and 25 times the diameter of the moon in length using the gravitational wave data, for an idea of why i put small in inverted commas. Link to the scientific paper by LIGO & VIRGO on GW170817 for reference: doi.org/10.1103%2FPhysRevLett.119.161101
@@DrDeuteron With two the best you could get is an angle describing a cone. With three or more we get a vector. It turns out detectors are installed in the US (LA&WA) and also in Germany, Italy and Japan with India looking to join the party too. Thank you for prompting me to dig a little further.
Great format/video and podcasts, keep up the great work. So here is a question for you. People debate on if the universe is infinite or finite. My Question is that IF the universe is finite, but it is a sphere that wraps around, wouldn't light that approached you make you think it is infinite due to the large redshifts? In other words, the light would pass you by, it would be redshifted, and then the second time it passes you by (assuming you live for millennia), wouldn't it be so redshifted that you would believe it's a different beam of light? Thanks.
The key to knowing we're in a finite universe that's smaller than the observable universe would be to see structures mirrored on opposite sides of the sky. If you see a giant galaxy cluster in one direction and then a mirror image of it in the opposte direction, then you know it's the same thing, seen from different angles.
11:00 - accelerating gravity masses the size of Jupiter can be detected with ligo - search "using gravity waves to detect space ships" 11:10 - the reason we search in EM is because of the fundimental forces of the universe - gravity, em, strong + weak nuclear forces - nuclear forces are too short range, gravity is gravity waves and requires stupid energy expendenture to create, leaving EM photons or other particles. Out of particles only neutrinos are stable enough and non-interactive enough to be used to transmit information .... but they are so non-interactive that a literal supernova results in only a few 22:00 "dozens of light years" - don't you mean mega-parsecs? or some other bigger-than-galaxy-cluster distance?
Am I the only person that like to pause change videos and then come back so it plays another ad just so hopefully Fraser gets a little extra ad revenue I can’t be the only one……right? Or am I just crazy!?!?!
Janus- Study trades Electrical, Plumbing, welding, and never forget heating and air conditioning systems. Even if you do not meet the physical requirements to go to Mars you will have a fantastic well-paying job on Earth! A master Tradesman is a hard thing to find.
Regarding the constraints on sizes of telescopes because of the limited space in the launch vehicle that's where spacex's starship will come in handy you'll be able to launch much bigger telescopes if it does actually come on line
Here is a hypothesis for you. The red shift we see from objects millions or billions of light years away, is not due to motion. It is due to photons interacting with virtual electrons and positrons that pop into space time for an instant before canceling each other.
I hadn't thought about but I suspect you would never find a planet with a thick Hydrogen atmosphere near a star. The first thing a solar wind does is blow away the lightest elements from nearby planets. On the other hand, rogue planets would naturally be storehouses for such gasses, kept there by gravity. As for liquid oceans, how thick would that atmosphere have to be to keep that ocean liquid?
Helluva Video !!! I love how you switched to Star Trek worlds .... you should do Farscape or Stargate worlds next....or maybe....Babylon 5 worlds....so many to choose from !!! Again, a really awesome video!!! Thank you !!!
Hi Frazer, you lost me with the free floating Hicyan world with liquid water. You said a thick H2 atmosphere could make a platnet surface with liquid water up to 3 AU from a star. However an unbound planet would likely be 1000s of AUs from a star so how could it have unfrozen liquid water oceans ?
06:00 Basically ligo and it's sister gravitational observatories are deaf to the ultra low frequencies of the background gravitational noise. Much like we humans are deaf to the really low subsonics. Ligo is in effect sensitive only to the "ultrasonic" chirps of the small black holes & neutron stars collisions while being oblivious to the "subsonic" noise of the gravitronic background. The reason why ligo & sisters are deaf to the background noise is because they're NOT big enough to detect them. If they try building a gravitational observatory thats big enough to detect the gravitational subsonics on Earth, ye get problems with noise contamination from Earth itself. Earth is constantly full of vibrations and noise. It will be like trying to listen to a whisper from a mile away while someone behind ya is going crazy with a jackhammer. Second issue is finding a geologically stable area that's big enough to accomodate the many scores of miles you'll need to build a background gravitational observatory. Good luck finding and acquiring that! Tis much more easier to just build four satellites and send them out to space and have them align themselves to precise coordinates relative to themselves and the parking space (most likely at an Earth/Sun Lagrange point). In space ye have the additional flexibility of adjusting the size of the array so it can be more sensitive to different frequencies as needed.
Now I can't stop wondering about the possibility of a rogue planet/brown dwarf being near enough to Earth for us to eventually visit (or vice versa, in that unlikely chance it'd harbor intelligent life).
You can just play Starfield on Game Pass unless you're on PlayStation. Btw I never got into Skyrim but I've been very addicted to Starfield. People compare it to Starfield too much, as they are very different experiences, but I think you will like Starfield if you liked NMS. And you can build your own spaceship, which is very fun.
Nice, but you need to explain the CFC thing better Sir Fraser: CFC were used in refrigerators, but also aerosols, and made a hole in our planet's ozone layer. Global warming due to the contrast in temperatures they think is causing an ozone hole again unfortunately, this time primarily over the Northern Hemisphere.
(Cait) If a planet is tidally locked, wouldn't its core be even more likely to be tidally locked? And, wouldn't that screw with plate tectonics? As well as the EM field?
Dear sir, green forest background was really good. Please make videos like before if possible. Amazing videos, I hope your channel rises to millions subscriber.
Why is hydrogen a greenhouse gas? I thought greenhouse gases were mostly 3 atoms or more, to allow flexing or twisting. H2 doesn't do that, as 2 molecules are straight, by default. Not many options for movement. About 1:26
Question: if the Edwin Hubble Space Telescope is referred to as Hubble, why isn't the James Webb Space Telescope called Webb? Thank you for keeping my mind expanding.
Venus would have a temperature of 40°C without a dense 91 bar atmosphere, but Venus’s true temperature is likely closer to 480°C predicted by the ideal gas law, although the super-critical quasi-liquid nature of the Venusian atmosphere may somewhat compromise its accuracy at low altitudes. Denser atmospheres extend into space further, that is they are “taller” and but should not have a significantly different thermal gradient or “lapse rate”.
I can see how tidal forces could provoke widespread volcanic activity, on a planet that's being ejected from it's system. With enough planetary ice, it might create temporary oceans.
Hello Fraser, just a follow up question about these Hycean planets. When you say they have a rich dense hydrogen atmosphere, does that mean that this atmosphere can be set on fire/explode? I'm guessing not, since an asteroid would set it on fire because of friction. Also..Crabpeople Also, [Cheleb] because of no mans sky
This may sound like a dumb question but if it had water on the planet would not there be some kind of hydrologic cycle? Would that cause thunderstorms and lightning? If so would that cause parts of the atmosphere to explode? How long could that last before the atmosphere just burns out?
Betazed. All Hail Mary! Now THAT was hard to put down, as was the Martian. Recommend "The first 15 lives of Harry August". Can't remember any crab aliens in Sci-Fi (Starship Troopers?), although Spiders have exoskeletons (Children of Time).
They may have found a way to manipulate mass in a very small amount but with a huge density that could make gravitational waves and use that to communicate! (?)
The easiest particle we can move around is the electron. While it might be fun to see if I can play music through the LIGO detectors I doubt it would carry well, even with insane voltages and huge spheres miles apart.
Can a red giant star currently burning helium with a black hole or other compact binary partner "fizzle out" due to the compact object tidally stripping away so much of its envelope/mass that the core pressure is no longer high enough to permit helium fusion? What would such an object look like?
Hydrogen isn't a greenhouse gas; it's an indirect greenhouse gas. That wouldn't explain a warmer climate on an exoplanet. Perhaps radioactive decay and associated volcanism, or some unexplained tidal force, or relatively recent major impact, but not hydrogen.
Cait: I would think that with repeated observations of a planet, it would potentially be possible to detect atmospheric changes that strongly suggest volcanism / plate tectonics. Using earth as an example, it would be possible to see immense increases in volcanic gases such as sulphur compounds and CO2 when an event such as the PETM occurred. Recent studies suggest the PETM could have been caused by massive eruptions (potentially over several million years) of the North Atlantic Large Igneous Province, and possibly a second igneous province too. I don’t know if we have enough data to determine if it’s possible to have volcanism on a planet but an absence of plate tectonics, my hunch would be that the two go hand in glove. In our own solar system Io would be worth studying to see if there are any kinds of tectonic processes occurring, although the volcanism there is believed to be largely driven by the immense gravity and magnetic field of Jupiter. Closer observations would be great to try and determine with certainty. Thanks for a great episode as always Fraser!
Everyone always says Mars sucks! But for people like me that are over sensitive to the sun. I literally can't go outside in the Sun Very long.. I get bad headaches, skin gets irritated etc. I hide in a Dark Place as much as possible. So for me... Being a Mars would be awesome! Plus if Elon Musk wants to send a Million people to Mars... they will need everyone including a plumber, Cooks, Botanist would be a good field. Engineering can never go wrong. They would even need Security, caretakers, Drs, Miners, the list goes on. Just make sure you are the best of said field and also be very smart. Learn EVERYTHING you can. Just my plan to get on the list 🙂 Also Fraser do you live in Vancouver, Canada? I think I heard you say that.. but wasn't sure. Let me know.
I think the question about JWST giving wrong results about intelligent life on Earth is just a snide remark like I would make about the existence of intelligent life on Earth.
On the topic of convergent evolution, didn't Gregg Bear write a book series which involved intelligent crabs on Titan? I don't remember the title.. great show, cheers
We can now finally answer: does CO2 cool or warm the earth? Strictly speaking, radiatively, it can do neither because it is utterly incapable of changing the energy flux. Because some may argue that because the partial pressure of the atmosphere increases due to the addition of carbon, releasing CO2 increases the density of the atmosphere and could produce a tiny amount of warming. It turns out that because hydrocarbons contain a substantial amount of hydrogen, and hydrogen forms water when combusted, the net result of hydrocarbon combustion is a reduction in atmospheric pressure and hence temperature, although the magnitude of this effect is extremely small. How ironic is it that how three century long voracious appetite for carbon has cooled our climate by a few microkelvins?
I think looking in the habitable zone only makes sense if we are looking for a planet to colonize. Once we stop thinking all life is the same this pretty much opens up all planets to 'life' doesn't it?
You didn't address the part of the first question about a hydrogen atmosphere, which could never turn into snow simply because of the physical attributes of hydrogen and helium that make it impossible for them to freeze out of an atmosphere, although metallic hydrogen can exist under very high pressure.
Here is another question for you on your favorite topic: LAGRANGE POINTS!!! Why are their (5) LaGrange points between a two body problem, and not 6, or 8, or 50, or a continuous function of gravitational points that vary with location? We know that nothing in space is "truly" a stable point. Could we split the highly unstable 1,2,3 LaGrange points into both an "inward or outward" area (L1-out, L1-in), or multiple gravitational areas effectively creating 8+ Lagrange points? Why five? (hopefully it's not because of the numbers of fingers we have on one hand).
Quantum entanglement, Einstein's "Spooky action at a distance"--- Is an excellent POSSIBLE example of practical interstellar communication. Instant communication across light year distances, rather than YEARS for radio waves. But of course WE haven't been able to do that or listen in with OUR degree of technology YET. Check out HUT (Holographic Universe Theory) Physics. This is possible under this theory, along with instant "Space Jumps" for FTL starships. HUT is supported with lots of evidence and explains a lot of mysteries of the Standard Model, like observer effect, Quantum Entanglement, etc.--- HUT may be the Physics of the future. Alas, many Mainstream Physicists haven't got the "Imagination" to consider HUT. "Imagination", according to Einstein, is one of the most important abilities a Physicist needs to create new theories.
Hydrogen is a two atom molecule definetly not a 'green house gas'. Are you talking of methane , carbon tetra hydrogen? why, because the vibration motion between the two atoms does not produce a Dipol moment, which interacts with resonant photons. The H2 molecule is symmetric to perfection. Like O2, N2.
OMG Fraser...im 51 now and just had to get my first pair of reading glasses too (Workstation ones meant for PC use etc and reading all in one...world of difference but ya getting older sucks specially for us Gen Xers (first aging video game generation) lol.
Question - in the big universe, trillions of times further than what we can ever see - could there be vast swathes of annihilated nothingness then antimatter galaxies ?
X-rays are probably used by advanced civilisations for high capacity interstellar communications. Sadly for us, they're a bit hard to focus in a big aperture.
I wanna ask if you could get a cyclical universe from the stretch of space time its self? Like what if space time is elastic like a rubber band and will reach a point where it can no longer stretch and will snap back instead of ripping.
@@xenolion339 seems like most of the theories i look at are gravity based. I mean something that gives the property of elasticity like a rubber band to the fabric of space time
So happy the Q&As are back after the summer break!
31:52 "If you went to some random exoplanet, anywhere in the world..."
Thank you. You just made my day.🤣
Great video Fraser. People have to remember that we are generally looking at short orbits with the transit method...longer orbit worlds will take more time to validate. A world exactly like earth orbit wise would take 2 to 3 years just to validate.
2-3 years just to validate its existence as well. If there was anything interesting, like a biosignature, expect confirmation for that to take even longer.
@@urphakeandgey6308 That's why I eat tacos in the morning and evening. Make it easier for the aliens to see the methane.
I love how you handled the question from the hopeful Mars colonist. Realist, honest, and being ready for unknown future opportunities. I also liked your KISS attitude for future space telescopes. Pragmatism FTW!
I took a bunch of astronomy + physics in school, so it's not like I've never been exposed to any of this, but I've been listening to a lot of space stuff like this channel on yt this yr and just the scale of everything in space from temps, to dist, to sizes, to time scales is so absolutely mind boggling and utterly alien to our daily existence
Cheers Fraser this made my day at work listening to space news while working a boring factory job 🙃
Same here… different job though
Thank you *so* much for answering my question about plate tectonics and exoplanets, Fraser. I stayed up late at night (Lisbon time) to catch the Q&A. I was only able to barely stay awake to ask my question and didn’t watch the rest of the show. I was anxiously waiting for the video to go live 😊. (I realize the patreon feed has the original video but I usually don’t look at it). Anyway, thank you so much. You’re my fav youtuber!
I find rogue plants super interesting. They are worlds we consider lost. Perhaps life can thrive in an isolated world. Scary thought to even imagine what the skyline actually would look like.
Likely wouldn't have a skyline but instead an extensive underground network utilizing geothermal energy
How does this channel not have more subscribers? I find the content fascinating and I particularly enjoy the Q&A videos. It must take a great deal of time and effort to research and create such an impressive volume of videos. You definitely deserve way more subs Fraser! Keep up the great work 👍
I suggested this on a Dr Becky video, why argue about how to pronounce Hycean, when we have a perfect replacement in Wet Giant. You know, Gas Giant, Ice Giant, and now Wet Giant. Other options; moist giant, damp giant, soggy giant. If we are sticking with Hycean, then surely it is pronounced like Ocean, but instead of Oh its Hi.
Soggy diaper
Janus:You have such a rich mind to imagine so many different scenarios with planets and suns. That is amazing!
I really appreciate how quickly you jump in to the meat of your contact instead of advertisements, such
Here’s a question you’ve probably answered 1 million times but I am ignorant and don’t know… How was the speed limit of light determined? What I mean is how does Einstein/others know that things can’t go faster?
It's an amazing story. An astronomer was looking at how long it took Io to go once around Jupiter and they noticed that over the course of the year that time changed and they realized it was because Earth was getting closer and farther to Jupiter and they're able to measure the difference and calculate the speed of light
@@frasercain hey cool story! What I meant was what is preventing the objects from going faster than the speed of light- chat Gpt told me that it was that you needed an infinite amount of energy to go that fast
Even though I always watch your videos, I don’t usually like and subscribe to anything just because they pop up in my feed on my watch to the end… But I’ll subscribe to you right now, just for being awesome!
The question about plate tectonics was very good, as was your answer. I think it's possibly a prerequisite to life on this planet and could potentially point towards other life. But as you said, it is difficult to detect.
To have plate tectonics will need liquid water. Venus has no liquid water. That results in harder and brittle rock on the surface.
In regards to Betelgeuse going off, how would we receive neutrinos before visible light if nothing can exceed the speed of light? Does it release neutrinos just before it goes supernova?
The neutrinos can escape the explosion immediately, while the light is tangled up in the infalling material. So, neutrinos first, then radiation.
And will I develop Superhuman Powers@@frasercain?
Just me preferably, no one else... cos that'd defeat the object, and I'd just be left feeling "Super Normal?"
@@sebastianwrites “when every one’s super, no one will be”
Nothing goes faster than light _in a vacuum._ Light goes slower if it isn’t in a vacuum.
If the core explodes, the light from that has to penetrate several light minutes worth of not vacuum before it gets out into free space.
If the phrase "look similar to Earth creatures" means anything remotely coherent to you (not you specifically, Fraser, the generic you), you need to see more Earth creatures! Our biosphere has so much diversity and so many weird looking and weird acting organisms that we hardly even need to imagine aliens-just looking around ourselves should be enough to make us marvel at all the weird stuff! Evolution is an unguided exploration of the space of all possible life forms, of which we get to see one slice here, and other slices will probably look both similar and different.
Thank you for taking my question yesterday. Really made my day.
Andoria - question about Hycean worlds.
Vulcan - question about gravitational waves detectors.
Risa - question about non-radio communication and the Fermi paradox.
Aeturen - question about JWT looking for earth analog exoplanets.
Hmm, difficult choice… can I say AnCaSEn
Edit: As it goes along, I am adding more parts to the name.
They’re ALL my favorite 😅
Andoria. And a question: Why is the starshade petal shaped like a flower and not simply round?
I loved your reply to the young person interested in going to Mars. people need to understand that it’s gonna take a huge industrial effort to make life work on Mars. So we need all kinds of people with all kinds of skills and attitudes and interests.
I have a question for you. I would love to hear more about how you got into this kind of work. What did you study in school? Have you worked on any of the space missions previously?
Risa. I am amazed that there may be 70 candidates for instances of intelligent communications. I'm more amazed that the paper that supposedly reveals these candidates is difficult (impossible?) to find. As always, ALL the questions are fascinating!
Not candidates, but ideas for types of technosignature. So, nuclear war, radio signals, etc.
@@frasercain Mahalo, Fraser, for clearing that up for me! Aloha!
12:32 I completely misread this question. At first I thought this was a joke about humans being unintelligent.
Oh, I think it was a joke, I just answered it straight.
12:00 one obvious way for long range communication in space is lasers. Its an hot topic for communicating with the moon and mars. Much easier to make an laser more directional so less power and smaller receivers are needed.
That was a perfect answer to the would-be Mars colonist. It's ok to dream of course, but often the obsession with living there tends to cause people to lose sight of how fantastic it will be to get there and explore - and all that means for humanity.
Exactly what i have speculared about such worlds. Tidal heating and radioactive core/mantel.
Hey, here's a thought:
We have a lot of metal in our bodies. Calcium, sodium, magnesium, etc... Mostly they exist as ions, or as compounds in organic molecules, but wouldn't it be AWESOME if there were an alien race that had the calcium in their bodies form calcium metal, rather than an organic compound, such as bone? They would have naturally occurring metal augmenting their body structure! Maybe it could even form into naturally occurring weapons... Think of antlers, or horns. These things are usually made out of proteins, such as keratin. But if there were an alien race with metal bones, perhaps they might also have 'bony' extrusions, which are analogous to horns, but are made of metal and are sharp!!
[Cait], though [Remus] resonates a lot too for me!
Love to see Q&A back!
A question from me. What are astronauts breathing while onboard of a spaceship, space station or inside a space suite? What is the air composition and the pressure? Is there a standard or are these different variations?
I tried to search but the results seem to vary based on my query and are vague in general.
And thanks @frasercain for the awesome job you're doing!
Vendikar, because I've been wondering about this myself.
Hey Fraser, how are they going to keep that starshade exactly on the line-of-sight between the star and the telescope? There will be different orbital motions tending to drag the starshade off that line. Moreover, there will be light pressure from the sun. I'm suspicious about the whole starshade project for those reasons. My boondoggle alarm is ringing.
Aeturen: I suspect you missed the joke.
“Beam me up, Scotty; there’s no intelligent life down here.”
You mentioned the LIGO stations being sensitive to the delay as the wave crosses their locations. Would it make sense to set up a third and fourth receiver, with a very accurate time known at each, and use the temporal difference to locate the source in three dimensions like the Antarctic array does with neutrino sources?
LIGO only has the two detectors so they can use the amplitude and delay to narrow down where the source is to two regions in the sky. (The amplitude is affected by how the plane of the detector arms are oriented to the source of the gravitational waves, so they also give information where the source is.)
VIRGO and KAGRA are two new detectors, in Italy and Japan, that started working collaboratively with the two LIGO detectors, in 2017 and 2020 respectively. This means that the Gravitational Wave events detected since about August 2017 have been able to be triangulated to a single "small" patch of the sky. For example the binary neutron star merger, GW170817, was able to be narrowed down to a patch of sky 5 times the diameter of the moon in width and 25 times the diameter of the moon in length using the gravitational wave data, for an idea of why i put small in inverted commas.
Link to the scientific paper by LIGO & VIRGO on GW170817 for reference: doi.org/10.1103%2FPhysRevLett.119.161101
I think they use Virgo to do exactly that. It’s a little different from neutrinos since they are polarized, and that depends on their orientation
@@DrDeuteron With two the best you could get is an angle describing a cone. With three or more we get a vector. It turns out detectors are installed in the US (LA&WA) and also in Germany, Italy and Japan with India looking to join the party too. Thank you for prompting me to dig a little further.
Great vid 👍👍👍
Great format/video and podcasts, keep up the great work. So here is a question for you. People debate on if the universe is infinite or finite. My Question is that IF the universe is finite, but it is a sphere that wraps around, wouldn't light that approached you make you think it is infinite due to the large redshifts? In other words, the light would pass you by, it would be redshifted, and then the second time it passes you by (assuming you live for millennia), wouldn't it be so redshifted that you would believe it's a different beam of light? Thanks.
The key to knowing we're in a finite universe that's smaller than the observable universe would be to see structures mirrored on opposite sides of the sky. If you see a giant galaxy cluster in one direction and then a mirror image of it in the opposte direction, then you know it's the same thing, seen from different angles.
"Andoria" gets my vote.
Nice
11:00 - accelerating gravity masses the size of Jupiter can be detected with ligo - search "using gravity waves to detect space ships"
11:10 - the reason we search in EM is because of the fundimental forces of the universe - gravity, em, strong + weak nuclear forces - nuclear forces are too short range, gravity is gravity waves and requires stupid energy expendenture to create, leaving EM photons or other particles. Out of particles only neutrinos are stable enough and non-interactive enough to be used to transmit information .... but they are so non-interactive that a literal supernova results in only a few
22:00 "dozens of light years" - don't you mean mega-parsecs? or some other bigger-than-galaxy-cluster distance?
Aeturen : Excellent video!
Am I the only person that like to pause change videos and then come back so it plays another ad just so hopefully Fraser gets a little extra ad revenue I can’t be the only one……right? Or am I just crazy!?!?!
Thanks for the great content.
Great channel. Love the Seattle background example.
Risa - great Answer, Fraser 😊 Thanks!
Janus- Study trades Electrical, Plumbing, welding, and never forget heating and air conditioning systems. Even if you do not meet the physical requirements to go to Mars you will have a fantastic well-paying job on Earth! A master Tradesman is a hard thing to find.
I really enjoy your talks Fraser.
Good tangent fraser
REMUS Don't forget to vote guys
Risa, if we can discover and utilize tachyons then we could have faster than light communication
The very best way for aliens to communicate is through black hole bowling.
Great content, Frazer! And if you are playing No Man Sky, don't bother with Starfield, it will bore you to tears
Regarding the constraints on sizes of telescopes because of the limited space in the launch vehicle that's where spacex's starship will come in handy you'll be able to launch much bigger telescopes if it does actually come on line
Here is a hypothesis for you. The red shift we see from objects millions or billions of light years away, is not due to motion. It is due to photons interacting with virtual electrons and positrons that pop into space time for an instant before canceling each other.
I hadn't thought about but I suspect you would never find a planet with a thick Hydrogen atmosphere near a star. The first thing a solar wind does is blow away the lightest elements from nearby planets. On the other hand, rogue planets would naturally be storehouses for such gasses, kept there by gravity. As for liquid oceans, how thick would that atmosphere have to be to keep that ocean liquid?
Helluva Video !!! I love how you switched to Star Trek worlds .... you should do Farscape or Stargate worlds next....or maybe....Babylon 5 worlds....so many to choose from !!! Again, a really awesome video!!! Thank you !!!
Liquid oceans on a rogue planet may be caused by volcanic action on the planet. Nice work. 🍔🍗🍟🍦🌭
Hi Frazer, you lost me with the free floating Hicyan world with liquid water. You said a thick H2 atmosphere could make a platnet surface with liquid water up to 3 AU from a star. However an unbound planet would likely be 1000s of AUs from a star so how could it have unfrozen liquid water oceans ?
Cait: ‘Plate Techtonics on that star !’
Really Fraser ? - I think you meant the planet..
Yes, of course.
06:00 Basically ligo and it's sister gravitational observatories are deaf to the ultra low frequencies of the background gravitational noise. Much like we humans are deaf to the really low subsonics. Ligo is in effect sensitive only to the "ultrasonic" chirps of the small black holes & neutron stars collisions while being oblivious to the "subsonic" noise of the gravitronic background.
The reason why ligo & sisters are deaf to the background noise is because they're NOT big enough to detect them.
If they try building a gravitational observatory thats big enough to detect the gravitational subsonics on Earth, ye get problems with noise contamination from Earth itself. Earth is constantly full of vibrations and noise. It will be like trying to listen to a whisper from a mile away while someone behind ya is going crazy with a jackhammer. Second issue is finding a geologically stable area that's big enough to accomodate the many scores of miles you'll need to build a background gravitational observatory. Good luck finding and acquiring that!
Tis much more easier to just build four satellites and send them out to space and have them align themselves to precise coordinates relative to themselves and the parking space (most likely at an Earth/Sun Lagrange point). In space ye have the additional flexibility of adjusting the size of the array so it can be more sensitive to different frequencies as needed.
Now I can't stop wondering about the possibility of a rogue planet/brown dwarf being near enough to Earth for us to eventually visit (or vice versa, in that unlikely chance it'd harbor intelligent life).
You can just play Starfield on Game Pass unless you're on PlayStation. Btw I never got into Skyrim but I've been very addicted to Starfield. People compare it to Starfield too much, as they are very different experiences, but I think you will like Starfield if you liked NMS. And you can build your own spaceship, which is very fun.
Does SETI account for redshift? How far down do scopes go? 🙂
Nice, but you need to explain the CFC thing better Sir Fraser:
CFC were used in refrigerators, but also aerosols, and made a hole in our planet's ozone layer.
Global warming due to the contrast in temperatures they think is causing an ozone hole again unfortunately, this time primarily over the Northern Hemisphere.
(Cait) If a planet is tidally locked, wouldn't its core be even more likely to be tidally locked? And, wouldn't that screw with plate tectonics? As well as the EM field?
Have SETI tried morse code frequency? Nobody seems to be listening to our radio frequencies.
I have a question. Is Science discovery's driven by" I said it First!!" or by Pure research?
Are JWST and Hubble doing any coordinated activities while Hubble is still functional? What would be a good target?
If we took water up to the black energy, from ocean with living beings would they live in the ocean water in space?
Dear sir, green forest background was really good. Please make videos like before if possible. Amazing videos, I hope your channel rises to millions subscriber.
Why is hydrogen a greenhouse gas? I thought greenhouse gases were mostly 3 atoms or more, to allow flexing or twisting. H2 doesn't do that, as 2 molecules are straight, by default. Not many options for movement. About 1:26
Could plate tectonics be driven by the internal rotating molten core of the Earth interacting with magnetic materials in the crust?
Space always blows my mind like if betelgeuse went supernova today it we won't know until 642.5 years from today the distances are mind blowing
Of course, if it happened hundreds of years ago, we'll learn about it now.
Question: if the Edwin Hubble Space Telescope is referred to as Hubble, why isn't the James Webb Space Telescope called Webb?
Thank you for keeping my mind expanding.
Venus would have a temperature of 40°C without a dense 91 bar atmosphere, but Venus’s true temperature is likely closer to 480°C predicted by the ideal gas law, although the super-critical quasi-liquid nature of the Venusian atmosphere may somewhat compromise its accuracy at low altitudes. Denser atmospheres extend into space further, that is they are “taller” and but should not have a significantly different thermal gradient or “lapse rate”.
I can see how tidal forces could provoke widespread volcanic activity, on a planet that's being ejected from it's system. With enough planetary ice, it might create temporary oceans.
Hello Fraser, just a follow up question about these Hycean planets. When you say they have a rich dense hydrogen atmosphere, does that mean that this atmosphere can be set on fire/explode? I'm guessing not, since an asteroid would set it on fire because of friction.
Also..Crabpeople Also, [Cheleb] because of no mans sky
There will not be any significant free oxygen available to support a fire of explosion.
This may sound like a dumb question but if it had water on the planet would not there be some kind of hydrologic cycle? Would that cause thunderstorms and lightning? If so would that cause parts of the atmosphere to explode? How long could that last before the atmosphere just burns out?
There will not be any significant free oxygen on such a planet. Without the free oxygen there will be no fire.
Betazed. All Hail Mary! Now THAT was hard to put down, as was the Martian. Recommend "The first 15 lives of Harry August". Can't remember any crab aliens in Sci-Fi (Starship Troopers?), although Spiders have exoskeletons (Children of Time).
They may have found a way to manipulate mass in a very small amount but with a huge density that could make gravitational waves and use that to communicate! (?)
The easiest particle we can move around is the electron. While it might be fun to see if I can play music through the LIGO detectors I doubt it would carry well, even with insane voltages and huge spheres miles apart.
Would a third arm, in the third dimension, be usefull for ligo?
Great episode Fraser.
-interloper
Grah!
Can a red giant star currently burning helium with a black hole or other compact binary partner "fizzle out" due to the compact object tidally stripping away so much of its envelope/mass that the core pressure is no longer high enough to permit helium fusion? What would such an object look like?
Hydrogen isn't a greenhouse gas; it's an indirect greenhouse gas. That wouldn't explain a warmer climate on an exoplanet. Perhaps radioactive decay and associated volcanism, or some unexplained tidal force, or relatively recent major impact, but not hydrogen.
Cait: I would think that with repeated observations of a planet, it would potentially be possible to detect atmospheric changes that strongly suggest volcanism / plate tectonics. Using earth as an example, it would be possible to see immense increases in volcanic gases such as sulphur compounds and CO2 when an event such as the PETM occurred. Recent studies suggest the PETM could have been caused by massive eruptions (potentially over several million years) of the North Atlantic Large Igneous Province, and possibly a second igneous province too. I don’t know if we have enough data to determine if it’s possible to have volcanism on a planet but an absence of plate tectonics, my hunch would be that the two go hand in glove. In our own solar system Io would be worth studying to see if there are any kinds of tectonic processes occurring, although the volcanism there is believed to be largely driven by the immense gravity and magnetic field of Jupiter. Closer observations would be great to try and determine with certainty. Thanks for a great episode as always Fraser!
Everyone always says Mars sucks! But for people like me that are over sensitive to the sun. I literally can't go outside in the Sun Very long.. I get bad headaches, skin gets irritated etc. I hide in a Dark Place as much as possible. So for me... Being a Mars would be awesome! Plus if Elon Musk wants to send a Million people to Mars... they will need everyone including a plumber, Cooks, Botanist would be a good field. Engineering can never go wrong. They would even need Security, caretakers, Drs, Miners, the list goes on. Just make sure you are the best of said field and also be very smart. Learn EVERYTHING you can. Just my plan to get on the list 🙂
Also Fraser do you live in Vancouver, Canada? I think I heard you say that.. but wasn't sure. Let me know.
I grew up in Vancouver, but now I live on the Island.
I think the question about JWST giving wrong results about intelligent life on Earth is just a snide remark like I would make about the existence of intelligent life on Earth.
Hydrocean was right there.
On the topic of convergent evolution, didn't Gregg Bear write a book series which involved intelligent crabs on Titan? I don't remember the title.. great show, cheers
We can now finally answer: does CO2 cool or warm the earth? Strictly speaking, radiatively, it can do neither because it is utterly incapable of changing the energy flux. Because some may argue that because the partial pressure of the atmosphere increases due to the addition of carbon, releasing CO2 increases the density of the atmosphere and could produce a tiny amount of warming. It turns out that because hydrocarbons contain a substantial amount of hydrogen, and hydrogen forms water when combusted, the net result of hydrocarbon combustion is a reduction in atmospheric pressure and hence temperature, although the magnitude of this effect is extremely small. How ironic is it that how three century long voracious appetite for carbon has cooled our climate by a few microkelvins?
I think looking in the habitable zone only makes sense if we are looking for a planet to colonize. Once we stop thinking all life is the same this pretty much opens up all planets to 'life' doesn't it?
Very interesting. Thank you ❤
Mass exceeding a certain point is probably how.
We should ask: “What is your favorite TechnoSignature.” Radio? Gravity waves? Salted suns? Pollution?
Already found a potential salted sun, The star SMSS J200322.54-114203.3.
You didn't address the part of the first question about a hydrogen atmosphere, which could never turn into snow simply because of the physical attributes of hydrogen and helium that make it impossible for them to freeze out of an atmosphere, although metallic hydrogen can exist under very high pressure.
Make it in 2 pieces, 2 launches and assemble it in space. But then we would need another launch to put in position.
Here is another question for you on your favorite topic: LAGRANGE POINTS!!! Why are their (5) LaGrange points between a two body problem, and not 6, or 8, or 50, or a continuous function of gravitational points that vary with location? We know that nothing in space is "truly" a stable point. Could we split the highly unstable 1,2,3 LaGrange points into both an "inward or outward" area (L1-out, L1-in), or multiple gravitational areas effectively creating 8+ Lagrange points? Why five? (hopefully it's not because of the numbers of fingers we have on one hand).
Quantum entanglement, Einstein's "Spooky action at a distance"--- Is an excellent POSSIBLE example of practical interstellar communication. Instant communication across light year distances, rather than YEARS for radio waves. But of course WE haven't been able to do that or listen in with OUR degree of technology YET. Check out HUT (Holographic Universe Theory) Physics. This is possible under this theory, along with instant "Space Jumps" for FTL starships. HUT is supported with lots of evidence and explains a lot of mysteries of the Standard Model, like observer effect, Quantum Entanglement, etc.--- HUT may be the Physics of the future. Alas, many Mainstream Physicists haven't got the "Imagination" to consider HUT. "Imagination", according to Einstein, is one of the most important abilities a Physicist needs to create new theories.
Hydrogen is a two atom molecule definetly not a 'green house gas'.
Are you talking of methane , carbon tetra hydrogen?
why, because the vibration motion between the two atoms does not produce a Dipol moment, which interacts with resonant photons. The H2 molecule is symmetric to perfection.
Like O2, N2.
OMG Fraser...im 51 now and just had to get my first pair of reading glasses too (Workstation ones meant for PC use etc and reading all in one...world of difference but ya getting older sucks specially for us Gen Xers (first aging video game generation) lol.
1:10 personally, I pronounce hycean as "hi-shin"
Question - in the big universe, trillions of times further than what we can ever see - could there be vast swathes of annihilated nothingness then antimatter galaxies ?
27:49 "...plate tectonics on that star." Does Fraser know something we don't?
What about Kepler 452b?? You said we haven 't found similar earth like planet within the habitable zone.
Definitely possible
X-rays are probably used by advanced civilisations for high capacity interstellar communications. Sadly for us, they're a bit hard to focus in a big aperture.
I wanna ask if you could get a cyclical universe from the stretch of space time its self? Like what if space time is elastic like a rubber band and will reach a point where it can no longer stretch and will snap back instead of ripping.
Some people theorized this and they called it the "big bounce" theory.
@@xenolion339 seems like most of the theories i look at are gravity based. I mean something that gives the property of elasticity like a rubber band to the fabric of space time
Classically it tears at the singularity, so it’s strength is infinity