Interstellar Propulsion, Uranus-Type Exoplanets, AGI Solving Space Mysteries | Q&A 255
ฝัง
- เผยแพร่เมื่อ 15 มิ.ย. 2024
- What engine type will the first manned interstellar mission use for propulsion? Will AI help solve any mysteries of space? Why do we have exoplanet types named after Neptune but not Uranus? Answering all these questions and more in this week's Q&A show.
Steven Baumann
/ @stevenbaumann8692
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00:00 Start
00:24 [Andoria] What will happen to the orbits of planets when the Sun expands?
03:54 [Vulcan] What can we learn from the dust in the Solar system?
08:05 [Risa] How does Venus keep its atmosphere?
12:09 [Aeturen] What does the Unruh effect mean?
14:30 [Vendikar] Why exoplanet types aren't called after Uranus?
16:14 [Remus] How will the first interstellar manned mission look like?
21:07 [Janus] What do JWST observations of organics around protostars mean?
25:26 [Cait] Are aliens limited by the transit method?
30:16 [Betazed] Will AGI help us solve the mysteries of space?
35:19 [Cheleb] Did JWST really find city lights 7 trillion miles away?
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Your closing comments are why I give $5 a month to this channel now. Its real space news in a sea of garbage and embellishments. Youre worth it, a small gesture to ensure we always have this "keeping it real" resource. Keep doing it Fraser
Thanks for your clear stand on the issue of AI-generated gibberish clogging youtube with nonsensical clickbait.
If the sun loses (central) mass, then the planets' orbits would get farther away, not closer, right? And if the central mass sheds uniformly outward, wouldn't the aggregate gravitational force still be the same? (Edit: It would, until it spreads beyond the orbit in question.)
Yeah, they'll have their same momentum, but less gravity to pull against. Oops.
This is exactly what I thought at the time. I still think you do a fantastic job, Fraser 😅 Thank you.
@@frasercain this is my first time watching one of your videos, thanks for the pin, i kept watching after that point in the video because of it, since it shows that you value being accurate.. and we all make mistakes.
For the outer planets yes they would go further out. However, I wonder about earth (if it doesn’t get consumed) and Mars, whose orbits might decay (go inward) if they experience drag from plowing through the expanded sun’s atmosphere.
You just use earths orbital elements with redusing mass over time, and integrate until 5 billion years. Then you easily get earths new distance from the sun-center.
One way you can tell the "JWST saw city lights 7 trillion miles away" story is fake is that 7 trillion miles is just under 1.2 light years which is nearly 4 times closer than our closest star
Maths is hard
@@RectalRooterI couldn’t agree more, Doc!
Brian May's doctoral thesis was about to zodiacal dust. It would be amazing if you could get him on your channel!
Dr Becky mentioned that in all the years that it's been since May was in college, and as important as the study of dust is, no one had picked up his work and finished it. It was just sitting there waiting for him.
wssn’t zodiacal dust a b side for the flash gordon theme song single? 😂🎉
Your points about AI featuring NDT or Dr. Brain Cox et al is spot on - no matter what I search for, be it astronomy/Archaeology/whatever, it is EVERYWHERE. I am honestly sick and tired of having to block all these channels.
me too. at least 5-6 times a day. I am also disappointed and angry with TH-cam's non-actions.
Good little rant against the misinformation on this platform. Excellent video mate 👍
57 earths can fit inside Uranus. ^^
(Never gets old.)
58 if you relax
Urs.
If you pronounce Uranus properly then this joke is not even funny. It's sad that our country's grammar is deteriorating thanks to texting and the internet.
Ikr?
You don't want to find anything sub-Uranus
I always enjoy listening to your videos while working. I always pick up an interesting tidbit.
Re. the difference in density of Venus atmosphere vs Earth atmosphere (part of question Risa),
is it possible that the collision with Theia resulted in Earth having less atmosphere.
It seems probable. But, I don't recall ever hearing a discussion on it.
"...the other part is that it's the word 'Uranus.'"
I KNEW IT! These exoplanet folks just hate being the butt of the joke.
Isn't Uranus a gas giant?
@@darinjohnson1725 Yes Uranus is gassy
@@kacodemonio Not if it's a miniuranus.
Its not so much that the sun runs out of useable hydrogen, the helium products build up a lot and hydrogen meet up becomes less frequent. The core looses some of its heat over time causing the core to collapse a little, at least until hydrogen meetups happen more frequently. Eventually, there's so much helium in the core, it gets in the way of enough hydrogen meetups to keep the core from collapsing under its own weight. There's a switch over to helium fusion once the core collapses enough, but this gets really really hot.
Manned interstellar missions are 100% possible, we just have to copy and use the warp technology of the Star Trak Enterprise or Voyager. I saw many Star Trak episodes and warp technology works great for interstellar and intergalactic travel.
Yeah, Fraser, can we get Scotty on your show for an interview?
Orion project recycling of tens of thousands of hydrogen bombs is the best idea!
@@nicolasolton You'd need hundreds of thousands though for even one ship so recycling won't cut it lol.
So, we are coming to the realization that there is a LOT MORE matter out there in the dark, around and way past the Oort cloud etc. I wonder what effect (if any) this will have on our models of gravitational dynamics, we hear people talk about the planet nine being out there in the dark based on the behavior of other gravitational bodies perhaps the discovery of all this extra mass out there will "fix" this ?..
I'm so glad you got to see the eclipse in Texas, I was worried for you! We went to Sherbrooke Quebec because that was the only spot on the path that consistently had a clear weather prediction. It was an amazing event!
It was too cloudy for me in Texas. 😞
why Sherbrooke? Magog had a huge party (1000's) and was closer to the center line. I did one better and went south to Ayer's Cliff - right on the line of maximum. Right on the lakeshore and only a few hundred people. Nasty traffic after.
@@olliverklozov2789 I wasn't actually in Sherbrooke, but on the center line to the east of it. Traffic was awful yeah, but I went to Kentucky for the 2017 eclipse so I was expecting it.
I didn't want to go where there were too many people since I had my mount and telescope to set up.
@@agentdarkboote Nice. I went to South Carolina in 2017 (flew into Atlanta first to visit relatives). Forgot my drivers license so rental refused - had to hire a driver. This eclipse was better - I just didn't want it to end. Still kills me that most people I know say "oh I saw 97% and that's enough". I'm like "what's 97% of zero?" Was that Jupitor a little below and west of the moon?
@@olliverklozov2789 I believe Jupiter was up and to the east, Venus was below and to the west. I wish I had had another telescope setup with me, there was a comet near Jupiter that was a little too faint to be seen by eye, but it would have been lovely to capture that as well.
Sucks to hear that you had to hire a driver! I hope it wasn't too far or expensive!
I'm glad that you are recommending other small youtubers, as you said before, with those fake-autogenerated-lying YT channels, I've stop exploring and basically do not watch unknown people...
Risa, that's an update that i hadn't heard till now, very interesting, thank you. This video is really helping me de-stress during an intense time dealing with family stuff. Thanks Fraser!
Thrilled to see you recommend Steve's channel!
Im pretty sure plnets would move out if less mass is present to sustain their orbits
about those fake news. I also saw a recommendation of a video about the thing james web saw. Was waiting on your videos to see if that actually was true or not. Am happy that I can watch this channel without worrying about fake news.
Thanks Fraser for another wonderful show. PEACE AND LOVE TO EVERYONE ❤❤.
For question two: In January 2006, a conical capsule carrying the first samples of a comet and the first pristine traces of interstellar dust ever collected landed in the Utah desert. The capsule had been dropped from NASA's Stardust spacecraft, which continued its voyage through space and became the first mission to visit two comets.
I so appreciate your reporting.
Interesting, as usual!
Oh my gosh! Been watching these videos for years and I finally got my question answered for real, and a good answer too! Thanks Fraser!
If I had to vote for a question of the week... Aeturan, maybe. Not biased 😁
Fraser, serious question for the question show: why are you so great?
Practice.
Vulcan. This was a really good Q & A episode. Every time I had a question while you were answering, you connected the dots during the answer. That's excellent communication skill! Being able to anticipate follow up questions of your audience is really nice to experience.
Cheers for these vids 👍👍👍
Thanku cane for the propulsion segment
Veritas is an awesome name for a Venus mission. In Venus Veritas as they say! 😄
You certainly mean it should run "In Venus veritas" rather than "In vino veritas" because Alcaeus, the apparent originator of the latter saying, was from Lesbos?
Thank you for many great explanations and answers - the issue with YT algorithms makes your work even more important.
Well, the building blocks for life, the amino acids, don't necessarily have to arrive from space on a asteroid, there are plenty of energy sources down here to get these reactions going to make all kinds of organic compounds not just amino acids. The Urey -Miller experiment showed that it can be done with lightning, an electric arc inside a primordial concoction of ammonia, methane, hydrogen, water, hydrogen sulfide etc. But wait, there's more ! There is geological processes with geothermal energy supplying the kick starter catalyst, even radioactive elements can have a hand in this, with complex geology forming underground lakes with wildly differing conditions some being oxidative environments others reductive environments and even the surfaces of minerals and clays acting as catalysts for reactions, the possibilities are very complex so, maybe, life is just what happens to star dust when you mix it up and cook it in certain ways....we are, just one example of what can happen with star dust....
Exactly my thoughts on that subject. The existence of those complex molecules in space is an indication on how easy this specific compounds get created, and how surprisingly stable they are. The density of atoms in the atmosphere and on the surface of a planet is very much higher than in clouds in space.
"Aeturen" was the topic that first drew my attention to Sabine Hossenfelder's blog before she came to TH-cam. I was very relieved to hear you give the same answer she did.
What's cool about finding all those complex organic compounds found all over the universe is, if you rewind the universe 's clock backwards, there was a few million years when the temp of universe sat between 32°-212°F. Could life have formed non terrestially under those conditions!?
Like usual Fraser…. Your insight is amazing and incredible… for a journalist .
Mind officially blown! This video is like a cosmic buffet of mind-bending topics. Who knew we'd be discussing interstellar propulsion and AGI cracking space mysteries all in one place?
Thanks
I don't know which question to vote for, but the best answer is definitely the Uranus one.
02:04
_They'll move, I guess, closer in ..._
No. They'll move further out.
Cheleb
You and Kyle need to hire a lobbyists. God bless Amurica
Cheleb. I am very lucky and very thankful that I discovered the TH-cam astronomy community through high quality channels like Event Horizon, Issac Arthur, and eventually Frasier Cain. I had a solid base of good channels to subscribe to before the sea of crap flooded in. Consequently, I don't really have to deal with the garbage at all. My subscription and recommendation feeds are full of the good stuff, and I know how to spot the bad.
Very interesting video. But l do have a question about the first segment. Why would the planets spiral in closer to the Sun once it has shed significant mass? Wouldn't that make its gravity weaker and encourage the planets to migrate outward?
Risa.
Related to that, how do we know that the Earth was formed in the inner solar system?
Perhaps the reason that venus and mars have so little water is that the protoplanetary disk was very dry inside of the orbit of mars. What if the collision that formed the Moon took place in the outer solar system and the Earth then spiralled in to the position it occupies now? Maybe the asteroid belt is also debris from this collision?
Remus: Wild idea. Create an antimatter generator on Mercury. Using a large solar collection there to drive the generator. Although, the ideal place might be somewhere further back where solar panels won't melt.
Great idea. Do you plan to pay license fees to Larry Niven (IIRC)? 😇
So it looks like we have a second Oort cloud. It's going to take us an extremely long time to get to interstellar speeds because acceleration is going to be very difficult going through the pebble fields.
We may already be stuck in Kessler syndrome and we just don't know it
Hopefully we'll find a channel, so our ship can make it past the reef
15:53 alright you got me 😅
It would seem that all these ever increasing complex molecules found out there like amino acids and the no doubt even more complex molecules are hinting that life is nothing more than an emergent property of matter and energy itself, all these molecules come together and with the energy supplied by stars react in very distinct and well known ways, organic chemistry and then biochemistry. I understand the nature of elements and how they react and make other compounds and so on, but it does seem very odd that this all happens in a universe that is apparently entropy driven, with everything supposedly tending toward disorder, life, it seems, is the exception to this..we are the ultimate expression of order, it's weird...
I liked Vulcan best. Thanks.
The way you said "UR-Anus" lol and I admit I laughed. Even harder after you said "see you laughed". Good stuff sir
Cheleb: You can also help a bit by mouse over the thumbnail, click the three dots that show up and selecting "Don't Recommend Channel" Its easy and YT seems to get the idea that you do not wish to be misinformed pretty quick. That said, making money on misinformation is a crime and we all are the victims.
unfortunately not, yt has no category for clickbait/garbage this is just listed under science and space. so if you do that enough you´ll see a sharp drop in actual science recommendations.
@@symmetrie_bruch Well, Channel refuse is different from "Not Interested", right?
@@brucehansensc i presume you mean "don´t recommend channel" and "not intersted" ? and yes it should be different. but i only ever use the former and still got noticably less science recomendations when i started doing that.
1. Are the gas giants just heavy 'rocky' planets with really thick atmosphere?
2. If not, what is the planet mass threshhold (or any other way) to tell if a planet is a gas or ice giant or rocky/ocean world with really thick atmosphere? Can there theoretically be a planet that is difficult to classify?
You are out there and about Uranus :)
Greetings from Denmark!
I like how we all talk...Canadians are cute ;)
I’m not sure if they would be considered but the American Space Museum does great work with their TH-cam channel. I really feel like they’re under watched. Daily videos, most often they’re interviews with space workers
If there is all this undetected dust just in the small space of the inner solar system, how does that account for the unaccounted matter? What of matter is much more common? How does that affect the “dark matter” problem?
Question, Fraser. When it comes to interstellar travel, what are the risks of a space ship encountering and colliding with space "dust?" Something like the scenario from the movie, Passengers. The space is mostly empty but even James Webb got a little battering already. At interstellar travel speeds generated by the antimatter propulsion, how small can an impacting object be and still cause catastrophic damage to the ship? What could be done to counter it? Thanks for all your great work!
A really good channel I have stumbled upon that I think you should recommend is Over The Horizon. Only have 1500 subs and have really good content with interviews discussing cool space topics. Crazy the level of content that is on that channel with nearly no viewers.
16:10 My favorite approach for interstellar travel is some sort of intelligent beamed propulsion. Eg a constant stream of tiny "starshot" like sails that can minutely adjust their trajectory over massive distances, to vaporise and push against a magnetic or electric sail on your human-scale vehicle. Of course the laser array would be in space instead of on earth. The magsail could also be used for braking at the destination. I have heard estimates of 0.2c for starshot sails.. in any case improving on that would probably be a lot easier than solving the hurdles for antimatter IMO.
You'd first build another laser array at the destination, to be able to brake with it?
@@HansDunkelberg1 google "magsail interstellar braking system" .. one promising paper was "Use of magnetic sails for advanced exploration missions" on ntrs. (I didnt read it, but google gave a quote "This would make it an ideal brake for decelerating a spacecraft from relativistic speeds and then maneuvering within the target star system.
"
@@HansDunkelberg1 Hey did my reply vanish? Its hard to tell if it is really gone or youtube being random. I gave a reference to how you can use a mag sail to brake against the interstellar medium.
@@peterd9698 I, at least, cannot see that original answer of yours. Perhaps it would make sense if you summarized its content, or the gist of the source you've given.
Search “magsail interstellar braking”. The top links seemed relevant including a nasa one. Lots of references to them being an efficient way to bleed off relativistic velocities.
35:19 [Cheleb] I think it is cool that you take the time to introduce us to other inspiring thrustworthy science youtubers.
The state of TH-cam right now make it almost impossible to search for interesting people because if by mistake I click on a video that end-up being just an IA gibberish youtube will think I was interested and will propose even more ai gibberish. I have to constantly designate "not interested" the video youtube try to propose me.
great video, I have a question if we never are able to develop warp drive could a interstellar space ship have a multi power system? such as solar sail, conventional rockets and nuclear power rockets all in one
Giggle avoidance for using Neptune as the classifier is definitely valid. I also think that Uranus is also too non-standard. If a "Uranus" like exoplanet was discovered I would assume in my head it is on it's side as well as a few other observations specific to Uranus.
While Neptune seems more like the "typical" ice-giant.
Cheleb
You already know the answer
💰
Vendikar - that was my reaction, too. The phrase 'exo-Uranus' is just intrinsically hilarious and nobody wants to use it.
Brian May's PhD thesis was zodiacal dust! Queen ftw😊
What video did you explain hawkin radiation? Trying to find it ? TH-cam search comes up “do black holes evaporate? “video from you?
I know Science Asylum did a video on how Hawking radiation really works
For small TH-camrs, I recommend Jason Kendall. He has a fantastic channel where he gives in depth lectures from simple to complex astronomical topics. Would be a great channel to shoutout.
Hi Fraser, assuming we make that antimatter engine work. Do we have a material that makes a spaceship going at 50% of light speed withstand a piece of grain in space, what kind of materials would that be?
Fraser, if all we see in the universe is the distant past, is there anybody working on a map of the universe as it is "right now"?
Thanks for your consideration! Love your channel!
Collide 2 neutron stars and ride the shockwave - you're golden.
15:45 I'm always glad that in polish language we are saying 'ooran, same for the planet and element. and also fortunately that, this sounds threateningly and nobody will laugh ;)
am sure you spell it Uran
@@erkinalp yes, but I was talking about pronunciation in english ;) as I personally "hate" english spelling, thus I was trying to write it in a commonly understood way :) to be fair, I don't know if my 'ooran, sound like "uran" in polish at all :(
13:00 Yes, we want to
[learn more about Hawking radiation]
I have a question. I very much enjoy your show. This is more of a physics question, but perhaps you will answer it. I have heard that there is a way to write Maxwell's equations such that the the two physical constants that appear in them both equal 1 and so disappear. In other words, the constants are only present as a way of scaling the equations to the size of the units that we typically use. If that is correct, is it correct in general? Is there a way to write the fundamental laws of physics such that all the fundamental constants equal 1?
Question: have we actually measured Hawking Radiation?
Answer: no
Risa - Is this encouraging news for the eventual habitation of Mars then? Perhaps it would be easier to keep an atmosphere there than we previously thought?
First manned interstellar mission ?!? What ?!? We cannot even send people to the Moon...
We pretty much can send people to the moon. But yes interstellar is a bit overreach
@@bpg5530 yes we can send people too the Moon but the chances of dying are close to 100%.
if everything emit Hawking radiation, might this tiny amount may be responsible for proton decay? An even electron decay, setting the stage for a Conformal reset as in Penrose CCC theory?
Notify me when proton decay has been confirmed to occur, please.
Cait. So many orientation issues on both ends. Conditions would be so rare or a miraculous chance. I gotta talk to someone about it now😂
15:53 And because of that: Vendikar.
But Cheleb is quite a pressing matter too. TH-cam earns more on those automated channels because they squeeze content onto a plate a lot faster than real content creators.
Cheleb was my favorite
Vulcan!!!
Hi Fraser, can you address the question why Ingenuity did not cover the top of the rotor blades with solar panels, and instead using a smaller fixed solar panel? NASA et al must have considered it, but which factors decided it? Structural integritiy? Transferring power through the axis efficiency? KISS?
QUESTION for the Question Show: is it possible that a large fraction of Earth’s water came from Theia, the impactor from the MFI? What if it somehow formed beyond the water line but then migrated inward, & even if the water vaporized during the impact, a bunch of it fell back to Earth? It might explain dry Venus & Mars (assuming he recent work shows the water depths we know of on Mars could’ve been removed by the Sun).
Best question this week: Risa.
My vote is for JANUS !
In Reply to Cheleb - I think it may be that misinformation is hard to qualify, especially with what you are saying about LLM not having the bandwidth for fact checking on a large scale. Its unfortunate, generally makes it hard to answer questions one may have about specific topics, because the search engines are cluttered with trash.
REMUS! The other problem with antimatter is that it produces energy in an unusuable form: gamma rays. Even electron-positron (the lightest ordinary matter) annihilations produce gamma rays and gamma rays, even more than x-rays, go through everything and no one knows how to focus them.
Are you mixing up gamma rays with neutrinos? Gamma rays are photons. According to NASA, photons can drive solar sails. Hence, photons must have momentum, which means that one could use them to propel rockets.
@@HansDunkelberg1 In a Matter-Antimatter annihilation the Gamma Rays photons go in two opposite directions, and randomly. To use them for propulsion you have to reflect them, so they all leave your rocket at the rear end. That reflection is the difficult part.
@@intotron6708 That could certainly mean a problem. The front side of the rocket will threaten to melt.
-An inconsistency in the original post I now see is that it won't make sense to distinguish between photons and X-rays. X-rays are just photons too, I suppose, which travel with a particular wavelength.-
Dont bother with antimatter. Put a LHC on your rocket and just shoot the beam at earth. Does the same thing.
@@HansDunkelberg1 Yes, photons of VISIBLE light can drive solar sails. Photons of gamma rays will just pass right through the sails unless the sails are made of lead. The difference is in the wavelength. Visible light has a wavelength that readily interacts with common materials. The wavelength of gamma rays is orders of magnitude smaller than visible light. I suppose one could fashion a parabolic nozzle from some sort of lead alloy and then bring the matter/antimatter together in the nozzle. The lead would absorb the energy/momentum of gamma rays traveling in the desired direction of ship-travel and the rest emitted as exhaust. If we could bring the matter/antimatter together so that gamma rays are emitted parallel to ship travel as much as possible that would enhance efficiency. Hmmm. Has some SF possibilities maybe. Making and storing antimatter is still a big problem.
I wish we were able to do things as a species that were going to benefit us in like 500 years
Question: What stops others for sending unauthorised commands to satellites or other things in space like telescopes etc? Are they encrypted that well?
older ones or newer ones
@@erkinalp both?
You need a good transmitter. A really expensive one. Like the kind nasa has. You also need someone smart enough to point it in *exactly* the right direction. A scientist would be smart enough.
@@deltalima6703 obv a bit undertaking for any private company, but let's say a foreign super power just wanted to highjack your stuff, is it feasible?
Pentastic show is always. I'm kind of divided on what I think youtube should do about the massive amounts of crap. Obviously, there could be some kind of certification process. That will also create opportunities for gaming that system. But it could help
What is the max speed that can be reached using antimatter? My back of the envelope calculation says that if you convert 100% of your mass to energy with perfect efficiency you will reach .87c.
How do I know if my question has already been asked and answered before? Is there a log of all the questions you have answered?
There isnt, sadly. You can search my channel?
@@frasercain lol are you telling us to use A.I to search your channels comments ?
Hey guys I'm new could someone please tell me why is it so difficult to send our men to the moon again when we have had boots on the ground there 6 times already did we lose the information ?
Brian May from Queen did his thesis on the Zodiacal light.
*Hint.... like blocking scam calls in the past. we have to block theese scam science videos. yu can either report. or just right click and hit , DONT RECOMEND CHANNEL. after a while YT will get it. WE HAVE TO STOP THEM. ❤❤❤ to this channel. yur the BEST.
oh and Dr. Becky. holla!
Some reason I can not explain the eclipse path in my head. I think it has to do to high point for the sun from the a person's location. The shadow looks like the orbit of the ISS. Why?
Can you talk about the Concord 70 minute solar eclipse flight?
So, how long does the red giant phase last? The animations always make it seem like minutes. But, I'm assuming it would really be much slower -- or not??
Beside anti-matter, black hole are the other kind of ultimate energy storage. Except that we can't make them until now. But I think IF we were able to produce them, they would be easier to "store" than anti-matter. And probably as dangerous or more.
16:08 I would think the similarities of N and U, the big oddity being U's reclining axis, make U a subclass of N.
Hi, suppose humanity figured out a method of intergalactic communication. What are possible ways to do time synchronization in order to communicate successfully
What would be the mechanism in what a liter star would hold on more to it's planets than a heavier one ?
How the sun loosing mass would make orbis decay
While anti-matter is expensive today, we should remember that aluminium was more expensive than gold in the 19th century. Refining and storage processes do improve! I still have some difficulty envisioning generation ships that are heading for a particular star. How can you hold the interest of successive generations for a thousand years or more to fly to an unknown place. I predict that humans would turn around in a couple of hundred years unless earth was uninhabitable.
As the Sun turns into a red giant and slowly loses mass, the orbital radius of any remaining planets will *INCREASE* (due to conservation of angular momentum); you can demonstrate this in Universe Sandbox by setting the mass of the Sun to 0.9 solar masses, and watching the planet's orbits expand out.
Yeah, same momentum, less gravity, orbit expands