Interstellar Propulsion, Uranus-Type Exoplanets, AGI Solving Space Mysteries | Q&A 255

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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[@gravelpit5680]

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

[@sandrodunatov485]

Thanks for your clear stand on the issue of AI-generated gibberish clogging youtube with nonsensical clickbait.

[@jsalsman]

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.)

[@frasercain]

Yeah, they'll have their same momentum, but less gravity to pull against. Oops.

[@stevegilliver5104]

This is exactly what I thought at the time. I still think you do a fantastic job, Fraser 😅 Thank you.

[@D_ND_H]

@@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.

[@mknochel]

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.

[@otrondal]

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.

[@nicholashylton6857]

Brian May's doctoral thesis was about to zodiacal dust. It would be amazing if you could get him on your channel!

[@Robert-do3cd]

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.

[@meesalikeu]

wssn’t zodiacal dust a b side for the flash gordon theme song single? 😂🎉

[@hatterson]

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

[@RectalRooter]

Maths is hard

[@revmsj]

@@RectalRooterI couldn’t agree more, Doc!

[@johnycollo3114]

Good little rant against the misinformation on this platform. Excellent video mate 👍

[@zadtheinhaler]

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.

[@damdampapa]

me too. at least 5-6 times a day. I am also disappointed and angry with KZbin's non-actions.

[@battragon]

57 earths can fit inside Uranus. ^^ (Never gets old.)

[@joefresh3725]

58 if you relax

[@nicolasolton]

Urs.

[@georgespalding7640]

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.

[@deltalima6703]

Ikr?

[@NullCreativityMusic]

You don't want to find anything sub-Uranus

[@3dfxvoodoocards6]

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.

[@stevegilliver5104]

Yeah, Fraser, can we get Scotty on your show for an interview?

[@nicolasolton]

Orion project recycling of tens of thousands of hydrogen bombs is the best idea!

[@filonin2]

@@nicolasolton You'd need hundreds of thousands though for even one ship so recycling won't cut it lol.

[@kayakMike1000]

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.

[@DominikJaniec]

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...

[@lyledal]

"...the other part is that it's the word 'Uranus.'" I KNEW IT! These exoplanet folks just hate being the butt of the joke.

[@darinjohnson1725]

Isn't Uranus a gas giant?

[@kacodemonio]

@@darinjohnson1725 Yes Uranus is gassy

[@ashleyobrien4937]

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 ?..

[@unvergebeneid]

Veritas is an awesome name for a Venus mission. In Venus Veritas as they say! 😄

[@HansDunkelberg1]

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?

[@chrisvincent8123]

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.

[@brianknow9142]

I always enjoy listening to your videos while working. I always pick up an interesting tidbit.

[@agentdarkboote]

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!

[@President_Mario]

It was too cloudy for me in Texas. 😞

[@olliverklozov2789]

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.

[@agentdarkboote]

@@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.

[@olliverklozov2789]

@@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?

[@agentdarkboote]

@@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!

[@ToriMarene]

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.

[@ashleyobrien4937]

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....

[@intotron6708]

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.

[@disinclinedto-state9485]

Fraser, serious question for the question show: why are you so great?

[@frasercain]

Practice.

[@davidkatzenbach7189]

Im pretty sure plnets would move out if less mass is present to sustain their orbits

[@CeresKLee]

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.

[@brucehansensc]

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.

[@symmetrie_bruch]

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.

[@brucehansensc]

@@symmetrie_bruch Well, Channel refuse is different from "Not Interested", right?

[@symmetrie_bruch]

​@@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.

[@andrew12bravo21]

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!?

[@chris-terrell-liveactive]

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!

[@LordBitememan]

Thrilled to see you recommend Steve's channel!

[@anthonyalfredyorke1621]

Thanks Fraser for another wonderful show. PEACE AND LOVE TO EVERYONE ❤❤.

[@jsteezy80]

The way you said "UR-Anus" lol and I admit I laughed. Even harder after you said "see you laughed". Good stuff sir

[@JenniferA886]

Cheers for these vids 👍👍👍

[@oldmandoinghighkicksonlyin1368]

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.

[@tonisee2]

Thank you for many great explanations and answers - the issue with YT algorithms makes your work even more important.

[@stefanandersson7519]

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 😁

[@DominikJaniec]

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 ;)

[@erkinalp]

am sure you spell it Uran

[@DominikJaniec]

@@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 :(

[@HebaruSan]

"Aeturen" was the topic that first drew my attention to Sabine Hossenfelder's blog before she came to KZbin. I was very relieved to hear you give the same answer she did.

[@briandoe5746]

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

[@GizzyDillespee]

Hopefully we'll find a channel, so our ship can make it past the reef

[@kiosmallwood576]

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?

[@peterd9698]

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.

[@HansDunkelberg1]

You'd first build another laser array at the destination, to be able to brake with it?

[@peterd9698]

​@@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. "

[@peterd9698]

@@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.

[@HansDunkelberg1]

​@@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.

[@peterd9698]

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.

[@matthewmaughan2885]

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.

[@intotron6708]

Great idea. Do you plan to pay license fees to Larry Niven (IIRC)? 😇

[@danionescu9545]

Interesting, as usual!

[@ashleyobrien4937]

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...

[@tinahickson6352]

I so appreciate your reporting.

[@averyjeromekelly5735]

Thanku cane for the propulsion segment

[@3dfxvoodoocards6]

First manned interstellar mission ?!? What ?!? We cannot even send people to the Moon...

[@bpg5530]

We pretty much can send people to the moon. But yes interstellar is a bit overreach

[@3dfxvoodoocards6]

@@bpg5530 yes we can send people too the Moon but the chances of dying are close to 100%.

[@JAGzilla-ur3lh]

Cheleb. I am very lucky and very thankful that I discovered the KZbin 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.

[@josephboisvert8213]

Like usual Fraser…. Your insight is amazing and incredible… for a journalist .

[@TheEducat0r]

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?

[@jensphiliphohmann1876]

02:04 _They'll move, I guess, closer in ..._ No. They'll move further out.

[@alleneverhart4141]

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.

[@HansDunkelberg1]

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.

[@intotron6708]

@@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.

[@HansDunkelberg1]

​@@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.-

[@deltalima6703]

Dont bother with antimatter. Put a LHC on your rocket and just shoot the beam at earth. Does the same thing.

[@alleneverhart4141]

@@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.

[@booradley4237]

Cheleb You and Kyle need to hire a lobbyists. God bless Amurica

[@Quisique]

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?

[@leahdiston827]

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?

[@davidtatro7457]

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?

[@georgion2]

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!

[@filmcochon]

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 KZbin 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.

[@fredscallietsoundman9701]

I don't know which question to vote for, but the best answer is definitely the Uranus one.

[@CL_Hat]

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.

[@laurachapple6795]

Vendikar - that was my reaction, too. The phrase 'exo-Uranus' is just intrinsically hilarious and nobody wants to use it.

[@seanplaystoomuch]

I’m not sure if they would be considered but the American Space Museum does great work with their KZbin channel. I really feel like they’re under watched. Daily videos, most often they’re interviews with space workers

[@FlyingPhantom8]

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.

[@pgantioch8362]

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.

[@formarosastudio]

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.

[@ashleyobrien4937]

16:19 Sticking to the laws of physics, I thought Fraser would have said Fusion, not antimatter. We are a hell of a lot closer to making fusion a reality than antimatter production . Storage of antimatter is obviously dodgy, unless you make it and use it immediately, but again, tech. that we have, or nearly have. Fusion (eg. Tokamaks) are not susceptible to nuclear meltdown or some runaway explosion, if it go's wrong the process just stops so it's inherently safer. As for Delta V, functional plasma temperatures are in excess of 100 million degrees Celsius , made possible only by very powerful magnetic fields achieved with new gen. superconductors, so just speculating a bit a magnetic nozzle could be used to bleed off some of that high energy for thrust. Journey time is still going to be at least decades to the nearest stars, I can't imagine anyone would want to commit their entire lifespan to being inside a tin can to reach a "maybe". So that means stars like ours, main sequence yellow dwarfs or similar, with known planets in the habitable zone ( big big telescopes). Some form of "suspended animation" will be essential, and I personally don't think that will be all that hard to work out. Many mammals already have evolved survival tactics that mirror this goal, hibernation, torpor, antifreeze proteins in sub zero arctic fish etc. The benefits for doing this are huge, a large reduction on many resources, if the reduction in respiration is significant, like say over fifty percent, other physiological problems like microgravity's burden on the body could almost be completely mitigated. Musk would have been better off attempting this rather than sticking electrodes into monkey brains, we simply know very little about the brains architecture and functions etc. to be attempting such a lofty goal, that organ is well and truly beyond our ability to interface with, like sharing dreams and thoughts in a shared conscious network, that sort of thing, is a long way off.

[@HansDunkelberg1]

What mammals do you mean?

[@JamesCairney]

Fusion is useless, no one has been able to generate more than 2% of the energy used in creating the fusion in the first place, and there is no way to harvest that energy yet. So 2% return on energy used and that 2% can not be harvested yet, so where is this fusion breakthrough? It's been how many decades of research and still they can't get out anywhere near the energy they put in to the system. Fusion is a failure.

[@ashleyobrien4937]

@@HansDunkelberg1 well, Bears, Squirrels, Hedge hogs, Bats, and the non mammals are even more numerous...

[@HansDunkelberg1]

@@ashleyobrien4937 Squirrels don't hibernate. A squirrel stores food underground and lives off it in the winter.

[@BalrogsLair]

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.

[@frasercain]

Yeah, same momentum, less gravity, orbit expands

[@dbullhorse]

For small KZbinrs, 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.

[@tripzero0]

Question: have we actually measured Hawking Radiation?

[@deltalima6703]

Answer: no

[@TheOttomann64]

You are out there and about Uranus :) Greetings from Denmark! I like how we all talk...Canadians are cute ;)

[@josephegwabor120]

Thanks

[@jasonsinn9237]

15:53 alright you got me 😅

[@Michel613]

I liked Vulcan best. Thanks.

[@Raz.C]

Hi Fraser Minor correction - Anti Matter (as well as fission and fusion) would be useless as a method of propulsion through space. They'd be great at generating power for a spacecraft, much the same way as nuclear reactors do on Nuclear Aircraft Carriers and Submarines. However, they don't generate any motive force. Anti matter, nuclear fission and nuclear fusion will react to release a LOT of energy. In space, this energy is mainly radiation (nb - Light is a form of radiation from the EM spectrum. So too is heat). If you detonate a nuke in space, you'll get a LOT of light, a LOT of heat and a LOT of ionising radiation. Unfortunately, none of these can move a spacecraft through space. At best, they can power the ship, providing it with the electrical energy necessary to utilise Ion/ Plasma engines, as well as the heat needed for Thermal Nuclear Propulsion. Regardless of what method of propulsion you choose, you'll find that Newton is still the master of propulsion; if you want to move while in space, you HAVE to shoot something out the back of your craft. Conventional rockets do this by combusting the fuel and shooting the exhaust gases out the back. Anti matter, fission and fusion don't produce gases, so there's nothing to shoot out the back of the engines, except for light, heat and ionising radiation (technically, alpha and beta radiation are particles) and none of these products have enough mass to move a spacecraft. No, anti matter, fission and fusion are quite useless as a means of propulsion. They are useful in powering a spacecraft (again, the same way a nuclear reactor powers a nuclear submarine, but doesn't actually _move_ the sub. Instead, it generates the power which powers the engines), but they'll never be able to directly move a craft through space.

[@frasercain]

They heat up a propellant, like hydrogen and blast it out the back. Photons also produce pressure

[@RectalRooter]

Well thought out and explained comment. Didn't fraser's analogy have the caveat of using some kind of collector that would " collect " something from space and then use the reactor energy to propel whatever it collected out the back of the spacecraft ?

[@Raz.C]

@@RectalRooter Yeah, I suspected that Fraser was already aware of this, but I wasn't sure, hence the comment.

[@RectalRooter]

@@Raz.C 👍 I enjoy how science gets people's minds going and thinking.

[@donaldjmccann]

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.

[@AproposOfWetSnow]

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?

[@aalhard]

Brian May's PhD thesis was zodiacal dust! Queen ftw😊

[@christianpetersen163]

Collide 2 neutron stars and ride the shockwave - you're golden.

[@FPLMikkel]

Question: What stops others for sending unauthorised commands to satellites or other things in space like telescopes etc? Are they encrypted that well?

[@erkinalp]

older ones or newer ones

[@FPLMikkel]

@@erkinalp both?

[@deltalima6703]

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.

[@FPLMikkel]

@@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?

[@ML-jl7fj]

*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!

[@Dr.Wael.Alrifai]

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?

[@CeresKLee]

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?

[@bjornfeuerbacher5514]

Notify me when proton decay has been confirmed to occur, please.

[@booradley4237]

Cheleb You already know the answer 💰

[@michaellee6489]

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!

[@FloridaMan69.]

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

[@yoseidman4166]

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

[@Yezpahr]

15:53 And because of that: Vendikar. But Cheleb is quite a pressing matter too. KZbin earns more on those automated channels because they squeeze content onto a plate a lot faster than real content creators.

[@francisschaeffer2243]

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?

[@alnewby]

Fraser, huge fan of your channel. Thank you! However, censorship is never the answer.--Al Newby

[@frasercain]

But should they be pushed by the YpuTube algorithm and encouraged to monetize?

[@alnewby]

Oh my goodness, I got a text from Fraser. I'm honored. You've made my day (smile).--Al Newby

[@RectalRooter]

@@frasercain Let the A.I generated stuff be. They are like that because the A.I data says it works. It will learn to be better at faking If we try to block or change it. Yeah know let the moron keep being a moron hahahaha

[@Carak_Oshama44th]

What video did you explain hawkin radiation? Trying to find it ? KZbin search comes up “do black holes evaporate? “video from you?

[@EinsteinsHair]

I know Science Asylum did a video on how Hawking radiation really works

[@savage5757]

13:00 Yes, we want to [learn more about Hawking radiation]

[@arjenav5968]

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?

[@acanuck1679]

Dear Fraser: During the first segment of this show, you suggested that the orbit of the Earth would draw closer to the Sun as the latter sloughs off mass. Surely the opposite would be true? After all, the momentum of the Earth in its orbital track would tend to take it further away from the Sun in this context, as the speed / momentum of the Earth would remain the same, while the gravitational force of the Sun would decrease. Please consider and confirm, thanks. Sincerely, A fellow Canuck (?)

[@frasercain]

Yup, the opposite is right.

[@mecha-sheep7674]

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.

[@scottabc72]

I think its great that your helping legitimate smaller channels. Because of the tsunami of AI produced garbage, the first casualty is going to be people trying to start new channels since even if they get suggested, I think most people are avoiding small channels since theyre probably fake nonsense

[@savetheplantet5799]

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😂

[@MelindaGreen]

Humans are never going to the stars. Even with anti-matter, the speeds involved would turn dust grains into riffle shells. Regarding SETI, one good frequency to monitor is the "water line": The frequency of the lowest hydrogen line times two, plus the lowest oxygen line. H2O. That's useful because there are no common natural lines in that region.

[@DanBennett]

Vulcan!!!

[@Scynthius137]

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.

[@aaronpettigrew9674]

Cheleb: the great risk of AI generated click-bait garbage is definitely harmful.

[@davidbeal6925]

It is a terrible situation. I actively looking for another streaming service. I wish Nebula was a little more intuitive and had a few more of my fav creators but it's getting there. For now I only watch creators that are recommended by top creators like yourself. I ignore and sometimes actively note and ignore creators recommended by YT.

[@211212112]

My interstellar money is on some type of gravity propulsion device cause: One Nothing we have or can have according to physics will work or is unlikely to be developed like antimatter. Two the (kinda) big holes in our physics is around gravity so room for new physics. Three UAPs if any are ships or probes seem to use gravitic drives.

[@aalhard]

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.

[@nbyz]

Question: So objects that enter a black hole never quite reach the event horizon from an outsider's perspective, they simply fade away over time. I've recently heard that this is also true of the stars that form stellar black holes themselves. With the right tools, would it be possible to "age" a recently-formed stellar black hole by measuring the photons from that original star thar are still being emitted?