Viruses from Mars, Asteroid Landing, Stars Colliding | Q&A 219

What are the risks of returning samples from Mars? What happens if you bring two stars together? Which galaxies can be seen with the naked eye? What is the system behind naming stars and exoplanets? All this and more in this week's Q&A!
00:00 Start
01:19 [Tatooine] Can we bring viruses from Mars?
07:42 [Coruscant] What is the maximum size limit for black holes?
12:03 [Hoth] What happens when two stars come together?
15:26 [Naboo] What to expect from Artemis 2?
17:32 [Kamino] What are my thoughts on Artemis 2 crew?
20:57 [Bespin] How are stars and planets named?
23:43 [Mustafar] Which galaxies can be seen with a naked eye?
25:53 [Alderaan] What it feels like standing on an asteroid being destroyed?
28:38 [Dagobah] Will NASA land on an asteroid?
30:58 [Yavin] How cold is it in space?
33:25 [Mandalore] Can we bring our sun to another star?
37:03 [Geonosis] Lunar probe flying with springs?
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[@-yeme-]

The Andromeda Strain is such a cool movie. I love the underground lab.

[@47f0]

Michael Crichton did a lot of research for many of his books. That lab was allegedly based on plans for an actual Department Of Defense lab that may or may not have been built.

[@adamhopkins6474]

Could we see the "surface" of jupiter with a radar mission like magellen. Would we see waves on a metallic hydrogen sea? Love the show

[@nicholashylton6857]

NASA landed on an asteroid back in 1999. At the end of its mission, the Near Earth Asteroid Rendezvous orbiter was soft landed onto the surface of the asteroid, 433 Eros. It wasn't specifically designed to do it, but NASA thought it would be a cool way to close things up. Pretty badass, IMO.

[@oldmandoinghighkicksonlyin1368]

NASA does some of its most memorable work when it's unplanned or outside mission parameters.

[@nevyngould1744]

​@@oldmandoinghighkicksonlyin1368 the original 'blue marble' springs to mind. Totally off-mission and spur of the moment. The conversation in the capsule is fairly amusing, bit of a panic to get the right kit to hand.

[@Bitchslapper316]

Thanks for making this content Fraser.

[@AliHSyed]

i'm shook by fact that a 1-Universal Mass black hole would have a radius of the observable Universe.

[@frasercain]

Yeah, it's pretty crazy.

[@petevenuti7355]

So if we are already in a black hole, and moving to or away from the center is the the same as moving forward and backward in time..and we are moving backwards in time (entropy works the same backwards and forwards), how can we tell that we are inside a black hole?

[@damirregoc8111]

Well, we aren't. It's not really a hole. You can't be inside of it. @@petevenuti7355

[@rogerdudra178]

At my age now, 74, I look forward to seeing another moon landing in my lifetime.

[@Technodude255]

As always! My jaw is wide open from amazement from this channel! Love the content!

[@ptervin]

Not to belittle the question of contamination--and your answer is spot on--I seem to remember the same "fear" when samples were brought back from the moon. Turns out it's all inert. We've done a lot of science on Mars so I suspect the same will be true. We may find bacteria from the past, but it's probably not doing much there now. But then again....

[@Alph413]

Just from the subjects of todays episode equals a thumbs up …looking forward to hear you take on’em

[@gamegoof]

How... do you make so much quality content

[@frasercain]

I have a time machine.

[@gamegoof]

@@frasercain That actually makes sense... Your hard work is much appreciated

[@lukasmakarios4998]

My favorite question & answer: Geonosis. I can't wait to see this!

[@ryantaylor1142]

Thank you Frazier and crew memberS

[@foxrings]

Yavin. I love how you broke down how heat is felt in space to help us understand this!

[@formarosastudio]

Tatooine ! Love a good mars life story

[@thedenial]

Alderaan: The Roche limit at that frame of reference gets my vote. 27:46 Fraser: …and this is the part that gets really cool… Me: I don't know, rocks lifting of the asteroid and floating around seems really cool to me. Fraser: *continues* Me: *redefines really cool*

[@frasercain]

So cool.

[@gary3808]

Tatooine Another great show, very informative.

[@dixiefish0173]

Interesting video thanks 😎

[@universemaps]

Coruscant and Mustafar. Many great questions and answer here! Thanks Fraser and patrons!

[@frasercain]

Thanks a lot, I'm glad you enjoyed it!

[@virutech32]

Geonosis Jumping rovers are such a dope idea

[@cavetroll666]

great topics thanks the content :)

[@Alien-ii2zh]

How close do you think we are to achieving interstellar travel?

[@bernhardjordan9200]

I would say 4.3 light years

[@Reyajh]

@@bernhardjordan9200 Well, that's practically just over the horizon!

[@oldmandoinghighkicksonlyin1368]

I don't think there's much point for humans to do that. The timescales involved are just too vast. We'd send a mission out and then get the results centuries later. I think we'd have to invent immortality, then a means to hibernate the crew, and have a singular, stable culture on Earth that's willing to invest resources over the course of several current human lifespans. It'd kind of be a bummer for the crew only to wake up from stasis, send a call back home only for no one to answer because we'd forgotten about them or are struggling to survive in the aftermath of world wars 3, 4 and 4b.

[@petevenuti7355]

I'm sure some religious cult will do it, if just so they will be remembered for more than a few thousand years... The UAE has the money, do they have any religious fanatics? Or a space program?

[@bernhardjordan9200]

@@petevenuti7355 there's always the risk of Mormons trying to settle in bug territory. If that happens I want no complain about Buenos Aires being wipe out of the map

[@bravo_01]

Great episode as always, thanks!

[@asbecka]

Aldebaran I think is the star you were thinking of. It’s definitely very similar to the Star Wars reference.

[@frasercain]

Yeah, I know. Stupid Star Wars mixing up my brain. 😀

[@nagoh04]

Tatooine. Thank you Fraser

[@eddielopez3041]

That’s a good point. We’re so worried about contaminating other planets that the same worry should be on our planet as well.

[@adirmugrabi]

i vote for Aldeaan. really good and interesting question. that would be one heck of an earth queke.

[@rgraph]

Your question about Mars life and contamination of Earth at the start of the video is exactly the plot of the film "Life"!

[@kingkiller1451]

There is actually a point at which you would expect a black hole to stop naturally feeding, as it grows stuff is able to orbit in a stable manner closer and closer to the event horizon until at a certain point (at least in theory) it could no longer form an accretion disk and could only feed from the occasional direct hit with near misses simply flying away or entering a stable orbit.

[@lukasmakarios4998]

And I thought that if a black hole exceeded its theoretical limit, it would explode and create its own new universe ... a new "big bang"!

[@pepopipo974]

11:30 even though probably doesn't exist a hard limit of the mass of a black hole, black holes may get to a point in which they can't get mass by accretion discs of gas, because they end up making the gas go away

[@revblade]

Dr. Becky has a video on the KZbin channel Sixty Symbols describing that limit. Although that does not put a limit on the top mas of a black hole, it certainly removes a primary means of black hole growth.

[@rJaune]

Coruscant - I can't wait to learn more about the early Universe with JWST. And black holes are always interesting.

[@frasercain]

Agreed. So many more stories coming out as we approach the 1-year anniversary of Webb's first science data.

[@revblade]

Dr. Becky has a video on the KZbin channel Sixty Symbols describing the limit of black hole growth. Although there is not a limit on the top mas of a black hole, There is a size at which acreation stops working. it certainly removes a primary means of black hole growth.

[@revblade]

The Sixty Symbols video is at kzbin.info/www/bejne/pniykHqAgZZqna8

[@frasercain]

Beyond accretion black holes grow through mergers.

[@BabyMakR]

They way I heard of how to make a stellar engine to move Sol was to build a Dyson Sphere and open parts of the sphere in the direction you wanted to thrust and the rest of the planets just followed along.

[@HebaruSan]

Alternate interpretation suited to a sci fi story: Mars had Earth-like life due to panspermia, but a super deadly omni-virus wiped it all out and has kept it suppressed to the present, and the Martian surface today is coated in layers of death-particles. Bonus points for tying it to the Fermi paradox!

[@ryantaylor1142]

🎉🎉🎉 thank you 🎉🎉🎉

[@MaryAnnNytowl]

Geonosis - I want to see these things happen before I kick the bucket!

[@Bryan-Hensley]

Wow, I learned something. Canada has a space agency.😊 If we are seeing a black hole that big that long ago, how big is it at this current moment?

[@lukasmakarios4998]

Big enough to swallow all of the universe beyond our "observable universe."

[@bernhardjordan9200]

That mirror/sun thing sounds like trying to pull yourself up by the boots straps

[@GrouchyHaggis]

Tatooine - I'm not sure how true the story is but I recall hearing during the Apollo missions, when they returned, they were put into capsules for quarantine. One person noting the insects crawling on the inside of the capsule (implying it wasn't airtight and, IF, there was a lunar deadly virus/bacteria, it likely would have contaminated Earth...) I also heard that they had to walk from the re-entry capsule to the quarantine one, which kind of defeating the point of quarantine...lol

[@PrinciplesMatter]

Wow! I don't know if it was mine he saw but I asked the question about the max size of black holes, I can't wait to see the answer!

[@frasercain]

I think we covered that last week? There's no limit to the size a black hole can be.

[@caseyford3368]

We seriously need to scan everything that comes back to earth, before it re-enters our atmosphere. Then clean of anything that would potentially be dangerous for earth.

[@roccov3614]

Alderaan: I thought that what tore orbiting bodies apart as they approached the roche limit was that the closer side has a faster orbit than the back and the forces trying to tear the body apart are larger than the gravity keeping it together. Is that wrong?

[@rogerdudra178]

Greetings from the BIG SKY.

[@heaslyben]

Note to Artemis II crew: DON'T STIR THE TANKS!

[@stevemotuel]

The film Life springs to mind 😂😂😂

[@sarcasmo57]

Lets build that mirror sail thing. I want to go touring.

[@BobbbyJoeKlop]

35:45-Hoag's Object comes to mind. Maybe it's a galaxy reorganized to be a giant gravitational lens telescope? And it's looking right our way. Moreover, the other galaxy inside of it from our vantage point could be part of the same project. As it looks to be formed in a similar manner. Albeit at a much greater distance. Imagine the observational power of an entire string of galaxies, millions or billions of light years apart, reorganized around telescopic principles. Like a series of well-crafted lenses. Organized to work together.

[@pelewads]

Tatooine, made me laugh several times

[@MalcolmJones-bossjones]

Just started the video but viruses I’ve always wondered if we are afraid of something like this ! Looking forward to your answer!

[@jgunther3398]

viruses and their hosts have evolved together and ability to infect a particular host is an evolutionary trait

[@Andrews87]

@@jgunther3398 have u seen the movie Prometheus? yeah never know.... maybe the virus is a distant ancestor of the ones on earth?

[@oldmandoinghighkicksonlyin1368]

Watch the movie Fraser refers to _Andromeda Strain._ It's a bit dated with the room-sized computers and mechanical switches for inputs, but the theory is still sound. It's a nice little sci-fi thriller from the 1970s.

[@MalcolmJones-bossjones]

@@oldmandoinghighkicksonlyin1368 needed a good sci fi movie to see, adding to the list, thank you friend!

[@picturesalbum4532]

Rather then return it to earth they should put a small lab on the moon for studying it.

[@christophermullins7163]

They should move testing of anything that could infect humanity to the moon. If COVID was in a lab on the moon it never would have gotten out. I suppose it's possible that the release was intentional.. can't prevent that.

[@Handles-R-Lame]

Sure but what if the astronauts studying it bring it back with them, or maybe has an incubation period so they show no noticeable symptoms. Even worse what if it had some sort of extreme unknown morphology and having a more plentiful environment than what it had on Mars like what a moon base or ISS would have or better yet the human body.... 😱 Be like the movie Red Planet but the algea is microbial and much more deadly. 😖

[@davesworld9537]

Or the lunar gateway perhaps?

[@MadWorld75]

I wanna go get the hell out of here.🚀

[@tinman199711]

Artemis 3

[@jimcabezola3051]

(Sigh...) Here I was hoping we'd bring back Europan space whales...from Mars... Mahalo for another great episode, Fraser. Oh...and "Tatooine" is my choice this week.

[@ryantaylor1142]

Aloha from Maui

[@jimcabezola3051]

@@ryantaylor1142 Aloha from O’ahu!

[@JamesCairney]

32:02 a spark would be a better analogy, a spark has enough heat energy to make it glow white hot but it doesn't have enough energy density to make a few skin cells warm up enough for you to notice.

[@MusikCassette]

Dagobah what is the nearest asteroid to earth in terms of delta V and how much water does it hold?

[@stevemullin1195]

Just have the mars samples dock with the ISS to be analyzed

[@chrisgriffith1573]

It only kills THEM! LOL - so practical!

[@JohnSostrom]

Fraser, you discussion concerning about how to know if you are looking at a much more advanced civilization started my brain asking a simple question. If this advanced civilization we are attempting to find has rebuilt their galaxies into a more advantageous arrangement for their species, how would you know it when you see it? After all, if they are truly that far advanced from us, then they have likely realized truths in physics and space that we have not even thought of yet. It would be like asking a microbe to recognize a rearrangement into a human. Can we possibly even guess what to look for?

[@jpjh8844]

The thought of bringing a sample of Mars back to Earth is both exciting from a scientific stand point, and terrifying from a possible biohazard stand point. The things we can learn from samples is mind blowing, yet if there are unknown types of bacteria, microbes, spores, viruses, is terrifying! It's also terrifying to think we may bring back microbes and bacterias that we introduced years ago, but then those microbes and bacterias evolved to survive in Mars harsh environment. The Spanish destroyed the North, Central, and South American societies by introducing diseases that they had no natural immunities or medical technologies to prevent from spreading. One thing that would be interesting to see if they can do would be adding a Mars module to the ISS that is the equivalent of a level 4 bio lab to be studied in space to determine if their are any hazards to humanity. If deemed safe, then the samples can be brought down to be studied by scientists across the planet in regulated, safe labs.

[@ztublackstaff]

Aldebaran wait I mean Alderaan… great episode

[@frasercain]

Star Wars messed up my brain.

[@ZOMBIEHEADSHOTKILLER]

Funny, i recently started an unlisted videos Play list, and it is mostly your videos.... It's funny to me that you mention it.

[@frasercain]

Oh, I saw it. 😀

[@UpperDarbyDetailing]

Roche limit has to overcome the gravitational binding energy.

[@daithiodalaigh8914]

. De ol' "shortage of materials" problem ... for space travel ... Sorta adds more credence to aliens here in the past digging for gold, and as a result.. us humans ... ( food for thought, or grown locally whatever planet/moon/asteroid you're on) .. Great show, great work

[@stevekennedy5165]

Curuscant. When black holes collide, do they merge together, pop together like a bubble joining, or do they fly together like magnets when they get close?

[@CarFreeSegnitz]

33:25 Shkadov Thruster concept is a poor cousin to the Caplan Thruster. Shkadov harvests the momentum of photons while the Caplan uses proton & neutron momentum. The most exciting part of moving our sun is the idea of reversing the solar system’s path around the Milky Way. Couple that with lily-pad interstellar missions, hopping to stars as they make “close” passes. Close encounters would go from every few hundred thousand years to every few centuries or a few millennia. The waayy out in the future rope a red dwarf for an intergalactic voyage.

[@deisisase]

How dense are the star systems in the Carinia nebula? Are they light-years apart or a few light-days apart?

[@agentdarkboote]

The whole thing is 450 light years across, so the stars are probably still at least a few light years apart on average.

[@mihan2d]

I know I proposed this question before, but what are the most realistic ways of supplying power/accelerating the payload on an Earth based orbital elevator? As in, how would you reliably and efficiently supply power to the spacecraft moving at least a few thousand km/h via stationary tethers without wearing them out at those speeds? There has to be some contact between the spacecraft/gondola and the tethers, since the only conceivable contactless method being coilgun-like acceleration would be too inefficient and would require mounting a ton of heavy infrastructure alongside the tethers weighing them down significantly. It seems like everyone overlooks this issue behind debating on how to build the structure itself

[@fraliexb]

(Bespin) 23:30 you talk about the sun would be the A while the 1st planet would be B, and 3rd C. But what if it's a dual solar system, wouldn't then the 2nd sun become B? Especially if it's a smaller sized or obscured sun, that wasn't discovered until later as a dual system.

[@frasercain]

The numbers are in whatever order the objects are discovered. So if you discover it's a binary star system, the two stars become A and B.

[@roccov3614]

31:00 I heard a story once where a mountain climber at the top of a mountain tried to boil some water to make a cup of coffee but ended up with coffee that wasn't that hot, because the boiling temperature at that altitude was so low.

[@YTEdy]

I like that. I'll kick in a couple of bucks too . . . to move the Sun. Problem, though. That massive reflective thing that's balanced between gravity and pressure - where do you put it? Wouldn't it shade the Earth from time to time . . . for months at a time. Maybe build it above or below, but that limits the direction of travel. Still a cool idea.

[@TheJollyGamerJoe]

What is the theoretical fastest speed a rogue planet could travel through space? Let's say one spends billions of years getting the perfect speed boosts from slingshotting around stars and blackholes (without destroying it). Could we ever ever see a rogue planet hurting through space towards us at unnatural speeds?

[@mickmacy6161]

Tatootine- Wu!

[@jasonkinzie8835]

The last time humans walked on the Moon I wasn't even a year old. I'm currently 51. This is exciting for me because it isn't history. It's current events.

[@alfonsopayra]

MANDALORE (joli crap that mirror idea.. )

[@oneanddonetzone3673]

I agree with everyone who have stated not to bring it back to earth. We have a scientific space station that should be in the top running.

[@frasercain]

Yeah, I really like that idea too.

[@dustinking2965]

I, for one, welcome our new space virus overlords.

[@victormarioardilajr.6021]

I have a question. What are the limiting factors on the number of gravity assists that can be performed? And, what is the fastest theoretical speed that can be reached through this method? Thanks.

[@mub3ady]

Hi Cain Given that we see celestial objects as the were the past, and if hypothetically you was travelling toward one of them at the speed of light would that object appear to be on fast forward, for example the rotation of a galaxy, would it be noticeable?

[@TiagoTiagoT]

Hm, I thought that "spaghetification" was actually about how space gets so much more compressed the closer you get to a blackhole, that to move lower, stuff gets horizontally compressed into less space, like as if spacetime was shaped like a 4D funnel, horizontal movement converge due to the geometry of spacetime as the down vector of horizontally adjacent points rotate more and more towards each other, and you're essentially extruded thru spacetime like spaghetti dough coming thru the spaghetti machine...

[@airplayn]

Naboo. Was that free return orbit illustration right? Wouldn't you have to icicle the moon in the opposite direction for a free return orbit?

[@steveleach6641]

Assuming you’re operating in/on a moon base or mars base. Would a lathe or milling machine work as is or would extensive modifications be required to make them work correctly?

[@itsmodsiw]

[@SirLothian]

Hi Fraser, not sure if this is in your area of expertise, but I have a quick question about the "big rip" I have heard that in 22 billion years, the big rip will tear apart atoms and even protons, and then the fabric of space itself. Is this a real thing, or is this just projecting current trends past the reliability of our ability to predict? Thanks

[@Andrews87]

big rip or the big crunch. i personally think the big crunch is more likely to destroy us. lol

[@MusicalSawMen]

If the singularity before the big bang was a black hole, and nothing can escape from a black hole, then we live in a black hole right now !

[@m.cockcroft4737]

QUESTION: In Hoth ( and all inhome views) what is the critter on the top of your bookshelves? It looks interesting... Is it handmade ? If so, using what media & technique has been used? Thanks for your answer.

[@frasercain]

It's a homemade stuffed crab. An artist made it for my mother when I was a little kid.

[@bingomat1980]

If you went in a straight line through the universe, would you eventually get back to where you started? Also, people talk about travelling to Mars and how close that possibility is. However, has there been a solution to the amount of radiation the astronauts would have to endure on the way? Finally, do you believe in planet 9? Cheers. I like your vids.

[@kkgt6591]

Hi Fraser, what's happening with the Chinese Fast telescope, any discoveries from it?

[@foro1]

Hey Fraser, why when the Big Bang happened all matter didn’t go into one big all mighty blackhole? What’s the scientific explanation? Love your work, Thanks :) Coruscant.

[@frasercain]

You need an overdensity in one place to create a black hole. Everything was equally dense so it couldn't collapse into a black hole.

[@tdanjones]

So you said that we can ask questions on any of your videos for the question show. I was just wondering this. You say all the time that other galaxies are moving away from us at the speed of light, but at the speed of light there is the time dilation, so how does that square without making the Sol system the center of the universe? And if we are moving away from them at speed then why don't we experience the time dilation that is theorized?

[@mhult5873]

Tatooine 🙂

[@Raz.C]

Hi Frasser Here's a tricky question: Given that exposure to radiation can trigger mutations in DNA and that such a mutation could lead to benefits that makes it easier for an organism to survive in that environment, do you think that humans might experience divergent evolution as they start living on other planets? I mean, let's just say that we've got humans living on Mars, the moon and Earth. Each of those places will be exposed to different amounts of radiation as well as being very different environments from each other. Considering how different such environments are, do you think that we could see up to three distinctly different species of humans living on each planet (or moon) within a few thousand years? Seeing how quickly artificial selection can result in differing phenotypes and genotypes, I don't think it's unreasonable to think that we might see human speciation events within a few thousand years, given how wildly differing the environments would be (ie- different gravity, different amounts of radiation, low ambient air-pressure/ no pressure, etc). But then again, I'm not a biologist, so my opinion is just an opinion, not a scientific prediction.

[@BabyMakR]

My vote is for Mandalore

[@boballanson8671]

Hi Fraser a question. I read somewhere that the earths magnetic field protected the atmosphere from being stripped away by the solar wind. Venus does not have a magnetic field and has a massive atmosphere. Its atmosphere must be replenished by something probably vulcanism. What I want to know is if the stripped away atmosphere can be detected as it gets swept past earth? Is Venus atmosphere stuff more plentiful when Venus is on the same side of the sun as us?

[@everychordever4339]

It seems to me that LeSage's theory of gravitation, by reversing the direction of action, makes dark matter unnecessary. Thoughts?

[@joseph-mariopelerin7028]

Since we cant afford to bring samples back to Earth... we should focus on the mega lab on Mars,

[@LordBitememan]

Could a star be so massive that even it's own supernova couldn't blow it apart?

[@frasercain]

If you've got a supernova, you're already in the exploded star stage.

[@NoahSpurrier]

I’ve always wondered if we should allow astronauts to return to Earth if they do discover life outside of the Earth’s biosphere.

[@missusnat870]

❔If a black hole could consume the mass of the observable universe, and have an event horizon the size of the observable universe, could our entire observable universe theoretically be inside of a gigantic black hole and our understanding of time/space is already what one would see/experience inside of the event horizon of one of our black holes? Universes inside of universes... just fun to think about!

[@PatriciaOConnorBonsaiBalcony]

Coruscant

[@pewterhacker]

@11:39 If a black hole with the mass of the observable universe has an event horizon the size of the observable universe, then wouldn't that imply that we must be inside a black hole? And, since the observable universe is shrinking, doesn't that also imply that mass can escape from a black hole?

[@gordonproctor5719]

Is our observable universe inside it’s own event horizon? If so, could an expanding universe mean that some mass within this event horizon is escaping as it becomes less dense?

[@poisontoad8007]

On returning Mars samples, is a risk being 'pretty low' good enough? I'm not sure if Mars bacteria/viruses (if they exist) not evolving to live on Earth environments is a valid safety argument. Introduced noxious weeds and animals evolved to live in their native environments. It is when they are introduced to an environment without their endemic checks and balances that they become such a problem.

[@nicholasmolitor178]

I'm trying to research realistic propulsion technology that could allow astronauts to travel from earth to Neptune in a few month for a scifi thriller i'm writing, I've seen the announcement for a rotating detonation rockets, and Nuclear powered rockets that could get to mars in 45 days. I've thought about RAIR, and VASIMR. But I don't know if they're fast enough or practical enough, to reach the goal I want. Any suggestions? What your thoughts on the announcement?

[@lachlanthomaslangmead1651]

Not sure if there’s anything short of a fusion torch drive that’ll get you to Neptune in that timeframe.

[@olencone4005]

If it helps, one recent proposal from NIAC that's looking promising is a pellet-beam propulsion system -- it's sort of like an advanced light-sail variant. From the NASA announcement: "Inspired by the sail-beam concept we create a pellet-beam - a beam of microscopic hypervelocity (>120 km/s) particles propelled by laser ablation. The pellet beam is then pushing a spacecraft to desired orbits and destinations, including fast exit trajectories." They believe it could be used to propel a Voyager-style craft to Neptune in a year, about a third of what it took for Voyager 2.