AI Pilots for Space Missions, A New Big Bang, Falsifiable Dark Matter | Q&A 236

[@therealanyaku]

As a person who remembers the 1950's, I have to disagree that a person from then wouldn't be baffled by the modern world. Just confining my point to computers, my father repaired computers for IBM. When I said my daddy repairs computers, the other kids would respond "What's a computer?", and adults would be "what? Computer is the job title of a person skilled in the use of a mechanical calculator". Every election day, NBC would trot out the UNIVAC computer, and it was just as silly and baffling to most people as the Wizard of Oz.

[@sjsomething4936]

I don’t remember quite that far back, but I’m old enough to remember having to go over to the TV and turn the dial, select UHF or VHF, and do the fine tuning of channels not getting great reception. I agree we already have so many sci-fi things: - enormous rockets like Starship, Ariane 5, Falcon Heavy, Atlas 5, Long March etc. launching _weekly_ and *landing like they did in 60s science fiction* - a huge amount of the technology needed to establish moon or Mars bases sorted out or in at least prototyping phase - working on a NUCLEAR ROCKET!! - on the cusp of understanding how to extend human life for possibly centuries - a decentralized and fairly democratized communications network spanning the globe, including the use of space satellites - have incredibly powerful minicomputers in our pockets that allow us to instantly communicate with anyone across the globe - can use the minicomputers to ask the huge supercomputers questions almost at will - are on the cusp of creating artificial general intelligence (if we haven’t already… debate in this area) - very soon will have flying taxi-like vehicles - sensors capable of being monitored in almost every corner of our cities and also in many remote locations - have gone to the deepest depths of the oceans - have cured or are near a cure for hundreds of diseases That list is far from exhaustive, and many of the innovations are so incremental that we almost don’t notice them - stuff like LEDs, OLED TVs, keyless entry vehicles, ABS brakes etc.

[@larslindgren3846]

@sjsomething4936 I don't think many people have a minicomputer in their pockets they are way too big. Smartphones are a type of extra small microcomputer. A minicomputer is larger than a desktop computer.

[@sjsomething4936]

@@larslindgren3846 ok ok I’ll give you that I used a bit incorrect terminology… I know what a minicomputer is, I’ve either done system administration on or hardware support on: zSeries mainframes (formerly known as MVS, S390 etc. under different IBM marketing names), AS/400 now called iSeries, VAX, and DEC Alpha systems, so fairly familiar with the types of computer you mean. I was also an AIX administrator for about 12 years. In truth the iSeries and pSeries systems are basically just a standard size server nowadays running either different hardware and or software. I guess the right term might be “miniaturized computer”. 😉

[@garetclaborn3659]

Re: weekly space hangout's on ramp for communicators, Maybe you could send new communicators 3-5 of the questions once a week, jump on for 2 segments of an interview and/or have a form for them to submit shorts that can be cut into a bigger theme in exchange for channel shoutout?

[@frasercain]

Ooh, I like that. Have some guest spots from people.

[@PestOnYT]

Fraser, let me ask that question that puzzles me for quite some time. We know that, as explained by general relativity, time on earth's ground is progressing slower than in earth's orbit. So, there's a factor or about 45 x 10^-6. But, earth's orbit itself cannot be the "ultimate" reference clock as our Sun and our galaxy have their pull on spacetime, too. So, somewhere in a void very far from any mass, there might be a point at which time is at its fastest rate. I'd like to know if the relation between that reference point and earth's ground level is. Are we 0.001, or 0.002... etc. off? Anyway, I think that all the measurements we do on earth are slowed down by that factor. Meaning, that measurements from events from far away are observed slower than they should be. That difference of constants in our formulars etc. may add up to the difference we see when comparing the results of the two methods used in what we now call the crisis of cosmology. As one of the methods (to my understanding) is independent of our time delay, while the other isn't. Any thought on this?

[@orbitalrocketmechaniccain3150]

To add to this, so even if you are on the ground or in space isn’t the entire solar system swinging around the center of the galaxy and the galaxy itself moving. Meaning that the speed you move in orbit is relatively canceled out by the total movement of everything.

[@bjornfeuerbacher5514]

I once saw that question answered, a long time ago. If I remember correctly, the factor is _very_ small, on the order of at most 10^-4. So no, that couldn't explain the crisis in cosmology.

[@frasercain]

Everything is relative. But regions separated by the entire observable Universe experience about 30,000 years difference in time due to time dilation.

[@bjornfeuerbacher5514]

@PestOnYT: By the wy, where did you get the number 45 x 10^-6 from? Looks way to big to me. :/

[@michaelhopkins9726]

As our host said, it is all relative. You used the "ultimate." Nothing is that. Every frame of reference is just as good as any other.

[@olivergrabowski4278]

Vendikar Really good description of dark matter observations! Very matter of fact - this is what we see, we don't know whats causing it but it's definitely a thing.

[@GrouchyHaggis]

Vendikar - Great answer.

[@GrouchyHaggis]

Rimworld is great!

[@lordzombie]

your description of rimworld reminds me a bit of the MAX show Scavenger's Reign, rag tag group surviving on an alien planet. its pretty amazing. lots of loong trippy sequences of alien biology, complex symbiotic relationships between species and their interactions with these lonely few humans with their own psychological baggage.. very cool show

[@agshiv01]

You do a GREAT job of letting us know what is known by scientist! You tend to push back against unproven theories (smart choice). If we want to know more about theoretical stuff (ie what's happening in a black hole, string theory). Where would you suggest we look that is well thought out, and readable to non PHD audience? Is there a good string theory for dummies site you would recommend?

[@frasercain]

If you want more theoretical, but still evidence-based, I'd suggest following Sean Carroll's Mindscape podcast: www.youtube.com/@seancarroll

[@petersvancarek]

hmmm what is happening in a black hole when there is zero time dimension under the event horizon? The time literaly stops there. Now think about it... What can happen if time doesn't run?

[@lunafoxfire]

In reference to your interviews: those are one of my favorite parts of your channel and one of the main reasons I subscribed after I found you! They are amazing and in depth and really let us as the public connect with the real scientists doing super interesting things.

[@extropian314]

2:26 Wow, really informative and beautiful visual aids for this asteroid question.

[@Pat19997]

I think having debates amongst astrophysicists would be entertaining. It’s nice that there is collaboration but hearing a counter hypothesis would be great.

[@Phoenixash-delfuego]

Your picture quality is so sharp it's like you're popping out of my TV.

[@cavetroll666]

Thanks Fraser cheers I'm listening from my boring job in Toronto but this brings me into orbit 🙃

[@avejst]

Vendikan, Great analogy of the speed-problem 👍

[@j7ndominica051]

Is the small orange loudspeaker on the shelf behind Fraser Cain's back functional? People have a lot of free space for such decorations. Go through the stargate and give us a greenscreen shot of some trees. We haven't seen those in a long time.

[@charjl96]

Remus! I like that way of thinking. Even if there's a reasonable answer, it's still good to be curious in such a meta way

[@lindajirka5020]

Thanks for information about where to post questions.

[@frasercain]

For you, the best place is when I make the call every month for Patrons. Around the 15th

[@BoyKissBoy]

I can't sit up in the middle of the night to watch the live show, but you keep telling me how much I miss out on. Do you post the complete live show somewhere? Is it available for patrons?

[@frasercain]

If you're subscribed to the channel and have the notification bell set, then you should get an email with a link to the show. That remains permanent. We also put a link to the full livestream into the publicly available Patreon feed. For example, here's the one I released today: www.patreon.com/posts/ai-pilots-for-q-92024100 We also put the full audio for Overtime into the patron-only podcast feed. Hopefully one of those ways works for you.

[@garetclaborn3659]

We often hear about MOND/similar being Dark Matter candidates, but almost never hear about experiments testing for anything but particles. Are there any results that shows how astronomers consider modified gravity ideas, to know if a wild theory has any 'there there'? I'm always wondering the same thing: Could the 'excess' momentum of galaxies be the cause of lensing rather than the effect ?- In the same way a photon in a box has gravitational effects, that momentum correlated to dark matter is confined energy. The theory goes maybe this momentum was instead imparted as a blob of early gas becomes unbound from distant gravitational masses like a slingshot, but how would I even know if the idea is stupid haha

[@willemvandebeek]

Aeturen You are not alone, I miss the Weekly Space Hangout too, especially back when they were live on Friday evenings European times. I liked it best, when you could ask questions in the chat and Fraser would ask those questions for you to the guest.

[@AliHSyed]

Getting to the L3 Lagrange point seems tricky

[@ReinReads]

Vendikar This is the best review of dark matter I’ve ever heard. Thank you for making this easier for me to explain this to others.

[@beastlysnippets]

Hey Fraser, QUESTION :) I read, Galaxy NGC 7727 has two central black holes, distance 1600 lightyears, and that those are estimated to merge in 250 million years. Why would they? I'd expect them to orbit each other basically forever. Can they lose that much energy by emitting gravitational waves?

[@samhill206]

Fraser, is there any reason why a Mars lander has not been landed near Olympus Mons? Would love to see a lander photo of Olympus Mons.

[@ioresult]

Aeturen: more collabs!

[@jeffmathers355]

Hey Fraser, a question just popped into my brain: Is there any connection between Venus' slow rotation and her lack of a magnetosphere and tectonic plates? And just for fun - could future us trigger those things by flipping her upright and increasing spin? Thanks👍

[@formarosastudio]

Aeturen : Emerging Theories - New ideas from new minds in Space and Planetary Research. Bring on young scientists and technologists who are interested in having more exposure. Bonus : Make it live and have the audience help with the questions 😂

[@db459]

Frazier, I’ve been listening to you since the early days of Astronomy Cast. I appreciate all you and Pamela have done for space journalism. Question: In the dark matter debate, what role does relativistic time alteration have on the perceived galactic motion that leads to the need for dark matter to solve the problem?

[@thefastestest]

Hi Fraser, that was excellent and very clear description on dark matter. Thank you.

[@bmobert]

Question: I understand you can make a space elevator from the surface if the moon to the L1 or L2 points. Can a space elevator be made and made stable from the surface of the moon and L4 or L5? (And, yes, I mean Earth-Moon Lagrange points.) If so, what kind of material would be needed to withstand the stresses?

[@nicosteffen364]

When is the topic "Gossip from the Minbari Communiuty" comming? Its a Babylon 5 refference, Universe Today!

[@BabyMakR]

Would the Sun-Jupiter L4-L5 be a good place to put a gravitational wave detector or are they not stable enough for the detectors to work?

[@terminusest5902]

When did Bosom particles begin affecting gravity. How did the mass of the big bang escape the gravitational mass without forming a hyper supermassive black hole.?

[@kevinsayes]

Hey Fraser, thanks as always, I listen while I walk and very much look forward to it. Question: When a paper is submitted for publication, how is it reviewed? Is there a dedicated team that conducts experiments and checks maths, etc for each specific paper, or do they look at results from work that’s already ongoing? Basically: how does the review process work?

[@frasercain]

When someone submits a paper, the journal sends it out to other researchers in the same field to give it a look. But their review is unpaid and generally pretty high-level. They're not necessarily double-checking the math, although they might. Peer-review isn't as exhaustive a process as we might hope.

[@roccov3614]

Vendikar Hey, Fraser, you know how you have different forces that dominate at different scales, like electromagnetism at molecular scales and gravity at macro scales, what if there was a force much weaker than gravity that comes into its own at galactic scales? Would that explain the strange rotations of galaxies? Has anyone suggested such a thing?

[@dreistedrei1543]

is quantum entanglement generating extra mass and could this be dark matter?

[@ashleyobrien4937]

Gravitation of galaxies is one area where our idea of gravity fails, they tend to stick together much more than they should, especially at the outer arms, but what about gravitational lensing ? like when we see four or so copies of a lensed object like a distant galaxy being lensed by a bunch of galaxies in the mid field, does our theory for gravity correctly predict the images we get ?

[@Dan-nj8du]

Seems to me SpaceX has had AI landing the Falcon for some time.

[@francistony4306]

Hi Fraser, apparently the black hole accretion disk can be 10 light days wide, but how thin is it? It would be crazy to have something 10 light days long and as thin as a molecule. BTW I started adding iPhone reviews to your podcasts. I hope they are coming through.

[@andrewnicholas9079]

Can't tell you how long a galaxy forms or how. But can tell you how the universe formed when and how. Interesting

[@RoryJamesFord-rn9yu]

I have a question: what would it take for a Mars lander (ie Starship, or the sample return rocket) to take off from the surface of Mars? I heard that there is basically no atmosphere there, does that mean it's super easy?

[@karlharvymarx2650]

I think I have heard of using pulsars to navigate in space. Would it work similar to GPS but with the nearly constant pulses of the pulsars acting as atomic clocks? So knowing the relative arrival time of each pulse at your ships location would tell you where you are and perhaps more pulsars in view would increase accuracy? How accurately could position be known assuming a handful of run of the mill pulsars? I assume there is some apparent variation in the signal timing because of changing gravity distortions distortions between here and a pulsar, and maybe debris orbiting the pulsar very slightly altering its spin rate and wobbling it but I don't have a feel for how significant all of that is. I guess my main question is: Could several missions be combined in making a long baseline radio telescope array like you mentioned if pulsar timing were used or at least observed? Perhaps enough spacial and time accuracy for observing rings of light orbiting black holes like a recent guest talked about, watching for movement of dark matter, and watching gravitational waves? Maybe 1 satellite could be added "above" the sun, out of the orbital plane of 3 at lagrange points, a tetrahedral formation, using light sails to stay near equilibrium between solar system gravity and light pressure to give a more 3d view.

[@mrjp2149]

Is the singularity in a black hole the 4th dimension, or 5th if we consider time a dimension? I often think of the singularity in a black hole as an abstract fourth dimension within our 3-dimensional space. The concept that a black hole's event horizon defines a spherical region in 3D space accessible from all directions, that marks a boundary where conventional physics transitions into a 4th dimension or "singularity"

[@cmjnwd]

Posting this comment less than 24hrs after the photo of Dinkinesh was released. Do we know the exposure time, aperture, ISO of the Lucy camera? Is it even possible to compare to a DSLR or is it more of an 'apples and oranges' situation? My partner asked me why the asteroids were so bright so I thought this might be a good question to post here. I assumed it was because the camera is set to take pictures further from the Sun, but could the asteroid be made of more reflective materials? Bennu appeared pretty dark I'm guessing due to it being made of alot of carbon.

[@noahway13]

I'm sure you get this every week. What would happen if a large star were on the edge of a black hole, and the star went super-nova, what would happen where the beam hit the black hole? ? What if the black hole were small, could a black hole get hit with too much material and get 'clogged up' ?

[@denmaroca2584]

There's a limit to the rate a black hole can feed. The rest goes into an accretion disc and either gets eaten later or is blasted away in jets caused by the intense magnetic fields in the disc.

[@frasercain]

A black hole can get clogged up, that's why we see bright light coming from actively feeding black holes. They're choking on too much material, like a messy eater.

[@iain1209]

Hey Fraser. An astroid of varying sizes that collides with the earth would understandibly cause varying damage. The bigger it is the more damage. How big would an interstellar object hitting the Sun (not the earth) need to be to become an extinction event on earth? I read a scifi where a planet sized object was driven to a % of the speed of light into a star to sterilise that system by making it go nova. Obviously pushing the speed up to %SoL would increase it's kinetic energy,but what if it was only traveling along like a rogue planet?

[@mhult5873]

Cait is my vote of the questions 🙂

[@NunoPereira.]

I would like very much to be a science communicator in space exploration, astronomy or other science domains, if possible in a professional scope. One suggestion would be if you could share a list indicating the people you know (science professionals, magazines, newspapers, radio stations, etc) that might have real interest in science texts or news. After writing some articles for evaluation, if considered satisfactory, some type of agreement could be defined. Do you think this idea could work? Or maybe in other format? Thanks

[@adam-stark]

Question: how come we are in the orbital plane of our solar system and we have a transit of Venus only perhaps twice a century, while we are looking and seeing exoplanets around other stars blocking star light on most or every orbit? Mercury has an 88-day orbit and we see 13-14 transits per century.

[@aeroskiff]

Hi Fraser, how fast does the influence of gravity travel?

[@frasercain]

At the speed of light

[@mrJety89]

What would be the best place to "park" an asteroid survey satellite far from the ecliptic, sort of looking down on the solar system. Kind of like on the animation you show at 4:22

[@chrissscottt]

Great show as usual and thanks for answering my question Fraser.

[@frasercain]

Glad to do it.

[@RICK82873]

Thank you for the explanation of dark matter. Made sense for the first time. Question is it possible we can’t find dark matter because there is none here. We would need to go and collect some from a place we just can’t get to yet?

[@pelican6665]

How do you measure the rotation speed of a galaxy. Aren't they pretty big and pretty far away?

[@frasercain]

You measure the redshift of the light from one side compared to the other side. You'll get a noticable shift that tells you how fast it's rotating.

[@kadourimdou43]

How near are we to being able to see the first Stars. Could we be wrong that they would be super massive.

[@AEFisch]

Is there a comet or object redirected to Venus that could trigger changes in the atmospheric dynamic? Adding massive amounts of water or another catalyst? You have gone as far as discussing moving moons, so slightly more to the point.

[@busybillyb33]

17:10 Hi Fraser, I have a question regarding the star orbital speed as a function of distance from the galactic centre not matching expected calculations from what we know about gravity. Has it been possible to test this out to much larger scales: observe galaxy clusters to see if galaxies orbiting the core of the cluster follow the same pattern and deviate from what would be expected?

[@denmaroca2584]

Yes. In fact Frirz Zwicky did just this in the 1930s and noticed that the gakaxies were orbiting as if there was a large amount of unseen matter. He coined the term 'dunkle materie', translated as 'dark mattr' for this apparent unseen matter.

[@VernAfterReading]

Comets, comets, comets. I get we've mapped nearby Asteroids, but what about Comets dislodged from the Oort cloud? I think we're still pretty much defenseless against those, and worse, we'd get very little warning. Hopefully rare, and cross fingers I guess.

[@frasercain]

Unfortunately they don't get bright enough to see until they're within the orbit of Saturn or so.

[@ReinReads]

I’ve always thought L3 would be the perfect spot for our future antimatter factory.

[@gary3808]

RISA Interesting as always.

[@frasercain]

Thanks!

[@bbbenj]

Thanks a lot 😊

[@jamescarlisle3770]

Solar system and Milky Way differ significantly in that the distribution of mass is more like a solid in the galaxy than in the planet systems.

[@phoule76]

How many Lagrange Point questions could orbit around the L2 Lagrange Point, when taking into account the troll-y Lagrange Point questions?

[@abstractedaway]

Speaking of possible signs of life, there was talk of phosphorus and organic compounds detected in the ice plumes from Enceladus. Some were saying "There's no explanation for this other than life." How is that doing?

[@frasercain]

There aren't any spacecraft at Saturn right now, so no new data to study. That's why we really need a mission to Enceladus.

[@PrometheanConsulting]

re: Science Communicators - PBS has a lot of online content for life sciences stuff that seems to fit your description. The format is largely essay-driven.

[@patrickradcliffe3837]

6:31 for manned spacecraft absolutely not. I would even question it for space probes. Right now AI is failing badly "Garbage in, Garbage out" just one look at who is programming the AI, they insert their personal bias into the program. Unless they come up with screening process for programmers it's only gonna end badly.

[@michaelsilver9411]

You are awesome love your videos

[@oldmansailor]

All that is the universe is still the singularity. We and everything of matter is just the projection out of the singularity in vibrations. Our actual being is still at the singularity. That is why you get quantum entanglement, every particle is still a part of the singularity as are we.

[@michaelgiles2347]

Would it be possible to construct an infrared telescope that pointed towards the sun but utilized a chronograph to protect its instruments in order to get a better view of near earth asteroids?

[@Starman_67]

VENDIKAR 🤘😎🤘

[@arlisnarusberk]

thank you

[@Dan-Simms]

More people should play Rimworld, it's so good!

[@patrowan7206]

Love the video, hate the music. Edit: Fantastic show!

[@whiteygaming6427]

If a spinning object spins faster when compressed why doesn’t a black hole spin infinitely fast if it is compresses to a singularity? Thank you for what you do!

[@frasercain]

A black hole's rotation speed is limited by General Relativity, so there's a maximum speed they can spin. Some have been found spinning at that rate. :-)

[@DrDeuteron]

There's nothing spinning, all that angular momentum exists in the spacetime of the BH, leading to strange things like the ergosphere. If the max J were exceed, the ring-singularity would pop out of the event horizon, and the experts don't like nudity.

[@humbugnh]

Q: why is it that the math of random walks (or something very similar) doesn't preclude the certainty of Boltzman brains coming into existence? For instance, in a 3D random walk, there is only a 34% chance of the 'particle' returning to its origin. Wouldn't the same apply to a 3d universe that is expanding faster than groups of particles can randomly form specific patterns?

[@frasercain]

A random walk depends on a previous position, and yes, you won't get a complete exploration of an infinite space. But in an infinite universe, different regions are completely disconnected from each other so you're effectively rolling the dice at random for each part. So random walk doesn't apply.

[@DexLuther]

15:05 Isn't it more likely that we don't understand gravity on galactic scales? It seems silly to essentially be creating a "god of the gaps" for lack of a better term. Why not skip a step and just assume we don't fully understand gravity, especially on larger galactic scales? That way we don't have to invent things we can't prove or disprove.

[@samanyamah-adkins4293]

For me, Cheleb is the winner!

[@svrcinamarek]

"Valuable life lessons from Rimworld" lol

[@frasercain]

That game is all about preparation and imagining all the horrible things that could happen to you.

[@bongandbeer]

@fraser is there ANY doomsday scenario you could possibly think of involving cern or another collider?😅

[@TibbersandTvStatc]

happy halloween

[@ChemEDan]

What are the prospects for nuclear SRBs?

[@EricJW]

Another great episode. I have to second Rimworld being my favorite video game of all time. If I had to pick a runner up, it's probably Stellaris, but that's less definite.

[@frasercain]

Stellaris is pretty great, but I've got a few that would tie for second place, like Project Zomboid or X-COM

[@EricJW]

@@frasercain XCOM is definitely in my top 5. Haven't tried Project Zomboid, so thanks for the recommendation! A few more that are near the top for me: Satisfactory and Divinity: Original Sin 1 & 2 (I'll get to Baldur's Gate 3 eventually). Hopefully Cities Skylines 2 and KSP 2 will be able to join this list after some more time in the oven. Also, despite the bugs and Scam Citizen memes, Star Citizen has been steadily moving up my list as updates roll out.

[@dustman96]

I really miss the weekly space hangout!

[@frasercain]

Me too.

[@njaalsturlasson2351]

Perhaps a Q that might be too basic, but here goes: when LIGO detects a collision of two massive objects, e.g. two black holes, illustrations of that event often depict the two objects spiralling into eachother rather than head-on colliding. Shouldn’t that spiralling virtually never happen if the two massive objects preserve the angular momentum vs eachother, i.e. that they just orbit eachother ”forever” instead? If it is a scientifically correct illustration, why doesn’t it happen to the earth and the other planets vs the sun, i.e. why aren’t we similarly spiralling into the sun? Or are we actually spiralling into the sun, but the spiralling is too slow to matter?

[@theOrionsarms]

When two bodies orbit a common center of mass they lose momentum, gravitational wawe transport energy into space and that energy need to come from somewhere(so it's no conservation of momentum for massive bodies if you ignore gravitational wawes energy) , and yes the same thing should happen with planet that orbit sun but much more slower, but also sun is losing mass and become less massive at a faster rate, so actually the planets spiral outward from the sun but also is a slow process, and sun becomes bigger in diameter faster than that process, and also become brighter until would become a red giant star, after that when would become a white dwarf any planet that would orbit it would spiral inward but also would be a very slow process, because of smaller masses implyed and relatively large orbital distances.

[@njaalsturlasson2351]

@@theOrionsarms Thank you very much for that response. Very clear!😃

[@savethedave]

Is it possible that a large near Earth asteroid could hit us but only cause relatively minor damage? I mean if one is travelling in the same orbit with the same direction and about the same velocity, isn't a "soft landing" scenario possible?

[@jamesdubben3687]

Vedikar. Hey, comment bellow. could be copy pasted here. In fact I'll go give it a thumbs up.

[@peters616]

There's a paper published by Dr. Pavel Kroupa asserting the dark matter halos around galaxies have been falsified to a 5 sigma confidence. It's from 2012, called The Dark Matter Crisis: Falsification of the Current Standard Model of Cosmology. I looked it and it seemed well reasoned and based on good data but I don't have a PhD in Astrophysics so I'm not qualified to make an informed evaluation of it. The way I understood it is that he found that observed interactions between galaxies preclude the presence of a dark matter halo, because such halos would cause a friction-like effect that would slow visible matter movement when galaxies interact, but that effect is not present in the observed data. Dr. Kroupa seems to be a well-respected Astrophysics professor at the University of Bonn where he leads the research group on stellar populations and dynamics and I have not found anything that discredited his work.

[@frasercain]

You will often get single researchers go against the consensus. And that's great, it's how conversations get started. But it's been 11 years since that paper came out, has the evidence grown since then?

[@peters616]

He supports Milgrom's MOND theory and I have seen some more recent work from that faction, including I believe a paper about how gravitational lensing can be fully explained by MOND, and I saw Dr. Kroupa give a more recent interview where he not only stood by his work but also mentioned more on-going work in the area. There are other reasons for the falsification aside from the friction effect, like the cross bars you see in a lot of galaxies would be unstable in the presence of dark matter halos. I've looked for anyone coming out and saying no, this isn't good work because of X and haven't not found that.

[@christopherconkright1317]

I always thought what if dark matter are planets stars etc In a parallel universe near ours. The bending or warping of space allows it to affect our universe. This would explain why we can never see it.

[@jamysmith7891]

Cellular structure requires very specific mechanisms to form, memory too, I think spontaneous brains belong in the impossible pile, most stone is a complex structure for that matter

[@denmaroca2584]

They may be complex, but only finitely so. They have an extremely tiny probability of spontaneously coming into existence, but given infinite spacetime even events with extremely tiny probabilities will occur (in fact, an infinite number of times).

[@cookiexcrumbs]

Q: if nothing travels faster than the speed of light, but gravity traps light, does that mean if we could one day work out how to harness gravity or anti-gravity that we could move faster than the speed of light/time travel?

[@davidbailey453]

Ok Fraser, I have a question for you. Is there a super massive black hole at the centre of the Andromeda galaxy? And if so how come we are not able to view it with the Event Horizon telescope array? I recently heard the only two we could observe were our very own in the milky way and m87 which is in Scotland somewhere (,,joke)

[@douglaswilkinson5700]

There is a SMBH at the center of M31. It's estimated to be 100M solar masses.

[@bjornfeuerbacher5514]

The Andromeda galaxy is way closer to us than M87, yes. But on the other hand, the supermassive black hole there is much smaller than the one in M87. That's why it's not that easy to see it.

[@frasercain]

M87 and SgrA* are the two largest black hole event horizons we can see. Everything else is visually smaller, which is why you have to go to space to extend the size of the EHT.

[@davidbailey453]

@@frasercain thanks

[@ryanschmitz3198]

I vote Aeturen!

[@rowlflikes944]

Instead of dark matter is it possible that the universe is drawn together by some sort of electricity the same with dark energy- could it also be related to electricity?

[@desmond-hawkins]

Many software systems involved in piloting spacecraft _are_ already autonomous. They're not called "AI" because that's just branding, but it's pretty much what they are. As mentioned the EDL vehicle that carried the Perseverance rover made its own piloting decisions based on maps of Mars and its live position updated from cameras and sensors. You can call it an autonomous system or AI, either way it's making reasoned decisions based on complex inputs. What's less used is neural networks, mostly because of the unpredictable edge cases it can hit.

[@pepe6666]

cool i didnt know you did videos with sqort manly. he's awesome

[@kristinehansen.]

Do venus have auroras? How do they look like and what causes them?

[@terminusest5902]

When did dark matter and energy begin.? Were they in the early big bang and what effect did they have?

[@frasercain]

They seem present at the cosmic microwave background, which was 380,000 years after the Big Bang.

[@MDCB1]

GOOD!!!

[@arcradious2302]

If matter simply follows the curve of space then why can't it go away from mass. If gravity is not a force why does it have a preference towards mass

[@jasonracey9600]

Does AI in video games make decisions you would trust your expensive spaceship with?

[@jonbbbb]

Keep in mind that in most video games the AI's decision making strength isn't a priority compared to graphics. Now, if you're talking about a game where the AI is the priority then absolutely. If for some reason your life depended on a chess game, you would be insane to let a person play for you instead of a chess AI.

[@rowlflikes944]

At the point in time when the moon breaks away from the earth is there any danger of it eventually colliding with the earth?