Q&A 51: Could We See Ourselves in the Past? And more..
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- Опубликовано: 28 мар 2018
- In this week's QA, I wonder if we could use the speed of light to see ourselves in the past, how the Mars rovers clean their solar panels, and if aliens would infect us with their bacteria and viruses.
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Team: Fraser Cain - @fcain / frasercain@gmail.com
Karla Thompson - @karlaii / / @karlathompson001
Chad Weber - weber.chad@gmail.com
Chloe Cain - Instagram: @chloegwen2001
Balázs Suhajda
Hi Fraser! We use massive cosmic bodies to bend light and magnify distant objects, soon using them to observe exoplanets and their atmospheres as they were long ago. I wonder if it could be possible to find rays of light that have left earth long ago and through the curvature of space end up returning to earth with high enough resolution to allow us to look back into the past. Is it completely out of the question?
path finder discovery
I want to know who dusts off the solor panels when it gets dusty an it probably does often due to those huge dust storms , hmmmmmm🤔??🙃🤓🤔🙄 ohh👽👾😱😨😍
Schnitzel Vonlichenmenutz
Imagine the virus’s and bacteria they may unintentionally bring. Could potentially be the end of all life on earth. Also, I hope they have a good immune system for our planetary virus’s and bacteria
Alpha Gusta
I notice that in some space launches that the space craft immediately starts to spin into another direction, I know some course correction is needed for different orbital planes and trajectories. But sometimes it seems like they turn 90 degrees.
Why dont they just build launch platforms in somewhat the correct direction?
Phil Metal
When the galaxies merge or slam together, would it be a slow event until things start smashing into each other? Or would some crazy gravity changes rip world's apart and it be a cataclysmic show? In your opinion would it be a galactic reset, would anything survive
CODELESS
Enjoy your videos and Q & A's : i was wondering, with this Mission of colonizing mars in the future, there are some ideas that the domes could have water in them to shield Radiation. How much water is needed to block radiation as in the thickness or width of water to block radiation. Thanks
XXCoder
I was wondering if it was possible to make "bed cylinders" that is partitioned into 2 sleeping areas. With some automatic counterbalancing for mass differences, it may be enough for sleeping in gravity for better health?
Jim Labbe
If super earths are more massive and have greater gravity wells, might that make space travel much more difficult for intelligent life? Put differently, if we could increase the mass of the earth at what point might it create a physical constraint on space travel?
Captain Ultimate
G'day from Down Under! I am a new subscriber and I am really enjoy your videos Fraser, so thanks for your knowledge and all your hard work. Would there be any point or benefit to launching a telescope into orbit around a planet in the outer solar system like neptune, or even pluto? Or are they too close in regards to current telescopes to really return any befit?
Matthew Kramer
Hello Fraser, quick question: How do you think our advances in Machine Learning, Reinforcement Learning and A.I in general will affect space missions in the near and distant future? Greetings Matthew
Jesse Dyball
Could you get two BFRs joined by long cables and have them spin?
Peter Granzeier
Do white dwarves have habitable zones? 
Наука
*I was kind of shocked while watching the movie 'déjà vu' when the FBI agent says something like 'when you look to a mirror, you are looking to the past, an old version of you, as it takes some time for the light to reflect you into the mirror and your brain process that info'*
Well technically thats true but the light delay is only like 7 nanoseconds, far too quick for a human to appreciate. Still, that is a good reminder that everything we perceive is limited by our senses.
Yup, there's the time from the speed of light, and then the time for your neurons to fire.
Everything we see, occurred in the past.... The average reaction time for humans is 0.25 seconds to a visual stimulus ... that is the time delay for your brain to process visual input and then construct the virtual reality in our brains that we perceive as reality. If ya have Amazon Prime . watch this neat series that explains this....
The Brain with David Eagleman Link: a.co/iO8L7n
Yes guys, we (our sense of self as derived by our senses) live in the past.
The Exoplanets Channel 80 milliseconds for the brain to process info and less than 7 nanoseconds for light to reflect to you about a meter away from your mirror.
Of course, aliens might still put up giant space mirrors as a courtesy to other species so that they can study their own past ;)
That would be thoughtful of them.
"Terrified. Horrified. Love." So true.
Isn't it always?
Thank you for answering my question! Great channel you've got there :)
Thanks for asking it.
Just found your channel, so interesting! Thanks for sharing.
Thanks a lot, welcome aboard.
keep up the good work Fraser, greetings from Portugal!
Thanks a lot!
Really enjoy these videos, look forward to them every week. Usually don’t comment, just had to say good job and keep it up! You’ve taught me a lot
Thanks a lot, I really appreciate it.
Thanks for answering my question, love the channel.
No problem, great questions. :-)
Fraser Cain do you think, with the likely hood that the first few Mars colonization missions will be 1 way trips and probably end with lost life, will they pull the plug? Or call it a necessary evil due to the nature of exploration.
I don't think they'll pull the plug, once there are people there, they'll need to keep sending more supplies, so I don't think they'll abandon the Mars colony unless everyone dies.
I love your efforts to pronounce some of the names people have, that and the smiley faces :~) What's the most difficult name you've had to pronounce, in the fields of study or peoples names.
I struggle with them all equally. I ruin all the names with my hilarious Canadian accent.
Another awesome video, Fraser!
Thanks!
hi Fraser,Love all the effort you and your team put in. I’d like to know....You always have a down to earth, happy and nice persona about you.How do you stay so positive?
I was probably just born that way. :-) Actually, my Mom set a really good example for me, I think. Always positive and kind to everyone she ever interacted with.
You reading the emojis made me laugh so hard... :D
I thought that was fun. :-)
This is one of my most favourite space channels.
Thanks a lot!
RPKVids WOW, I literally watch your cubing vids!
Lol!
Your answer about the rocket launches explains a gravity turn, but reading the question I believe what it was asking about was the roll program, given they were talking about the angle of the launch pad.
To try to answer what I believe the question means: It is connected, of course. The roll is to line up the craft so the guidance computers can make gravity turn in the correct direction for the target inclination. (It's easier to control the craft with a 'roll to this angle and then pitch down' instead of 'calculate which direction is the correct one and pitch that way', especially when the rockets in question are not straight tubes and have more complicated aerodynamic profiles.)
The reason some rockets need to roll so far, really, has to do with using new designs on old launch pads. For example, the space shuttle had to basically sit backwards on a launch pad designed for a Saturn V. (The roll in that case was also so that the antennas on the shuttle would face the earth.) Building a new launch pad would, however, be far too expensive and complicated just to skip a process that takes a few seconds at most.
At least, that's my understanding. :-)
I thought that might also be the case, but then asking why they don't just point it at the place they're trying to go was what made me answer it that way.
QnA:
How do we know that the Andromeda galaxy still exists if it takes millions of years for it's light to reach us?
Thanks for another great video, Fraser!
I too highly recommend Kerbal Space Program. I learned tons about orbital dynamics... gravity turns, orbit inclination, catching up by lowering your orbit or raising your orbit to fall back, Hohmann Transfers, landing on Mun.
I learned more about orbital mechanics by playing KSP than I did from reporting on spaceflight for more than a decade.
I put KSP on my dinosaur computer and it locked up. Not the game, the computer. It did look interesting as it installed though. No, it's not a TRS-80. LOL
Universe Sandbox 2 is another great space physics simulator.
It does lead to people having unrealistic expectations about sstos though.
Space telescope at Pluto: actually anywhere but in LEO would be a huge benefit. Hubble is hobbled by being right next to Earth blocking half the sky at all times and blinding it with reflected light. And IR observations are seriously undermined by Earth's glow. Hard to beat the servicability of Hubble though.
Yeah, that's why JWST is going to be so far away. But as you said, the serviceability is an issue.
Thank you! It sounds like it would be super awesome to visit a planet in the habitable zone of a white dwarf star! I wonder what it would look like.
So astronomers have found the first galaxy that doesn't contain any darkmatter. My question here is, how do the astronomers determine if a galaxy has darkmatter or not since you can't directly see it. How do we know that that particular galaxy has no darkmatter
They tracked the movements of globular clusters in the galaxy and determined that it's only the mass of just the stars that's pulling them around.
We cant "see" air but we can detect its effects.
Good stuff Fraser. ;O)-
Thanks!
I like the idea of the spinning BFR's... I'd imagine you'd need to do a few modifications, such as hardening the structure to support the different loads, perhaps an add-on harness which can be assembled in space? You'd also probably want to mechanically dampen the vibrations of the cable.
Station keeping burns may also be needed to maintain the correct angular momentum, and also things could get really scary if there was an engine or power failure.
5:06 I think he is referring to the roll program that for example the space shuttle did? Launchpad is already build so the rocket, if orientation matters, has to roll shortly after launch.
I considered that, but it didn't exactly match the question
Frasier is the man!!!
Thanks!
@Fraiser Cain: Awesome show by the way. Star SO-2 was recently been confirmed single and able to prove (or not who knows) Einstein's theory when it zips around Sagitarius A. Will you make a dedicated show on this topic when it happens?
Thanks again for the hard work and informations you give us on a regular basis.
Cheers
Thanks! I'll definitely do a video on Sgr A* and the stuff around it. Especially since astronomers just discovered 10,000 black holes at the galactic core.
I think the rocket question was about "roll programs" executed just off the pad. Hence "Why don't they just build launch platforms in somewhat the correct direction". I believe the answer is that they would like to, but a.) different launches require different directions, and b.) they're also constrained by the infrastructure that moves the rocket to the pad.
I did consider that possibility, but it really seemed like they were wondering why they don't just shoot the rocket at the destination, instead of doing a big turn. But maybe they'll clarify it.
He just got done talking about parasites at 5:00, and then he had a mosquito land on top of his head at 5:01
Who evolved in an arms race with us. This one had the edge on me.
Hi! From Israel here. First of all, this is a fantastic channel. My question - If living on a planet with higher gravity makes space-faring super difficult, what about a planet with lower gravity? what is the theoretical lowest amount of gravity (due to planet size/mass) acceptable for sustaining life? And how would that affect space launches from that planet?
We don't know what the lowest gravity would be, especially if you evolved in it. But for humans, we can't perform tasks or walk around if it gets lower than about 20% gravity. But I'd assume you could have much much lower gravity. The problem is that a lower gravity world would have trouble holding onto its atmosphere.
KSP is in Humble Bundle now. Go get it! :D
I saw that. I'm signed up to the Monthly Bundle, so I'll have a spare copy to give away. :-)
5:10 I think the question may have been about the rotation of the rocket, not the direction of travel. The rotation is because the rocket needs to turn in the direction that it needs to travel. It is way easier to rotate the rocket after launch than to make a launch platform that can rotate.
I considered that, but it really seemed like they were wondering why the rocket doesn't just go straight up to the target. If they do a followup I'll get more info.
I think you missed the point of the "why do rockets turn? " question. It wasn't "Why do rockets pitch over to more horizontal flight after launch?" It was "Why do some rockets have to roll before they begin to pitch over? Why not just have them start out on the launch pad in the correct orientation to begin their pitch over without having to roll first?"
Maybe, and I considered that too, but it didn't seem like that was the question. Maybe they'll clarify their question again and I can answer this other interpretation.
Hey Fraser. The atmosphere is one of the most energy consuming parts of a travel into space. Why don't we build launchpads on top of a massive balloon and start our rockets from the edge of the atmosphere? If the pads were reusable and technically advanced enough, couldn't we basically ditch the first stage on every flight or have increadibly massive payloads?
That's definitely been considered, it's just that there are a lot of moving parts, to build the launch platform and coordinate the launch from it. The reusable approach that SpaceX is taking seems to be the simplist.
If all the scientists are right in that everything in the universe is made of the same "stuff", it would stand to reason that viruses and bacteria in distant places evolve similarly. The environment plays the determining factor. So anything we might encounter could be scientifically broke down if we take into account the absolute utmost of extreme conditions the viruses and bacteria could have come from. That's taking extreme scientific to the next level, AND assuming we really understand what's out there entirely... Having said that - long live the explorer minded.
We'd assume they're made of the same basic building blocks, but we don't know if life on other worlds would even come up with the concept of DNA, or it would have some other way to replicate.
I get it. In a way I like the fact we don't quite grasp many, many things. Keeps a sense of wonder alive, and the possibilities out of our calculations.
We did a video on this topic here: ruclips.net/video/fuo3vWtSdqY/видео.html&index=193&list=PLbJ42wpShvml6Eg22WjWAR-6QUufHFh2v
Hey Fraser, you said that we're close to the limit where rockets make sense, because above that "it's just not worth it anymore". Sure there are limits with gravity x100, but a couple times gravity would still be ok if you're drive to go to space, e. g. because you run out of space on your planet. Going to space for exploring is nice, but the long term goal is to get more space for people to live in. Someone coming from a planet with gravity x0.5 could say the same about our planet. So: The limit is where you can't physically achieve it anymore.
Right, and as I mentioned in the video, you'd need the mass of your entire planet to be rocket fuel to get you to space with 10g. So, just decide when it's too expensive.
I never get why someone downvotes.
Always good explanations on this channel.
They hate questions or maybe answers? Perhaps they hate both.
Fraser Cain or mayby they dont like the answer they got. Anyways good video keep up the good work! Anyone dont agree with any video should leave a comment so a dialoge can be started instead of a dumb downvote
That would be awesome, if people want to have an actual dialog, I'm happy to answer.
Thanks for the info. Guess we will just have to wait for one of those beautiful sun shades that nasa is working on 🌞
Yeah, those will help. ;-)
Hey Fraser great show as always. Im relatively new to the channel but i was wondering if youve ever talked about using different forms of stasis for manned interplanetary travel or even travel to other stars. My though process was if we mastered a form of stasis that also stopped or slowed ageing, then a small spinning centrifuge within a ship could provide enough gravity for the passengers. Also laying down would solve the problem of a centrifuge having more gravity and your feet than your head.
We talked about hibernation in this video: ruclips.net/video/VfmOnqh9vyA/видео.html&list=PLbJ42wpShvml6Eg22WjWAR-6QUufHFh2v
Hey, Fraser! About spacex BFR to Mars and BACK: What about how much water will be needed to make metane there and how much is available on Mars now? I mean it will be like a "fossil fuel" there. Won't water be a too valuable resource for the locals to be used in a returning ship?
It will be a valuable resource, but there are huge polar ice caps. Being able to return from Mars will also be a valuable resource, so they'll need to conserve the water.
I've always envisioned a bunch of BFR style launches to send massive water tanks into space. They are then attached to a central cylindrical habitat module to provide both fresh water and protection from radiation. Bonus points if the entire structure rotates to provide artificial gravity. 🚀
Regarding the recent discovery of a galaxy with no or almost no dark matter. I read that they calculate the amount of dark matter based on the gravitational pole of the galaxy. and they know that based on the mass expected of the galaxy calculated by how far and bright the galaxy is. my question is simple .. how do we know a galaxy is far and brighter instead of it being near and dimmer! .. sometimes I feel lots of the announced discoveries about distant galaxies/stars are based on mere guesses!
Hi Fraser, thanks for all the work you and your team do on these videos. Question for you Fraser, do know what the practical weight limit is for putting things into orbit is? I was playing some Kerbal Space Program with the kids and we were curious how much an IRL Kerbal-style monstrosity could put into orbit if the cost and efficiency was not a factor. I know the rocket equation gives you diminishing returns as the weight of the rocket increases but is there actually a physical limit to the potential size of a rocket? Keep up the great work!
Hi Fraser,
My understanding is that dark matter tends to form a "halo" around galaxies, rather than being the same shape as the visible galaxy. Two questions:
1) if I'm wrong about that, can you explain how we think it is distributed?2) what does the distribution of dark matter in and around galaxies suggest about its characteristics?
Hi Fraser! I've wondered a long time if we could use entangled particles to create interstellar communications? that way we wouldn't be bound by the speed of light or any limit, it'd be instantenous!
Unfortunately you can't do that. You still need to communicate the state of each particle at regular speed.
I now realize that this means aliens are going to see me in that idiotic hot pink baseball cap I wore in the eighties! God damn it......
Only ones that are about 30 light-years from here.
Talking about pests at 4:55 a mosquito landed on your head 😂
Yeah, or a simulated mosquito...
Hey Fraser! Thanks to all the work you and RUclipsrs like you do, I feel like I have a much better grasp of space and to some extent Cosmology. That said it's been a bit since I've had my mind blown by some new fact. I think I'm ready to delve into materials that would be hard to cover on RUclips, but I don't think I'm ready for hardcore scientific journals. Do you know of any good "middle ground" resources? Thanks!
I try to attach those middle-ground videos as playlists to the end of all Guide to Space videos I do. I really like Starts With a Bang blog as more of a challenge. medium.com/starts-with-a-bang
And then, of course, there are books.
But you might also want to try some journals, they're not that bad. Start here: arxiv.org/list/astro-ph/new
Ooh, and astrobites: astrobites.org/
I just watched a video from the Goddard Center about a galaxy that seems to have an unusually low amount of dark matter. In it, the presenter talks about "ultra-diffuse galaxies," and it got me wondering: what exactly is the definition of a galaxy and how do we identify these ultra-diffuse things as such?
They've only found one of these so far, so I'm not sure it's a category yet. Diffuse just by not having a lot of stuff in it.
thanks for the great videos!
its a pleasure to support your channel on Patreon, recommend all to do it!
What is the fastest growing business for space? I mean not Spacex directly, but its suppliers/partners?
What education should i get to increase my chances to be part of space work?
From Wikipedia on the this subject: "The subsequent lifetime of white dwarfs is thought to be on the order of the lifetime of the proton, known to be at least 10^34-10^35 years". Did you hear you said 3 x 10^9 years?
No, I think I said that was how long it would take for them to cool down, not for how long it would take for them to decay.
Fair enough, I didn't read that as decay time (but a half-life). But from Wikipedia for Schools: "...few white dwarfs are observed with surface temperatures below 4,000 K, and one of the coolest so far observed, WD 0346+246, has a surface temperature of approximately 3,900 K. The reason for this is that, as the Universe's age is finite, there has not been time for white dwarfs to cool down below this temperature. The white dwarf luminosity function can therefore be used to find the time when stars started to form in a region; an estimate for the age of the Galactic disk found in this way is 8 billion years." Other sources as well state that no white dwarf has cooled down in the 13.8 billion herstory of this local universe. That said, you are still the best podcaster in this Solar System. And so responsive!
To understand how getting shit in orbit works, play kerbal :)
All hail KSP. I've learned more about orbital mechanics from that game than I have from decades of being a space journalist.
I have a question. Was is there any research done on behaviour of flying birds in microgravity? I can't seem to find anything relating to this. One would expect this to be a major area of study, since study of bird flight has close relationship to aeronautics.
Great as always. Question: if you use water to shield from radiation... can you use that water for drinking?
Fraser - lets say in an alternate universe, the governments of the world spent the same amount on space exploration as we do on on our military. The US alone will spend $886B in 2018 (declared budget); what can NASA do with that kind of money? will we only explore our solar system quicker and still never reach the stars?
Just multiply everything you see from NASA by about 40. 40 missions for every one mission we have today. It boggles the mind.
Hello Frazier been watching your channel for a long and it's wonderful. I love the other RUclipsrs that you suggested. Now I would like to get into this I've been interested in science for over 20 years now physics mainly cosmology and I'm getting into astronomy a whole lot more now my question is I want to start making RUclips videos with what I've learned mainly for my son in case something happens to me if it takes off great but if something was to ever happen to me I would like him to have some of the knowledge that or what I feel is knowledge locked up in this old head of mine and I figured this was a good format cuz it will never go away. What I want to know is what's a good starting camera what's a good starting Mike and how many videos do I need to put back to get content out as quickly as possible. When you started remember you said that you had kind of a well of videos at the beginning that you threw out there all at one time I was just curious. Have a good day sorry it's such a long question keep it up we need to get all this knowledge out to as many as we can.
I think the best camera to start with these days is your smart phone. There are lots of RUclipsrs out there who use their phones for both the audio and video.
Hey Fraser, does the New Horizons spacecraft have any instruments on board that could be useful in characterizing the edge of interstellar space, like the plasma and magnetic flux detectors on the Voyager spacecraft?
Well, I was just thinking about the long distant traveler, Voyager.
I know it recently made one of its last maneuvers, what would that maneuver look like if one were to be sitting next to it. Would it be now a maneuver in total darkness? Could you even see the cray at all? I am assuming the engines were using a compressed gas such as nitrogen or some large molecule gas (to help prevent long term leakage; hydrogen would surely escape).
If the engines use gas, it must be so cold that the gas must be in liquid form and heated by the craft to work. Would you not see the gas released? Or is there ignition?
I once spoke to a retired JPL engineer who worked on one of these deep space craft. He said the craft was worked on in a room which was in a room which was in another room to prevent contamination of every possible type. Magnetic, dust, etc.
Thanks, love the videos.
Thanks a lot. The spacecraft has thrusters that it can fire to change its orientation. If you were beside it, you'd see a puff of gas come out from its thrusters.
Hi Fraser, I just love your programs. Thank you so much! I'm not that knowledgeable about physics, so I have a question. Why was it so difficult for space agencies to pinpoint more precisely when and where Tiangong-1 would come down?
There are just too many factors involved. The thickness and density of the atmosphere, the way the space station was tumbling. All of that would change the entry location.
Can you give a bit more detail?
Which part? Stand in a strong wind with a piece of cardboard. Hold it face on to the wind, and then hold it edge on to the wind and feel the difference in the force you experience.
Hi Fraser, I've got a question for you.
Would it be possible to explain the very fast rotating galaxies by a huge number of supermassive black holes or even by something that is more massive than the most massive known black holes and would cause different effects?
2:07
that was so funny ! xD
we love u fraser ! :)
Thanks!
Fraser the emoji pro lol :)
HI Fraser, I like your channel a lot. I have a question. What will happen to Jupiter when it stops being active? Will it loose it's atmosphere? will there be a surface? What will it look like? Greetings Lesley.
Q&A: Comments on the recently observed visible-matter-only galaxy?
We talked about it last night in the Weekly Space Hangout: ruclips.net/video/-29Osmm7PQI/видео.html
Hi Fraser, I'm not sure if you've covered this yet (you've done so much already!). if we can measure the gravitational waves or colliding neutron stars, why can't we use precise gravitational measurements to detect/prove the existence of Planet X?
We can only use gravitational waves to detect the most extreme events in the Universe, like colliding black holes and neutron stars.
thank you for reading the emojis
Hey! I was wondering, are the theoretical Roche Worlds actually possible? Thanks!
The idea is cool, but I can't imagine a way that it would actually be stable. Forward is a smart guy though, so maybe he's done the math.
Hey Fraser love the show!
Question: What is the purpose of all the smoke on rockets (and underneath them) some time before the launch to space. Is it for cooling? Also, why is the fire exhaust on a rocket getting wider after some time when the rocket is climbing? I hope you know what I meant. I'm not an english speaker... Greetings from Croatia!
Thanks
Thanks! That's actually water vapor from the huge pools underneath rockets. These pools dampen the sound and heat from the rockets so they don't tear apart their launch towers.
Hi Frasier, what's your favourite Galaxy from the photographs that have been taken so far?
Fraser, is it possible that there is no dark matter, but a bunch of small black holes all over the universe, influencing moving of everything? Maybe that weird galaxy without dark matter is just too old to have significant number of miniature black holes, or space over there is somehow restrictive for forming of such black holes.
This is one of the possibilities proposed for dark matter, but not many astrophysicists really consider it serious any more.
Hi Fraser. I know you get a lot of questions about Galaxy collisions but if say 2 stars did collide what would be the possible outcomes? A merger, a Supernova or maybe an emerging winner like Earth over Thea? Thanks for your time. Chris
Here's an older video for you: ruclips.net/video/ZucjiKb6IRI/видео.html&index=302&list=PLbJ42wpShvml6Eg22WjWAR-6QUufHFh2v
Hi Fraser, I have a question... if massive objects “warp” space time and affect its curvature does that mean the fabric of space/time has mass? If gravity is a force between 2 objects of mass then how does a massive object affect space unless space itself has mass? How does it pull on it and curve it?
No, it's just that mass bends space and impacts the passage of time. Why? Because that's what it seems to do.
Hey Fraser, if we for a limited number of times could visit any place in the universe , what would our destination priorities be to get maximum amount of science done? What do scientists really want to see up close?
Any place in the Universe? Wow, then they'd want to do close up observations of various objects that we don't have in the Solar System, like brown dwarfs, white dwarfs, neutron stars, magnetars, supernova remnants, etc. Very cool.
Fraser: Are you looking forward to the Dark Souls remaster? Forest Bros 4eva
They're remastering it? Cool, now I'll be able to die to the zombie dragon in stunning HD.
May 25th is the release date!
With all the stars in a galaxy, and all the galaxies in the universe producing so much heat, why is space so cold?
The vast distances involved make the total amount of radiation falling on any one spot so low.
8:30 Are the cops after you Frazier? You can hideout at my house.
Hah, just more noise pollution.
Shielding with water - does this account for ice too? Easier to have ice than water in space, right? (Or perhaps not, but anyways. I read about the idea of ice as a shield for fast space travel to shield from micro-metorites and other debris.)
Yes, ice works the same as liquid water.
Hey Fraiser! I got a question.
Since planet Mercury is the color gray, how come in books they show Mercury as the color brown?
Color depends on what information they're trying to convey, what filters were used, what kind of wavelength of light was captured. Did you see this video? ruclips.net/video/Q41hLHcKyUM/видео.html&list=PLbJ42wpShvml6Eg22WjWAR-6QUufHFh2v
Woh. Watching you stoned af and it looked like your face was coming out of my screen. Trippy.
Hey Fraser! About the water used for radiation shielding: would we be able to use the same water for consumption later? Or would that water be contamined?
No, it'll actually turn into heavy water over time. You don't want to drink that.
I see! But does the heavy water keep working as radiation shielding? Or does it have to be renewed every certain amount of time?
Hello Fraser,Since some white dwarfs and neutron stars have been found to spin at incredible speeds, I was wondering if they may come close to flinging anything off their equator, or even cancelling a significant fraction of their own tremendous gravity at the surface. Is this even possible within our laws of physics?
Neutron stars can't, but white dwarfs can spin so fast they can have an early death. Check this out: www.newscientist.com/article/dn23282-astrophile-dizzy-dwarf-star-will-spin-itself-to-death/
When talking about galaxies colliding, all the experts point out that there is almost no chance of the stars hitting each other. That is fine, but the solar system is 3-4 light years across. The star systems are going to "hit" each other at high speed repeatedly. Yes, the systems are mostly empty space, and actual collisions of objects are unlikely. But gravity is going to send comets, and possable larger objects off on crazy orbits. I expect the results would be as bad as, or worse than the late heavy bombardment. As the galaxies pass through each other, this is going to happen many times to every star system. Thus, I think it is likely colliding galaxies will wipe out most if not all life in both galaxies. This could be a partial explination of the Fermi Paradox.
When galaxies collide you get a flurry of star formation, you get gravitational interactions between stars causing increased comets, asteroids, etc. But you don't actually get stars smacking directly into each other.
John Bennett , if it's not a "great filter", it could well be a "biggy".
If you could make your way to the edge of the expanding universe, probably meaning that you'd have to be travelling at faster than the speed of light, and you looked back with some high tech equipment, theoretically should you be able to "see" everything that has ever happened? Or like you said, can some "photon info" get lost through things like black holes?
hello Fraser. Idont know if this even is a viable question and i dont fully understand entanglement but if u could make some kind of instrument that was entangled with something (i think the same instrument) in our end could we send it in a Black hole and still get information. sum up is... does a black hole present a boundery to entangled particels like Things that is bound by gravity. Is there theroies about that or is it a silly question.
No, the problem with entanglement is that you still need to communicate the results of your entanglement, so you can't get the signals out of the black hole.
but how ecatly does entangled particles communicate. spooky action at a distance as one guy said. what makes the barrier then.
Quick question: on any future colony on mars would it reach the stage where many animals are transported their to provide food for example
I'm not sure we'll ever see cows on Mars, for example, we're probably going to be seeing cultured meat that's grown.
2:24 cracked me up. What a guy! Keep doing what you do Fraser, I love it!
Thanks. :-)
Consider this... Since SpaceX contracts with NASA to take humans to the ISS I understand the government requiring the Dragon Capsule to be human certified. But nobody owns Mars and SpaceX is a private corporation... To land on Mars you wouldn't think they would need any government' "certification" where there is no governing body. Do you think SpaceX should be required to meet the US government's certifications for the Dragon Capsule (or any other part of the rocket) to take humans to a place like Mars that has no government? My focus here is on the "required" part of it. What do you think?
No, if they're launching to Mars, I don't think they'd require any certification beyond FAA guidelines for protecting the Earth. What happens to them on that journey is up to them.
Hi Fraser,
Great video’s. Is there evidence that Europa has oxygen in the water under the ice? I watched a video about life that lives on thermal vents on earth. they we’re talking about that kind of life is very sensitive to oxygen levels in the water. Since Europa doesn’t have tidal action how likely is to be life on any of the frozen moons in the solar system?
I can't imagine how you'd get oxygenation like we have here on Earth. But there are lifeforms that do okay without oxygen.
Hi Frazer, great video once again.
Regarding the question at 5:05 about the rotation of rocket, I think he was asking about rotation around the rocket's vertical axis. Even if it wasn't, could you please elaborate why do some rockets spin a little bit after the launch?
I'll cover that in a future video, but here's a quick answer: www.popsci.com/why-does-rocket-need-to-roll-going-into-orbit
Fraser Cain Thanks for the link, I'll go through it. :)
I have never seen a story about it, but imagine making technology to save races who are gravitationally locked on their planet. Going around to 2-10 earth mass planets and build space elevators for them. It would be a very good altruistic mission for a future galactic empire.
Is it possible to bind a Muon (the heavy "electron") into a superheavy atom, like the ones at the end of the periodic table??
would it be stable?
Was wondering about the water shielding. Does water or can water get radiation saturated and need to be changed? Or would it just be to simply fill up the "domes" or whatever and forget about it?
Judging from how highly radioactive nuclear waste is treated, sunk into a pool of water, the water shield could probably just stay there.
Great question, I look forward to seeing someone answer this.
Water is used to block radiation for nuclear reactors and it does get more radioactive over time.
Bro Brah , EM radiation stopped by water would just cause some heating (like a microwave oven) and maybe some flourescence too. Those effects would be temporary.
Cosmic rays are actually particles, and if stopped would become suspended in the water, ~ gives it that space flavour.
Hi! I've seen a bunch of pictures where the inner two solar arrays of the ISS look different from the others (example: upload.wikimedia.org/wikipedia/commons/8/80/ISS_March_2009.jpg). I guess this is simply because they are turned by 180°. But why is that a thing? What is the benefit of doing this?
There are the solar arrays and the cooling panels. Is that what you're thinking of?
QUESTIONs. Question regarding warp drives, warping of space in general. If space warps around us, like in a gravity well, do we physically warp with the space ? If we bend with the space, then does our velocity "deform" too ? This all leads to, how can we use bending of space to travel faster ? And if we do not deform with space, how would a collision with the walls of a wormhole would look like, when the borders (as i understand )are, heavily deformed space ?
well, yes and no. If you have group of particles that experience no attractive/repulsive forces to each other (like particles of neutral gas), then yes, the relative positions of the particles will warp with the space. However, if you have particles bound with forces to each other, then the attractive/repulsive forces will respond to the changing relative position of the particles.
Example, let's say you are in space and you are standing knee deep in some weird space anomaly that is contracting on the inside, but has absolutely no effect on the outside. You would feel a force pushing on your feet, while the rest of your body experieces weightlessness. Similar to how when you're standing knee deep in water, the water squeezes on your feet.
Hey, Fraiser! What if we find a way to create antimatter with greater than 50% efficiency? Aren't we gaining profit from annihilating it then, just because regular matter also annihilates, and we didn't create that, it was just sitting there all along before being turned into energy. Is that possible?
Hi, Fraser. Exo planets are so hard for us to detect... is it possible 'dark matter' is planets? And how many planets would each star need on avg for that to be the case?
...I think Ive answered my own question... my limited knowledge suggests each star would need thousands of planets... haha...
If we had 1,5 g then getting to orbit would be about as difficult as launching something towards Mars, if we had 2 g then getting to orbit would be about as difficult as launching something towards Pluto.
I wonder how higher gravity would affect the atmosphere?
zapfanzapfan , we would have more atmosphere, and it would be deeper and more dense.
There would probably be more hydrogen in it too, as it would be harder for H₂ molecules to escape Earth's grasp.
I bet our respiration system would have to get an upgrade for 2G to be comfortable, too... or develop dolphin skin & start living in water full-time to compensate.
Lower gravity would make the atmosphere thicker (stretch further out from the surface), like on Titan, higher gravity would do the opposite I guess. But at some point when the gravity is enough to hold on to helium and hydrogen it will likely get thicker again, question is where that transition happens.
Venus has a denser atmosphere than Earth yet Venus has slightly less gravity than Earth.
Hey Fraiser! I got a question.
Since distant galaxies are moving away from us because of the expansion of space. And, let's say a galaxy 1 Megaparsec away is moving from us at the speed of about 70.6 km/sec.
My Question: Is the expanding space 1 Megaparsec away expanding at 70.6 km/sec, or not? Or, is the distant galaxy the only one moving at that speed and not the expanding space?
yes, and if the galaxy is 2 megaparsecs away, then it's moving at 140 km/sec.
Fraser Cain - But, if a galaxy is moving away from us at (let's say) 70.6 km/sec, does that mean the expanding space is expanding at the speed of 70.6 km/sec?
Would it be possible to make a gravitational push on the entire solar system in order to use the entire system to move across space in a specific direction, say, close enough to another star?
Like a ginormous interstellar motorhome.
Miguel Akira , Shkadov engine
You move your star, and your planetary system goes along with it.
Here's a video we did about that: ruclips.net/video/YFmj-0atHdk/видео.html
Hey fraser a kinda weird question i was thinking what would happen if you compress earth down to its Schwarzschild radius but it were to spin so fast that its just out of this zone... and what would happen if it just slowed down JUST slightly to the point where it collapse would there be some sort of epic boom or would it just collapse and become a normal black hole? (Kinda of a weird question but hey xD)
If you compressed the Earth down to become a black hole, essentially, and then spun it up, you wouldn't be able to reveal it again. The maximum speed you could spin it would be less than the speed of light, and it would take an infinite amount of energy to spin it faster and faster.
Hey Fraser, I was just thinking about supernovae, like ya do, and I was wondering: is it true that stars don't create *any* heavier-than-iron elements unless they go supernova? Or is it possible that there is a relatively small amount created during a large star's normal lifecycle? I can imagine that maybe here and there a few iron or nickel ions get a little extra kick from some nearby fusion reaction, enough to make them fuse. Is that possible?
Right, you can only get elements heavier than iron in a supernova, and now it looks like you can with colliding neutron stars.
Hi Fraser, I wonder: Does centrifugal force, made by Earth's (or other planet's, asteroid's etc.) rotation, counters or affects gravity in some way?
Higher gravity means we couldn't rely on rockets alone. For example we could use a gun and a small rocket. WW2 Germany planned a gun like that for artillery/bombing Britain.