10:22 This is why Expanse is *the best* at hard sci-fi. When the ship is en route they spend half the time accelerating and half the time in decel flying "backwards" and therefore the ships are structured vertically like towers and not lengthwise like maritime vessels while for space stations they simply use spin gravity. And additionally, this is why LDSS Nauvoo looks like a barrel. It is essentially designed to be a space station tumbling through interstellar space at no acceleration through most of it 100 year journey, therefore it is designed to be spun up as it stops accelerating.
Replying to first paragraph - you don't need to read a lot of scifi to get that. In revelation space series, it's just that way by assumption. Like the author doesn't need to explain it he's like yeah of course that's how it works.
Yeah the Nauvoo is a typical cylindrical ship design, those go all the way back to rendezvous with rama like decades and decades ago. Probably before that.
@@ericv738 Neither does the Expanse (at least it's not emphasized), and whaddayaknow sadly many people, even fans, miss this fact. The difference is that the other ones are books and none of them had a popular and carefully crafted and engaging TV show made after it meaning this kind of sci-fi was "locked" to only dedicated sci-fi fans and bookworms, while Expanse started to introduce the hard sci-fi concept, in a very fluid and engaging manner, to the broader audience, which is a very good thing.
My problem with constant acceleration under rocket power is that it is described as being in the jaws of a terrier. Question: Is it a lot smoother once out of the atmosphere?
Really enjoyed the video Frasier, thanks. One thing I wish you had mentioned when discussing using tethers for an artificial gravity system is that due to the compact storage and light weight of a tether system compared to a rigid structure the ability for tethers to extend the diameter of the rotating mass well beyond what is possible with a rigid mechanical structure makes a lot of sense. The reason extending the diameter is desirable is what that does to reduce the problems inherent in using rotation to simulate gravity. Rotation simulates gravity fairly well if the structure's diameter is several times the persons height and while the person is stationary within the structure, but when the subject moves strange things happen. There are several videos on this on youtube. Even throwing an object (a ball, etc.) in this situation causes the path of the ball to curve. The anomalies can bring on motion sickness and other issues. These effects are reduced by increasing the diameter of the rotating mass. Most hard structure rotating space stations proposed, even large ones, would suffer from these issues rather significantly. However when using tethers it's not out of the question to use diameters of more than a mile for example. This would make the environment much more tolerable and do a much better job of simulating earth-like gravity. One thing you have in space is, well, a lot of space. Why not take advantage of it?
Glad you finally read Accelerando, it's in my top 5 favorites along with Diamond Age, Quantum Thief, Diaspora, and Incandescence. It was written in 2005 and the predictions would have been more accurate if the Dotcom bubble didn't happen and the optimistic early days of the internet continued to develop.
I just want to say I'm so happy UA-cam recommended your channel to me because I love your channel and love your encouragement to ask questions and for being so courteous and professional even to the trolls. ✌️😎
Voyagers are at about 159 AU right now and it takes some impressive technology to even communicate bytes of information with them at that distance. We'd need communications improvements of several orders of magnitude to be able to download quality image data from a telescope at 500+ AU. I doubt we're anywhere near that right now. Perhaps we'd need some powerful relay probes every 100 AU to pull that off.
I wonder why we didn't launch a pair of voyagers every decade or so.... Could have used relays to extend mission life by multiples, I guess. Also data in depth.
@@dougselby7592 The 500 AU "Sun_lens" Einstein_ring, single_target, disposable telescopes will not slowdown or enter an orbit (they will work until they get too far away from the lens_focus). . Since observing exoplanets in detail requires time (seasonal changes in clouds, dust storms, ocean/forest coloration shifts, etc); multiple identical ones will be sent on regular series (maybe changing the cameras for fine tunning sensitivity to specific color/band absorpion); with the same shape, size & capabilities to constantly replace the previous one. . An RTG can keep the electronics & batteries warm, but to supercool the sensors and send data at high bitrate (compressed, encripted & re-sent multiple times for error correction); even using its replacements as relay in daisu chains... it NEEDS a nuclear reactor. -> Not much "fuel" is necesary (little extra mass for the fission reactor & anciliary batteries, no pumps if using passive dissipation and "pulsed" scheduled power production)
I think any improvements in tech we get will only let us detect their signals for longer, but maybe not improve the bitrate they're transmitting it at I wouldn't think
From the calculations I've see a constant acceleration of 32-feet per second per second for about a month your ship would approach c -- the speed of light.
Yes, but you actually keep on accelerating at 1G forever. You'll never actually reach the speed of light but you'll experience more and more time dilation. You could travel billions of light years in a single human lifetime.
I was trying to hold off, but I’ll be that guy… acktually… From the perspective of a stationary observer, say anyone on Earth, a spacecraft continually accelerating at 1 G will get arbitrarily close to C. From Earth’s perspective the spacecraft will need a minimum of 4.24 years to get to Proxima Centauri. Subjectively the spacecraft could go well beyond C thanks to Lorenz Transformation. Time dilates to make it seem Earthlings are running at 2x or 10x or some-arbitraryX. Distances along the line of acceleration shrink so it won’t feel like Proxima is all that far away on top of getting faster. The downside is the time mismatch between the spacecraft and Earth. The spacecraft could get to Andromeda and back within the lifetime of the astronauts if they could get to 99.99% C. But Earth will be at least 10 million years older than when they left. If humanity hasn’t died out they will have long since forgotten about the astronauts. More likely the astronauts are coming home to a planet ruled by intelligent cockroaches or intelligent octopuses.
@@cancermcaids7688 The acceleration of Earth's gravity is 32-feet per second *squared.* First second is 32', next second 64', next second is 128', etc.
And also… after getting to 80%+ C any small atoms (even in rarified space) you hit are going to hit like hard gamma rays. Gonna need those Larry Niven magnetic monopoles to protect it.
My question: How to decelerate from (near)lightspeed, if we ever be able to travel at lightspeed. The target can be overshoot very easily. And how to avoid collisions with whatever comes into collision with a lightspeed traveling object? You need lightspeed correction capability. BIg fan of your show! Thank you for sharing your content. Best regards from the Netherlands.
Speaking about telescopes I would enjoy knowing someone with a telescope that was happy to show me the night sky. The one evening I had the opportunity years ago viewing Saturn was brilliant. Something about seeing with your own eyes 🤘🇦🇺🌌
Hoth. 1g doesn't seem too much in the short term. But, can you imagine the energy requirements in any real length of time? I thought you did a segment on this a while back where 1g approaches the speed of light... eventually. One G acceleration is a great sci fi topic. I like it.
@@filonin2 Then the acceleration would be reduced also the closer you approach (but don’t reach) the speed of light, due to more and more energy needed to keep accelerating the mass? Maybe I got this wrong, but this is how I understood the physics involved? Have a great day! Br
@@mhult5873 theoretically if there were no other matter in the universe and a had a hyper efficient rocket, you could keep experiencing that 1g acceleration indefinitely. Every time you dropped a marker off the side it would fall away at 1g. Practically, you would eventually run out of fuel, or length contraction would make the imperfect vacuum of space so dense that it would take more and more force to push through so you never reach c relative to the universal center of mass. At any rate, if you were to you reach the escape velocity of the local galaxies, metric expansion would eventually push you past c relative to the starting point
- If the X Y, and Z axis changes in space..? What do you use as reference point? - Gyros in space and its benefits to Human space transport. - The difference in takeoff/landing between Earth and Mars? Even the Moon? I know there is a substantial +/- pull, push = apogee towards thrust, but how can that benefit humans? - What are some of experiments that have been completed on the ISS that have already helped humanity, along with Space Flight? Sorry for the question, just super curious. I have a ton more. Thanks for a great episode. - NOM
Ha...30.34...is space exploration the domain of introverts? As a psychologist and an introvert I know we love working alone/in small groups...I know I would I be happy with a few years of limited interactions with others :)
I used to say no way, but since my life changed so drastically that I have no one that I would miss other than those I can just text and call like I do now, sure, I'd be fine with it. Only thing is, now I'm too old, and I'm disabled, so I'm out of luck. 😂 When I was young and in shape, I'd never be able to do it mentally & emotionally. Now that part won't affect me, but I'd never be able due to fitness and age. 🤷🏽♀️ Now that, as a really old satirical song said, means "if it weren't for bad luck, I'd have no luck at all!" 😂
Sorry, not sure how to ask a question to get it addressed during live podcasts...but, 5.50 shape/size of moon craters....my first question is, when was the most recent 'significant' asteroid collision on the moon that we can detect through modern observations, and second question, do we monitor for potential 'significant' asteroid collision with the moon, for the potential catastrophe being that the moon/its orbit/or debris has the potential to impact the earth?
Question for next show: are there any stars exactly located at the barrier of the observable universe, that we could watch leave the observable universe? if no, is it possible, and what would it look like?
Oh, book recommendations! A favourite of mine is 'Chasing Venus: The Race to Measure the Heavens', by Andrea Wulf It's about the transit of Venus, but it's also about some of the explorers who were attempting to record the transit, and... it's great. Some of the journeys were absolutely mad. I can't recommend it enough. I've lent my copy out several times and I'm always a bit relieved when it eventually comes home 😁
9:20 Assuming you are standing up, if you could measure the difference in gravity between your head and feet then you would know if you were in an elevator where everything is the same or else you're in one of these: on a planet etc or in a centrifuge. I don't know if greater sensitivity would answer which one.
Bespin Just upgraded my AP rig yesterday. I’m all in for building your own rig, but these serve a purpose to make electronically assisted astronomy accessible.
Yup, if youve got the skills and patience, build your own rig. If you just want go outside and see some cool stuff, these automated scopes are the way to go. Especially if you're rich.
Alderaan. Have to see Stowaway. Robert Zubrin has mentioned having a tether between the spacecraft and the upper stage as a strategy to combat the effects of weightlessness on the way to Mars.
I will admit the snarkiness was not very nice. But the question was earnest,...how do "they", whoever they is, determine so much information from a light dot on a slide? It's a legitimate question that believers of science dogma refuse to stop and ask. The scientific method requires empirical evidence that can be physically demonstrated. Hypothesizing what light dots are on a space telescope slide is NOT demonstrable evidence; therefore no scientific method has been used to determine the answer to the question.
@@stephaniemcguire I respectfully disagree. The first step of the Scientific Method is formulating a hypothesis (or a guess, as it were). The ones saying the dot breaks the big bang theory are in fact the ones not participating in the scientific process.
@@nandesu I've made no references to big bang at all. I'm referring to a description of a light dot hypothesized to be a planet with certain presumptions made about it as if they were real.
The goal when answering those types of questions aren’t to change their minds. It’s to explain what’s happening to those listening in who are unsure/undecided. It’s to educate those on the fence that genuinely wonder how things like this work, and to educate those who do trust the science but might not know how a specific things works.
Fraser, I have a question about gravitational waves. If they distort both space and time, then why do we not use an array of atomic clocks to look for the time distortion as the waves pass? Instead, we use lasers to look for spacial distortion. Is it even possible?
question: for artificial gravity, is there any advantage to a big wheel instead of having two capsules linked by a tether? the latter sounds easier to pull off and easier to scale up. i imagine for a Mars mission you could have two starships connected nose to nose by a tether, one for the crew and one with supplies needed on Mars
Hey Fraser, this is a two-part question regarding the ISS. What would you say are the top three discoveries made from the ISS? At this point, what was the last main discovery made from the ISS, basically, in your opinion, is it still worth us? Keep it around when that money can be allocated somewhere else? Thanks, Jason
The problem with linear acceleration can be summarized simply as this. Accelerating at 1g for one year without lorenze correction is c. The rocket equation is dV = Ve * ln (Mi / Mf) where Ve = exhaust velocity, Mi = initial mass, Mf = final mass of fuel. if t = dV / 9.8 and Ve = ISP * 9.8 then t (@9.8) = ISP ln (Mi/Mf). Mi/Mf is typically 3 to 4 and so natural log (2.68) of this is roughly 1. But because the mass decreases acceleration increases to 3 or 4 g. If we take the simple average it comes out to be about 3 * ISP. 😅 ISPs range from about 200 for hyperglolics and 460 for SSME H2/O2. So for traditional fuels runtimes at one g are between 400 to 1500 seconds (25 minutes) For nuclear thermal rockets you could double or triple that. For Ion drives there is no limit to ISP (OK, limit is C/9.8), and this is good because it spares fuel mass, but theres a problem. And its going to go back to the initial summarization Suppose we wanted to accelerate for 1 year. So we want Ve in roughly the 1 x 10E8 meters per second. So lets say we want an ion drive to do this. Our ship weighs 10 tons. We need 9.8 m/s newtons. So 9.8 x 10,000 kg = 98,000 Newtons The ion drive equation is Force = Power x Efficeincy / Ve So 98000 = Power x 0.85 / 1E8 its something like 10 x 10E12 watts of power. Thats about the power needed to run an entire state. But thats only one problem 1. 15% inefficiency requires a huge mass for dissipating waste heat 2. There is nothing that can generate this level of electric power in space. Currently the ISS requires 14 kg per square meter of panel which deliver about 200 watts per meter. So the answer to the question is more like this, you can generate milli-g of constant force in space constantly (conserving mass with high ISP) but it would be very difficult to get into the integer range of acceleration. But if we think about the problem like this. If we could sustain a constant 1 g acceleration you could accelerate halfway to mars in a few hours, reverse acceleration and land in the same day. We would not need artificial gravity. The problem in space is this, where is the energy? If you dont have a great source of energy, you not going to be able to do alot of things.
That was what i quickly found out after i made a 15" dob scope. It really hard to find anything interesting beyond planets to find in the sky. I want to make discs that are marked for my latitude, marked by degrees so i can go to where something is in the sky without an hour of hunting.
18:46 would a propeller system like ingenuity be useful on a solar panel lander to prevent dust since it seems like ingenuity hasn't had issues with dust yet?
Hoth question was annoying. Gravity from rotational acceleration can totally work. In fact, it would be easier to build such a station than create a spaceship that can accelerate at constant 1 g. (haha, I jumped the gun and responded in similar way to Fraser)
Exactly, plus it's already been demonstrated with centrifuges and even the Gravitron carnival ride. It's like the guy doesn't understand that rotation is an acceleration. Has he never taken a corner in a car???
@@filonin2 The problem is that an object with three axes having inertial moments I1>I2>I3, rotating one will cause one of the others to flip end over head at some point. For a tidally locked space station, though, the problem would be reduced to an occasional wobble, like you see a spinning top do.
Hey Fraser have you thought about doing a tour of the solar system series of videos spending maybe 1 hour will up to date info about the planets and moons ? That’s something I would love to see my 7 year old daughter loves the Q and A vids you do although I’m not sure she understands everything but she shows a healthy interest
I am sure you will be intrigued by the mind-stretching novel by Robert Forward entitled "Dragon's Egg". It was published many years ago, but is still up-there in respect of credible science.
Question: Assume you wanted to extend the life of the Voyagers and had the propulsion systems and resources to do so within half a decade; ignoring that those resources would likely be better spent on a completely new project, what updates, upgrades and additions would you suggest be done to them to keep them relevant for the next 50 years?
Hoth, at 11:20ish, got me thinking (dangerous, I know). Couldn't we design an airlock for delivery to the station as it's being constructed that would allow the transfer of a little bit of the incoming vehicle to the station, slowly spinning it up with every delivery? It would be easier, I'd wager, than starting a larger part, say the first wheel, spinning from a stop - and use less energy, too. Incoming ships always have to slow down to a stop to match the ISS, or Skylab, before it. This would just save them a bit of booster energy and save us on spin-up energy. Sounds like a win-win to me!
My favourite book involves the first crewed lightsail from Earth to visit another star, The Flight of the Dragonfly by Robert L Forward. Have you read that one?
On your point of launching all the materials into orbit, to build a large spinning spacestation is that its parts and stuff could be made on the moon, not using any terrestrial materials at all. Or nearly none. Just thought I would throw this out here. Be kind, I just subscribed :)
Hoth. And no, the difference between 'Centrifugal force' and constant acceleration (9:03) will be discernible. With the rotating space station, you will feel the Coriolis effect which would create different sensations than anything that doesn't rotate.
There's a carnival ride that the asker of "Hoth" should try out. You and the other riders stand against the inside walls of a cylinder, and then it spins up and sticks you to the walls. The sensation is suddenly of lying on your back, and you can lift your feet off the ground. Not only would the "wheel in space" work, but you can already try it out.
Hey Frazier. Your in my top 3 channels on UA-cam. Question has there ever been a real moon rock or rock from another rocky planet in human hands on earth. If so how would it be verified?
Sure, there are all the rocks brought back from the Moon during the Apollo missions. There are also chunks of Mars (about 300 found so far) that fell to Earth after being blasted off the planet millions of years ago by a meteor impact. How do they know? Obviously, the Apollo astronauts hand delivered the Moon samples. For the Mars meteorites, they slice them up and measure the gas inside to see that it matches the atmosphere of Mars when the rocks first formed.
Just on that topic of telescopes on the moon. It's the low gravity (0.16g) that suddenly makes it a whole lot easier to engineer the support structures. The problem with Earth based telescopes is that as you build larger and larger support structures, the mass goes up almost exponentially. On the moon it would be vastly easier to build a (say) 100m optical telescope whose support structure would look flimsy, if on Earth.
"Stark" by Ben Elton is incredible! It's about a conspiracy of ultra-wealthy businessmen who have invested in a space program (the launch facility of which is built in secret on land owned by an indigenous community in desert Western Australia) in order to escape an Earth that's dying from climate change and pollution ... but I'll leave it at the basic premise. It was written in 1993, so it's having its 30th anniversary this year (I actually want to organise a screening event of the AMAZING mini series from the same year). It's probably one of the funniest books I've ever read - for anyone familiar with Ben Elton's work, that would seem obvious - and it totally changed my outlook on life and the world, and the world's place in the cosmos. To say that it's prophetic is an understatement. The only issue is trying to figure out with ultra-wealthy space "personality" of today corresponds to which character. I'm gonna say that Musk is definitely deQuincey and Bezos is Tyrone (maybe; if only he were Australian). Haha. To know why, you gotta read it. Can't recommend it enough to anyone. The mini-series, which stars Ben Elton (who also did the incredible screenplay) and Jaqueline Mackenzie (whose character I've had the biggest 'fiction crush' on since I first saw it) is definitely worth a watch. And it's not a case of "the book is better", etc., either; both are brilliant, and in either order. Pretty confident you'd LOVE it!
Aerodynamic Reynolds Number dictates that large aircraft are more fuel efficient than small ones, hence big jets. At low Reynolds Numbers, like for bees and birds different designs are required.
A large, rotating space station does have a constant acceleration. The amount depends on the size and rotation velocity of the station. Look up uniform circular motion.
The ion engines that NASA has used put out about the same force as the weight on Earth of a single sheet of paper. So take your own weight, divide by the weight of a single piece of paper, and that's similar to what you get. It's somewhere BELOW 1% of Earth gravity.
Hoth: Couldn't you on a regular basis switch the direction of gravity by switching between accelerating and decelerating (even to the point of switching directions)? I'd watch that movie XD. You wouldn't have to actually move continuously but could move back and forth "near" one spot, though you would also have to turn your spacecraft or you'd have to flip ceiling and floor whenever you switch the direction of simulated gravity. Or if near a source of gravity you could just hover in place over the source and match local gravity or constantly fire normal/anti-normal while in orbit and move your orbit of center but allowing for partial gravity.
Not fair! You win the best question’s answer every week! 😂😂 Maybe bring someone else to answer some of them every now and then? Cheers! Love your content!!
Q: Is it possible to view the recent wrecks on the moon's surface? I'm curious if any big telescopes were pointed at the Indian and Japanese crash sites.
Is gravity the same as constant acceleration? I am not a mathematician or a theoretical physicist but it seems to me that constant acceleration would only mimic gravity in the direction of the changing velocity? But gravity seems to affect objects in every direction?
If Im correct in my calculations acceleration at 1g would reach the speed of light within about 5.28 hours. Since the mass if the ship would increase as we approach the speed of light it would become increasingly more difficult to sustain a 1g acceleration. So for that reason alone it would be impossible to sustain 1g acceleration even on an interstellar flight. I don’t know the answer to something though. As the mass of the ship and its occupants increases would their gravitational attraction increase and provide some form of useful actual gravity
Bespin made me sad, because I'll never be able to afford something like that. 😭 Mustafar makes me sad because I want the ISS to become a museum, not scrap metal burning up in the atmosphere or crunching into the Pacific. 😭 Kamino I think was the top interesting Q&A, this time, with Hoth running a really close second. Not that you ever have boring questions and answers, Fraser! But you want us to choose, as impossible as that is to me, LOL!
Q: I'm fascinated by the possible habitability of Teegarden b and c. Aren't they both likely to be tidally locked? If so, wouldn't optimistic scenarios mean a habitable rim near the terminator of Teegarden b's daylit side? And doesn't Teegarden c stand a chance as an eyeball world, potentially temperate where best lit?
Naboo. How are the helical paths of the Voyager probes explained? It's like they inherited some kind of helical orbit if you look at their paths using the sun as fixed reference frame. Is one of the reasons Solar Sails are faster due to them avoiding inheriting unwanted directional momentum from bigger objects by not slingshotting around them?
@@nicholashylton6857 I should've asked it on the video where it showed a trajectory of the voyagers where they were obviously not in a straight line. I'm not sure how that thing was generated but it had a helical path (not an orbit, for clarity).
@@Yezpahr You were looking at the orbit relative to another body. They look helical if you are not centered on the Sun or you take into account the motion of the entire solar system. Play Kerbal Space program and change the views for the orbits.
Each path segment of the Voyagers was elliptical, until they reached escape velocity when they became hyperbolic. With each gravity assist, the foci of the ellipse would change, giving the illusion that the path is a helix. Solar sails would have to follow similar paths as they are sailing vessels, not parachutes. Photon pressure is not enough to keep a solar sail aloft above a fixed point, but can and does add a little momentum to a vessel already in orbit around the sun.
@@CyberiusT We need to think but I'm sure a lot: -standard modular inter-structure agregation; -protective technology not to be rotated; -independant management; sevices oportunity; many building operating outside the rotating structure to save floor space; I'm even not sure there gonna be enough room on that caging mesh than to build several layers of mesh.
@@biquettier Perhaps I'm just being thick, but I can't see why any of your points would require a fully-encasing mesh or cage. Many ships in SF movies include rotating and 'stationary' sections, for example.
@@CyberiusT How can you exchange a rotating module from a sci-fi ships, modularity is important. A very important advantage of a fully-encasing mesh or cage is applied either for exploration ships with rotating module or for huge long-lasting living purpose rotating structure: It acts as a stabilizator among all the rotating structure, enabling vertical propulsion movement or creating a redondancy system on huge structure. Made of electro-magnetical forces to stabilize the rotating structure. And I never saw a sci-fi ship with massive raw meteriel stockage system, since it would probably use the cage system.
Hey Fraser could helicopters’ downdraught finally solve the dust on solar panels problem? Should NASA fly Ingenuity low over Perseverance to test how much dust is blown off the rover?
@Mr Fraze could we use ai agorythoms to run a network of robots like the boston dogs to rome mars sampling and building ready for humans to land? and we just log on to the system daily for updates, to controle etc,
Artificial gravity hoops are cool, but what about weight distribution? A rotating ring with all the weight on one side will wobble after all! I'm guessing you might be able to pump water around to redistribute the weight, but what are the limits and how hard is it from an engineering perspective?
Time dilation question. How does a person age differently depending on where they are located in the universe as compared to a person age on earth? On earth we are traveling through space at 29.78 km/s which to us on earth is equal to 1 year for 1 year, but if a person was cloned & placed on other objects moving through space faster or slower i.e. Mercury is moving at 47.87 km/s, Pluto: 4.74 km/s or the star, named S4716, travels at around 8000 km/s age differ or for example what would each cloned person's "earth age" be if they were brought back to earth after 100 earth years? Thanks!
Sorry follow-up... If time moved slower for another intelligent species in the universe due to an increase in their speed in space, be able to have a comparable longer time to develop more quickly than us?
Does gravitational lensing work with radio like it does with optical and IR? I mean, in the same way, by the same amount. Has anyone pointed a radio telescope at Stephan's Quintet? If we're able to make the Solar gravitational Observatory technology work, would a second one operating in radio frequencies be a good idea or does radio not bend in the same way other frequencies do?
I still think that gradually boosting ISS into graveyard orbit is feasible. Yes, it would take many trips with Russian spacecraft but could likely take fewer trips with some US spacecraft. A variant of SpaceX Starship for example could provide many times move delta V than Soyuz/ Progress.
Question for the question show. Black Holes gravity are so strong that light can't escape and they actually bend the spacetime around them, and end at a singularity. Could it be possible that our universe could be inside a black hole, and each black hole is a different universe being we can't see into them and nothing can escape. Being our universe started at a singularity. What are your thoughts? Charles A.
![NASA’s First Step To A Cloud City on Venus [NIAC 2025]](http://i.ytimg.com/vi/IYD5DIVgDGo/mqdefault.jpg)
10:22 This is why Expanse is *the best* at hard sci-fi. When the ship is en route they spend half the time accelerating and half the time in decel flying "backwards" and therefore the ships are structured vertically like towers and not lengthwise like maritime vessels while for space stations they simply use spin gravity.
And additionally, this is why LDSS Nauvoo looks like a barrel. It is essentially designed to be a space station tumbling through interstellar space at no acceleration through most of it 100 year journey, therefore it is designed to be spun up as it stops accelerating.
Replying to first paragraph - you don't need to read a lot of scifi to get that. In revelation space series, it's just that way by assumption. Like the author doesn't need to explain it he's like yeah of course that's how it works.
Yeah the Nauvoo is a typical cylindrical ship design, those go all the way back to rendezvous with rama like decades and decades ago. Probably before that.
@@ericv738 Neither does the Expanse (at least it's not emphasized), and whaddayaknow sadly many people, even fans, miss this fact. The difference is that the other ones are books and none of them had a popular and carefully crafted and engaging TV show made after it meaning this kind of sci-fi was "locked" to only dedicated sci-fi fans and bookworms, while Expanse started to introduce the hard sci-fi concept, in a very fluid and engaging manner, to the broader audience, which is a very good thing.
My problem with constant acceleration under rocket power is that it is described as being in the jaws of a terrier.
Question: Is it a lot smoother once out of the atmosphere?
@@philipyoung7034 It's the atmosphere. Assuming you design your rocket engine/thrusters correctly.
Thanks for this great episode Fraser and patrons!
Really enjoyed the video Frasier, thanks. One thing I wish you had mentioned when discussing using tethers for an artificial gravity system is that due to the compact storage and light weight of a tether system compared to a rigid structure the ability for tethers to extend the diameter of the rotating mass well beyond what is possible with a rigid mechanical structure makes a lot of sense. The reason extending the diameter is desirable is what that does to reduce the problems inherent in using rotation to simulate gravity.
Rotation simulates gravity fairly well if the structure's diameter is several times the persons height and while the person is stationary within the structure, but when the subject moves strange things happen. There are several videos on this on youtube. Even throwing an object (a ball, etc.) in this situation causes the path of the ball to curve. The anomalies can bring on motion sickness and other issues. These effects are reduced by increasing the diameter of the rotating mass. Most hard structure rotating space stations proposed, even large ones, would suffer from these issues rather significantly. However when using tethers it's not out of the question to use diameters of more than a mile for example. This would make the environment much more tolerable and do a much better job of simulating earth-like gravity. One thing you have in space is, well, a lot of space. Why not take advantage of it?
Glad you finally read Accelerando, it's in my top 5 favorites along with Diamond Age, Quantum Thief, Diaspora, and Incandescence. It was written in 2005 and the predictions would have been more accurate if the Dotcom bubble didn't happen and the optimistic early days of the internet continued to develop.
Fraser should definitely read some Greg Egan. Diaspora or Permutation City.
@@tau3457 Permutation City definitely.
Naboo got me relieved because it means gravitational lens telescopes are more feasible than I previously thought!
You should do this show with hand puppets, DR. MARVIN!
I just want to say I'm so happy UA-cam recommended your channel to me because I love your channel and love your encouragement to ask questions and for being so courteous and professional even to the trolls. ✌️😎
Thanks a lot, welcome aboard.
Voyagers are at about 159 AU right now and it takes some impressive technology to even communicate bytes of information with them at that distance. We'd need communications improvements of several orders of magnitude to be able to download quality image data from a telescope at 500+ AU. I doubt we're anywhere near that right now. Perhaps we'd need some powerful relay probes every 100 AU to pull that off.
Relays seems like a good answer. We could grab a bit more data from the voyagers on the way past.
I wonder why we didn't launch a pair of voyagers every decade or so.... Could have used relays to extend mission life by multiples, I guess. Also data in depth.
I'd think we'd have some advancements in communication technology since the voyager equipment was launched
@@dougselby7592 The 500 AU "Sun_lens" Einstein_ring, single_target, disposable telescopes will not slowdown or enter an orbit (they will work until they get too far away from the lens_focus).
. Since observing exoplanets in detail requires time (seasonal changes in clouds, dust storms, ocean/forest coloration shifts, etc); multiple identical ones will be sent on regular series (maybe changing the cameras for fine tunning sensitivity to specific color/band absorpion); with the same shape, size & capabilities to constantly replace the previous one.
. An RTG can keep the electronics & batteries warm, but to supercool the sensors and send data at high bitrate (compressed, encripted & re-sent multiple times for error correction); even using its replacements as relay in daisu chains... it NEEDS a nuclear reactor.
-> Not much "fuel" is necesary (little extra mass for the fission reactor & anciliary batteries, no pumps if using passive dissipation and "pulsed" scheduled power production)
I think any improvements in tech we get will only let us detect their signals for longer, but maybe not improve the bitrate they're transmitting it at I wouldn't think
From the calculations I've see a constant acceleration of 32-feet per second per second for about a month your ship would approach c -- the speed of light.
I looked around a bit and couldn't find that answer, or any solid answer. Thanks.
Yes, but you actually keep on accelerating at 1G forever. You'll never actually reach the speed of light but you'll experience more and more time dilation. You could travel billions of light years in a single human lifetime.
I was trying to hold off, but I’ll be that guy… acktually…
From the perspective of a stationary observer, say anyone on Earth, a spacecraft continually accelerating at 1 G will get arbitrarily close to C. From Earth’s perspective the spacecraft will need a minimum of 4.24 years to get to Proxima Centauri.
Subjectively the spacecraft could go well beyond C thanks to Lorenz Transformation. Time dilates to make it seem Earthlings are running at 2x or 10x or some-arbitraryX. Distances along the line of acceleration shrink so it won’t feel like Proxima is all that far away on top of getting faster.
The downside is the time mismatch between the spacecraft and Earth. The spacecraft could get to Andromeda and back within the lifetime of the astronauts if they could get to 99.99% C. But Earth will be at least 10 million years older than when they left. If humanity hasn’t died out they will have long since forgotten about the astronauts. More likely the astronauts are coming home to a planet ruled by intelligent cockroaches or intelligent octopuses.
@@cancermcaids7688 The acceleration of Earth's gravity is 32-feet per second *squared.* First second is 32', next second 64', next second is 128', etc.
And also… after getting to 80%+ C any small atoms (even in rarified space) you hit are going to hit like hard gamma rays. Gonna need those Larry Niven magnetic monopoles to protect it.
Coruscant ! Love the “engineering of concepts” type questions ( and answers) more please 🙌🏼
My question: How to decelerate from (near)lightspeed, if we ever be able to travel at lightspeed. The target can be overshoot very easily. And how to avoid collisions with whatever comes into collision with a lightspeed traveling object? You need lightspeed correction capability.
BIg fan of your show! Thank you for sharing your content. Best regards from the Netherlands.
NABOO !!! I had wondered this a bunch of times and your answer was the happiest possible outcome :)
Speaking about telescopes I would enjoy knowing someone with a telescope that was happy to show me the night sky. The one evening I had the opportunity years ago viewing Saturn was brilliant. Something about seeing with your own eyes 🤘🇦🇺🌌
Love this part of the week. 1:05
I like the artificial gravity method from “Project Hail Mary” and “Seven Eves” with the tethers. It seems reasonably buildable.
Hoth.
1g doesn't seem too much in the short term. But, can you imagine the energy requirements in any real length of time? I thought you did a segment on this a while back where 1g approaches the speed of light... eventually. One G acceleration is a great sci fi topic. I like it.
iirc at 1g you'll reach c in about a year
@@washinours No, you will never reach c at any acceleration, ever. You would simply get closer and closer to c without ever getting there.
@@filonin2 Then the acceleration would be reduced also the closer you approach (but don’t reach) the speed of light, due to more and more energy needed to keep accelerating the mass? Maybe I got this wrong, but this is how I understood the physics involved? Have a great day! Br
@@mhult5873 theoretically if there were no other matter in the universe and a had a hyper efficient rocket, you could keep experiencing that 1g acceleration indefinitely. Every time you dropped a marker off the side it would fall away at 1g. Practically, you would eventually run out of fuel, or length contraction would make the imperfect vacuum of space so dense that it would take more and more force to push through so you never reach c relative to the universal center of mass. At any rate, if you were to you reach the escape velocity of the local galaxies, metric expansion would eventually push you past c relative to the starting point
- If the X Y, and Z axis changes in space..? What do you use as reference point?
- Gyros in space and its benefits to Human space transport.
- The difference in takeoff/landing between Earth and Mars? Even the Moon? I know there is a substantial +/- pull, push = apogee towards thrust, but how can that benefit humans?
- What are some of experiments that have been completed on the ISS that have already helped humanity, along with Space Flight?
Sorry for the question, just super curious. I have a ton more.
Thanks for a great episode.
- NOM
Accelerando is a great book. One of my favorites.
Yavin The scceleration of the number and magnitude of exploratory missions is mind boggling.
Hoth! Because there are so many questions for engineers and medical science to answer about artificial gravity.
Tatooine and thank you for your patience!
Naboo. That's pretty cool that it is a focal cone instead of a focal point
I think one snarky sarcastic question per question show is a great guidline.
Hah, I think that's the right blend.
Ha...30.34...is space exploration the domain of introverts? As a psychologist and an introvert I know we love working alone/in small groups...I know I would I be happy with a few years of limited interactions with others :)
I used to say no way, but since my life changed so drastically that I have no one that I would miss other than those I can just text and call like I do now, sure, I'd be fine with it. Only thing is, now I'm too old, and I'm disabled, so I'm out of luck. 😂
When I was young and in shape, I'd never be able to do it mentally & emotionally. Now that part won't affect me, but I'd never be able due to fitness and age. 🤷🏽♀️ Now that, as a really old satirical song said, means "if it weren't for bad luck, I'd have no luck at all!" 😂
Great show. Thanks for doing it.
Sorry, not sure how to ask a question to get it addressed during live podcasts...but, 5.50 shape/size of moon craters....my first question is, when was the most recent 'significant' asteroid collision on the moon that we can detect through modern observations, and second question, do we monitor for potential 'significant' asteroid collision with the moon, for the potential catastrophe being that the moon/its orbit/or debris has the potential to impact the earth?
I believe there was an lunar asteroid collision caught on video on February 23, 2023. Not sure if it qualifies as significant to you.
@@00dfm00 cool...I didn't hear about that...will look it up
Question for next show: are there any stars exactly located at the barrier of the observable universe, that we could watch leave the observable universe?
if no, is it possible, and what would it look like?
Oh, book recommendations!
A favourite of mine is 'Chasing Venus: The Race to Measure the Heavens', by Andrea Wulf
It's about the transit of Venus, but it's also about some of the explorers who were attempting to record the transit, and... it's great. Some of the journeys were absolutely mad.
I can't recommend it enough. I've lent my copy out several times and I'm always a bit relieved when it eventually comes home 😁
9:20 Assuming you are standing up, if you could measure the difference in gravity between your head and feet then you would know if you were in an elevator where everything is the same or else you're in one of these: on a planet etc or in a centrifuge. I don't know if greater sensitivity would answer which one.
Bespin
Just upgraded my AP rig yesterday. I’m all in for building your own rig, but these serve a purpose to make electronically assisted astronomy accessible.
Yup, if youve got the skills and patience, build your own rig. If you just want go outside and see some cool stuff, these automated scopes are the way to go. Especially if you're rich.
@@frasercain god bless cloudy nights classified adds!
Alderaan.
Have to see Stowaway. Robert Zubrin has mentioned having a tether between the spacecraft and the upper stage as a strategy to combat the effects of weightlessness on the way to Mars.
I hope you've read Voyage of the Space Beagle Fraser, because you are the best Nexialist I know of.
The snarky troll questions are useless. People that dont think science is real are not going to suddenly start. So i vote for NOT the troll questions.
I will admit the snarkiness was not very nice. But the question was earnest,...how do "they", whoever they is, determine so much information from a light dot on a slide? It's a legitimate question that believers of science dogma refuse to stop and ask. The scientific method requires empirical evidence that can be physically demonstrated. Hypothesizing what light dots are on a space telescope slide is NOT demonstrable evidence; therefore no scientific method has been used to determine the answer to the question.
@@stephaniemcguire I respectfully disagree. The first step of the Scientific Method is formulating a hypothesis (or a guess, as it were). The ones saying the dot breaks the big bang theory are in fact the ones not participating in the scientific process.
@@nandesu I've made no references to big bang at all. I'm referring to a description of a light dot hypothesized to be a planet with certain presumptions made about it as if they were real.
I agree. Better off to just skip those questions/comments.
The goal when answering those types of questions aren’t to change their minds. It’s to explain what’s happening to those listening in who are unsure/undecided. It’s to educate those on the fence that genuinely wonder how things like this work, and to educate those who do trust the science but might not know how a specific things works.
Fraser, I have a question about gravitational waves. If they distort both space and time, then why do we not use an array of atomic clocks to look for the time distortion as the waves pass?
Instead, we use lasers to look for spacial distortion.
Is it even possible?
question: for artificial gravity, is there any advantage to a big wheel instead of having two capsules linked by a tether? the latter sounds easier to pull off and easier to scale up.
i imagine for a Mars mission you could have two starships connected nose to nose by a tether, one for the crew and one with supplies needed on Mars
Hey Fraser, this is a two-part question regarding the ISS. What would you say are the top three discoveries made from the ISS? At this point, what was the last main discovery made from the ISS, basically, in your opinion, is it still worth us? Keep it around when that money can be allocated somewhere else? Thanks, Jason
The problem with linear acceleration can be summarized simply as this. Accelerating at 1g for one year without lorenze correction is c.
The rocket equation is dV = Ve * ln (Mi / Mf) where Ve = exhaust velocity, Mi = initial mass, Mf = final mass of fuel. if t = dV / 9.8 and Ve = ISP * 9.8 then t (@9.8) = ISP ln (Mi/Mf). Mi/Mf is typically 3 to 4 and so natural log (2.68) of this is roughly 1. But because the mass decreases acceleration increases to 3 or 4 g. If we take the simple average it comes out to be about 3 * ISP. 😅
ISPs range from about 200 for hyperglolics and 460 for SSME H2/O2. So for traditional fuels runtimes at one g are between 400 to 1500 seconds (25 minutes)
For nuclear thermal rockets you could double or triple that.
For Ion drives there is no limit to ISP (OK, limit is C/9.8), and this is good because it spares fuel mass, but theres a problem. And its going to go back to the initial summarization
Suppose we wanted to accelerate for 1 year. So we want Ve in roughly the 1 x 10E8 meters per second.
So lets say we want an ion drive to do this. Our ship weighs 10 tons. We need 9.8 m/s newtons. So 9.8 x 10,000 kg = 98,000 Newtons
The ion drive equation is
Force = Power x Efficeincy / Ve
So 98000 = Power x 0.85 / 1E8
its something like 10 x 10E12 watts of power. Thats about the power needed to run an entire state. But thats only one problem
1. 15% inefficiency requires a huge mass for dissipating waste heat
2. There is nothing that can generate this level of electric power in space. Currently the ISS requires 14 kg per square meter of panel which deliver about 200 watts per meter.
So the answer to the question is more like this, you can generate milli-g of constant force in space constantly (conserving mass with high ISP) but it would be very difficult to get into the integer range of acceleration.
But if we think about the problem like this. If we could sustain a constant 1 g acceleration you could accelerate halfway to mars in a few hours, reverse acceleration and land in the same day. We would not need artificial gravity.
The problem in space is this, where is the energy? If you dont have a great source of energy, you not going to be able to do alot of things.
Coruscant - Moon telescopes! Yes! all of them, please. :)
For Hoth: We need Medina Station.
Many thanks for another great video! 🙂
That was what i quickly found out after i made a 15" dob scope. It really hard to find anything interesting beyond planets to find in the sky. I want to make discs that are marked for my latitude, marked by degrees so i can go to where something is in the sky without an hour of hunting.
18:46 would a propeller system like ingenuity be useful on a solar panel lander to prevent dust since it seems like ingenuity hasn't had issues with dust yet?
One good book read...The Mote in God's Eye. Interesting read on first contact and self repairing technology.
Hoth question was annoying. Gravity from rotational acceleration can totally work. In fact, it would be easier to build such a station than create a spaceship that can accelerate at constant 1 g. (haha, I jumped the gun and responded in similar way to Fraser)
Exactly, plus it's already been demonstrated with centrifuges and even the Gravitron carnival ride. It's like the guy doesn't understand that rotation is an acceleration. Has he never taken a corner in a car???
@@filonin2 The problem is that an object with three axes having inertial moments I1>I2>I3, rotating one will cause one of the others to flip end over head at some point. For a tidally locked space station, though, the problem would be reduced to an occasional wobble, like you see a spinning top do.
Pretty sure they made it back to the Alpha Quadrant, can’t wait for that infodump on fluidic space.
Good point, I want to learn more about Species 8472.
Hey Fraser have you thought about doing a tour of the solar system series of videos spending maybe 1 hour will up to date info about the planets and moons ? That’s something I would love to see my 7 year old daughter loves the Q and A vids you do although I’m not sure she understands everything but she shows a healthy interest
I am sure you will be intrigued by the mind-stretching novel by Robert Forward entitled "Dragon's Egg". It was published many years ago, but is still up-there in respect of credible science.
13:47 solar lens doesn’t have focal point but focal line
Question:
Assume you wanted to extend the life of the Voyagers and had the propulsion systems and resources to do so within half a decade; ignoring that those resources would likely be better spent on a completely new project, what updates, upgrades and additions would you suggest be done to them to keep them relevant for the next 50 years?
Capture them and put them in an exhibit, if you can catch up to them send a new craft to take their place.
Q: Could JWST see the voyagers? Just curious but, it would make an interesting observation.
Nope, It couldn't see them if they were orbiting the Moon.
Hoth, at 11:20ish, got me thinking (dangerous, I know). Couldn't we design an airlock for delivery to the station as it's being constructed that would allow the transfer of a little bit of the incoming vehicle to the station, slowly spinning it up with every delivery? It would be easier, I'd wager, than starting a larger part, say the first wheel, spinning from a stop - and use less energy, too.
Incoming ships always have to slow down to a stop to match the ISS, or Skylab, before it. This would just save them a bit of booster energy and save us on spin-up energy. Sounds like a win-win to me!
Alderaan - Great show!
My favourite book involves the first crewed lightsail from Earth to visit another star, The Flight of the Dragonfly by Robert L Forward. Have you read that one?
Have you read Aurora by kim stanley robinson?
Great show! I vote Hoth!
On your point of launching all the materials into orbit, to build a large spinning spacestation is that its parts and stuff could be made
on the moon, not using any terrestrial materials at all. Or nearly none. Just thought I would throw this out here. Be kind, I just subscribed :)
Controlled disposal into Point Nader, equal distances from Easter Island, Pitcairn Island, and Antarctica.
Hoth. And no, the difference between 'Centrifugal force' and constant acceleration (9:03) will be discernible. With the rotating space station, you will feel the Coriolis effect which would create different sensations than anything that doesn't rotate.
I think I said with a big enough space station, so you don't feel the Coriolis force
There's a carnival ride that the asker of "Hoth" should try out. You and the other riders stand against the inside walls of a cylinder, and then it spins up and sticks you to the walls. The sensation is suddenly of lying on your back, and you can lift your feet off the ground. Not only would the "wheel in space" work, but you can already try it out.
Yeah, the Gravitron. I used to ride it over and over. I really like the feeling.
Hey Frazier. Your in my top 3 channels on UA-cam. Question has there ever been a real moon rock or rock from another rocky planet in human hands on earth. If so how would it be verified?
Sure, there are all the rocks brought back from the Moon during the Apollo missions. There are also chunks of Mars (about 300 found so far) that fell to Earth after being blasted off the planet millions of years ago by a meteor impact.
How do they know? Obviously, the Apollo astronauts hand delivered the Moon samples. For the Mars meteorites, they slice them up and measure the gas inside to see that it matches the atmosphere of Mars when the rocks first formed.
Just on that topic of telescopes on the moon. It's the low gravity (0.16g) that suddenly makes it a whole lot easier to engineer the support structures. The problem with Earth based telescopes is that as you build larger and larger support structures, the mass goes up almost exponentially. On the moon it would be vastly easier to build a (say) 100m optical telescope whose support structure would look flimsy, if on Earth.
Hey Fraser
do you see any chance of the space station being gobbled up by a few starships and being brought down to a museum or something like that?
"Stark" by Ben Elton is incredible! It's about a conspiracy of ultra-wealthy businessmen who have invested in a space program (the launch facility of which is built in secret on land owned by an indigenous community in desert Western Australia) in order to escape an Earth that's dying from climate change and pollution ... but I'll leave it at the basic premise. It was written in 1993, so it's having its 30th anniversary this year (I actually want to organise a screening event of the AMAZING mini series from the same year). It's probably one of the funniest books I've ever read - for anyone familiar with Ben Elton's work, that would seem obvious - and it totally changed my outlook on life and the world, and the world's place in the cosmos. To say that it's prophetic is an understatement. The only issue is trying to figure out with ultra-wealthy space "personality" of today corresponds to which character. I'm gonna say that Musk is definitely deQuincey and Bezos is Tyrone (maybe; if only he were Australian). Haha. To know why, you gotta read it. Can't recommend it enough to anyone. The mini-series, which stars Ben Elton (who also did the incredible screenplay) and Jaqueline Mackenzie (whose character I've had the biggest 'fiction crush' on since I first saw it) is definitely worth a watch. And it's not a case of "the book is better", etc., either; both are brilliant, and in either order. Pretty confident you'd LOVE it!
Aerodynamic Reynolds Number dictates that large aircraft are more fuel efficient than small ones, hence big jets.
At low Reynolds Numbers, like for bees and birds different designs are required.
A large, rotating space station does have a constant acceleration. The amount depends on the size and rotation velocity of the station.
Look up uniform circular motion.
That's what I'm saying, if you make a rotating station large enough, you won't feel the Coriolis force and it would be indistinguishable from gravity.
How much gravity could you get from a means of acceleration that'll last longer term?
The ion engines that NASA has used put out about the same force as the weight on Earth of a single sheet of paper. So take your own weight, divide by the weight of a single piece of paper, and that's similar to what you get. It's somewhere BELOW 1% of Earth gravity.
Hoth: Couldn't you on a regular basis switch the direction of gravity by switching between accelerating and decelerating (even to the point of switching directions)? I'd watch that movie XD. You wouldn't have to actually move continuously but could move back and forth "near" one spot, though you would also have to turn your spacecraft or you'd have to flip ceiling and floor whenever you switch the direction of simulated gravity. Or if near a source of gravity you could just hover in place over the source and match local gravity or constantly fire normal/anti-normal while in orbit and move your orbit of center but allowing for partial gravity.
the first book of cixin liu's trisolaris trilogz is interesting, no need to finish the three IMO
I think the first one is the weakest. The next two are way better.
@@frasercain i just liked the description of known technology framed by the historical context, and found the human characters' behaviors implausible.
Not fair! You win the best question’s answer every week! 😂😂 Maybe bring someone else to answer some of them every now and then? Cheers! Love your content!!
He does so on a regular basis.
Pandering will get you no where.
@@WillYouVid that’s cool, i didn’t know that.
@@Threedog1963 sharing your own experience? Thanks!
Question, Why does the Mars sample mission not keep all the samples together and leave them in one spot ?
Q: Is it possible to view the recent wrecks on the moon's surface? I'm curious if any big telescopes were pointed at the Indian and Japanese crash sites.
Earth based telescopes cannot resolve any man made objects on the moon.
Is gravity the same as constant acceleration? I am not a mathematician or a theoretical physicist but it seems to me that constant acceleration would only mimic gravity in the direction of the changing velocity? But gravity seems to affect objects in every direction?
For the Mustafar question, the name of the place is Point Nemo
perfect time
Dagobah. Also a moon crater is rarely pointing where we want it.
If Im correct in my calculations acceleration at 1g would reach the speed of light within about 5.28 hours. Since the mass if the ship would increase as we approach the speed of light it would become increasingly more difficult to sustain a 1g acceleration. So for that reason alone it would be impossible to sustain 1g acceleration even on an interstellar flight.
I don’t know the answer to something though. As the mass of the ship and its occupants increases would their gravitational attraction increase and provide some form of useful actual gravity
Bespin
I could have never imagined this technology when I was a kid
Bespin made me sad, because I'll never be able to afford something like that. 😭 Mustafar makes me sad because I want the ISS to become a museum, not scrap metal burning up in the atmosphere or crunching into the Pacific. 😭
Kamino I think was the top interesting Q&A, this time, with Hoth running a really close second. Not that you ever have boring questions and answers, Fraser! But you want us to choose, as impossible as that is to me, LOL!
Q: I'm fascinated by the possible habitability of Teegarden b and c. Aren't they both likely to be tidally locked? If so, wouldn't optimistic scenarios mean a habitable rim near the terminator of Teegarden b's daylit side? And doesn't Teegarden c stand a chance as an eyeball world, potentially temperate where best lit?
High energy object collisions cause Kinetically induced, rapid disassembly in wave form.
Alderaan - didn't Scott Manley consult on the "two craft with a tether" idea for that movie?
Can they turn the solar panels vertical while flying?
I wonder how large a ball of iron you would need for it to collapse into a black hole?
Naboo.
How are the helical paths of the Voyager probes explained? It's like they inherited some kind of helical orbit if you look at their paths using the sun as fixed reference frame.
Is one of the reasons Solar Sails are faster due to them avoiding inheriting unwanted directional momentum from bigger objects by not slingshotting around them?
"Helical orbit"? The Voyagers have achieved escape velocity from the solar system. They're not orbiting the Sun.
@@nicholashylton6857 I should've asked it on the video where it showed a trajectory of the voyagers where they were obviously not in a straight line. I'm not sure how that thing was generated but it had a helical path (not an orbit, for clarity).
@@Yezpahr You were looking at the orbit relative to another body. They look helical if you are not centered on the Sun or you take into account the motion of the entire solar system. Play Kerbal Space program and change the views for the orbits.
Each path segment of the Voyagers was elliptical, until they reached escape velocity when they became hyperbolic. With each gravity assist, the foci of the ellipse would change, giving the illusion that the path is a helix.
Solar sails would have to follow similar paths as they are sailing vessels, not parachutes. Photon pressure is not enough to keep a solar sail aloft above a fixed point, but can and does add a little momentum to a vessel already in orbit around the sun.
Why we never see rotating station inside a bigger structure, like a bicycle or caging mesh?
Why would you need one? Unless you have some really good reason for it, such a structure is just a very expensive waste of material.
@@CyberiusT We need to think but I'm sure a lot: -standard modular inter-structure agregation; -protective technology not to be rotated; -independant management; sevices oportunity; many building operating outside the rotating structure to save floor space;
I'm even not sure there gonna be enough room on that caging mesh than to build several layers of mesh.
@@biquettier Perhaps I'm just being thick, but I can't see why any of your points would require a fully-encasing mesh or cage. Many ships in SF movies include rotating and 'stationary' sections, for example.
@@CyberiusT How can you exchange a rotating module from a sci-fi ships, modularity is important. A very important advantage of a fully-encasing mesh or cage is applied either for exploration ships with rotating module or for huge long-lasting living purpose rotating structure:
It acts as a stabilizator among all the rotating structure, enabling vertical propulsion movement or creating a redondancy system on huge structure. Made of electro-magnetical forces to stabilize the rotating structure.
And I never saw a sci-fi ship with massive raw meteriel stockage system, since it would probably use the cage system.
tatooine!
Thanks Fraser!
Hey Fraser could helicopters’ downdraught finally solve the dust on solar panels problem? Should NASA fly Ingenuity low over Perseverance to test how much dust is blown off the rover?
That would be too risky. If something went wrong they could risk damaging both vehicles.
@Mr Fraze could we use ai agorythoms to run a network of robots like the boston dogs to rome mars sampling and building ready for humans to land? and we just log on to the system daily for updates, to controle etc,
Artificial gravity hoops are cool, but what about weight distribution? A rotating ring with all the weight on one side will wobble after all!
I'm guessing you might be able to pump water around to redistribute the weight, but what are the limits and how hard is it from an engineering perspective?
Q: why did SpaceX use an untested Launchpad for their newest rocket? Do you think SpaceX regrets launching so early?
Time dilation question.
How does a person age differently depending on where they are located in the universe as compared to a person age on earth?
On earth we are traveling through space at 29.78 km/s which to us on earth is equal to 1 year for 1 year, but if a person was cloned & placed on other objects moving through space faster or slower i.e. Mercury is moving at 47.87 km/s, Pluto: 4.74 km/s or the star, named S4716, travels at around 8000 km/s age differ or for example what would each cloned person's "earth age" be if they were brought back to earth after 100 earth years?
Thanks!
Sorry follow-up...
If time moved slower for another intelligent species in the universe due to an increase in their speed in space, be able to have a comparable longer time to develop more quickly than us?
Does gravitational lensing work with radio like it does with optical and IR? I mean, in the same way, by the same amount. Has anyone pointed a radio telescope at Stephan's Quintet? If we're able to make the Solar gravitational Observatory technology work, would a second one operating in radio frequencies be a good idea or does radio not bend in the same way other frequencies do?
if you travel constantly with a 1g acceleration, it takes about a year to reach the speed of light and you would take half of a lightyear distance
Fun fact, at constant 1g thrust you would be reaching light speed in like a year or so... 1g of thrust is massive...
Is there any possibility to whip something out into space or in space?
I still think that gradually boosting ISS into graveyard orbit is feasible. Yes, it would take many trips with Russian spacecraft but could likely take fewer trips with some US spacecraft. A variant of SpaceX Starship for example could provide many times move delta V than Soyuz/ Progress.
Agreed. Parking the ISS in a "graveyard orbit" would let us re-activate it, if needed.
Question: why don't they send the ISS to the trailing Legrand point? or other points?
If you accelerate at 1g, you will reach the speed of light in nearly exactly 1 year. Would be nice to do that & see what happens.
They are coming.
It's made a mess everywhere.
What is the relative size between crewed Starship and one/various Sci-fi ships?
Question for the question show.
Black Holes gravity are so strong that light can't escape and they actually bend the spacetime around them, and end at a singularity. Could it be possible that our universe could be inside a black hole, and each black hole is a different universe being we can't see into them and nothing can escape. Being our universe started at a singularity. What are your thoughts?
Charles A.
It'd be awful hard to get that much mass into a black hole, so no.
Cool