Cool worlds, Isaac Arthur and Event Horizon for sharpening the knowledge knife. JMG and history of the universe/earth for falling asleep while boosting those free neurons during ones sleepcycle
Even though I know antimatter is a long way off that to me is one of the most fascinating ideas for space travel and I just really want that to be a thing now!
Containment is the biggest problem when designing the drive from the anti-matter (after obtaining the required amount of it). Actual drive would be relatively straightforward among the futuristic drives, proton/anti-proton reaction produces short-lived charged Pions that can be directed via magnetic field in one direction and extract big part of the energy directly as thrust.
It's highly likely that certain fringe scientists within some skunkworks-operation already cracked the code of superconductive(yes, at room temperature) cyclonic anti-gravity engines. I have seen quite a few UAP in LEO lately while staring through my telescope. I've seen nothing weird in the 25 years before that. Ofcourse one cannot openly admit that, but I have no problem with admiting the observation to you here. The stigma is kind of going away to, at least, casually mention it. That or it's aliens, but that would require braking a few laws of physics probably, because if said aliens were somewhere in our cosmic backyard then we would have spotted their presence.
Antimatter technology is primarily battery technology. We could create as much as we want if our societies accelerated the development of fusion technology or solar collection satellite tech. Then we might be able to develop the tech required to efficiently convert energy into antimatter and store it efficiently within a few decades.
ITAR achieved a net positive energy production using their test reactor recently. Given our history, practical fusion should be achievable within 100 years at the very most.
Nice tier list you have there sir, Laser sail won out as I thought it might! Huge congratulations on the time on Webb by the way, I look forward to the results!
What about multi-stage interstellar systems? Are they viable at all? This video by Fraser Cain touches on them: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-E74Kg8NpCyE.html
I wonder if sub-luminal variants of the Alcubierre/warp drives could go up a ranking. Still requires engineering far beyond our current capabilities, but they are apparently possible to build within the bounds of well understood physics we know today, I.e. they require no exotic materials and dont violate causality.
You forgot a couple of serious possibilities even if we accept a minimum acceptable velocity of .1 C. A British company is developing a fusion drive that might have this potential and it is not a pulsed detonation drive, but if we oversimplify it is rather like an ion drive on steroids. It is possible that this drive or a more advanced, developed version of it would meet the 10% threshold. Also there is the nuclear salt-water drive which seems a little crazy but might actually work. Personally I would not have included chemical rockets at all given the amount of travel time. At a certain point a thing is simply not worth doing, and a 70,000 year trip to reach the nearest star is unworkable on so many levels as to be pointless.
Yes, I agree; the pulsed detonation drive from the 1960's Orion Project seems to occlude the vision of directly generation fusion energy in a continuous drive and using the particles and energy to create an effectively "ion drive on steroids". I tend to agree on the omission of chemical rockets due to the dictates of the rocket engine and the low top speed of exiting particle streams out of any chemical rocket. Nevertheless a sufficiently large chemical rocket with a small payload could exit the solar system and travel during thousands of years. Within a few million years much of the nearby spiral arms of our Galaxy could be visited. It can only make sense over thousands of years of human existence imo.
But here’s the thing: chemical is good for cheap. So if we develop something we have to use as a slingshot; it’s a great way to get a massive payload out to orbit; if for example we wanted to do a dual system where primary propulsion gets it as fast as we can and then we use something at the edge of the solar system as like a “railgun propulsion” like having a massive fusion generator way out at the end of the solar system where we smash antimatter as a final kick to move something from a medium speed into far deeper into the subliminal range.
Interstellar travel is one of the most fascinating things there is. Fortunately I think there is a lot more people getting interested in this kind of thing and also a lot of wealthy people are getting more interested in it so maybe it'll move a lot faster than it has at at least over the next 20 to 30 years maybe.
A huge advantage of laser sails and beamed power is that your "engine" stays comfortably in your home system. If one laser station breaks the ship may not even notice while a replacement is built. It opens up the option of building more stations after the ship has launched to keep pushing the acceleration and make up for losses as distance to the ship increases. Compared to carrying ludicrous masses of fuel and being dependent on your own engine it seems almost a no brainer. But you have to trust the home system will keep the laser arrays on line all that time, you need them for braking as well! You also have to trust nobody starts to wonder what else you could do with an extremely powerful laser array in the solar system. Or in the case of nuclear pulse how you plan to sell the idea of manufacturing potentially hundreds of thousands of gigaton range bombs without raising any eyebrows. Basically any remotely interesting interstellar drive is also a weapon, more than rockets already are. This does lean into the "wait calculation" which might be a good follow up. We might have the tech to launch something at a few % of c, but that might be overtaken by something launched later using better propulsion. And so on. There's a very tired scifi trope where a generation or sleeper ship reaches its destination and finds it's already been colonised by FTL ships millenia earlier. You might argue against any interstellar mission until we have beamed power or antimatter production online, otherwise we're wasting resources on slow ships that will get overtaken later.
I feel like the most difficult part of interstellar travel won't even be the propulsion... It will be dealing with any interstellar dust clouds you might encounter. If your star ship is going 10% of the speed of light and hits something the size of a grain of sand then the amount of energy is equivalent to a small nuclear blast. You wouldn't be able to go above low speeds until you got past the kuiper belt for fear of blowing up your ship, and even then if there is some sort of interstellar dust cloud you'd have to be able to slow down while passing through it or shield yourself from extreme amounts of energy on the frontward facing portion of the vessel.
Maybe send 200 million disposable ships and hope one gets to the destination. If that sounds flippant, consider that it is the solution used by biology to successfully fertilize the egg that each of us owes our existence to.
Several solutions -- from Fraser Cain's interviews (qv) and Isaac Arthur(qv) -- have been proposed. E.g. lasers -- blue shifted by the spacecraft's 10%c -- would vaporize interstellar sand-sized particles.
Good point. I would suggest sending out unmanned probes at arbitrarily high velocities to see what happens to them (e.g. how often and how severely are they affected by impacts with interstellar dust?).
2 ships are moving through space, with 50% the speed of light. The first ship would have a huge steel dome (100m in diameter or larger) clearing the path for the other one, the other one which carry the important stuff would travel about 1 AU behind it with the same speed (16 minutes behind it).
I've seen some papers that suggest Alcubierre style drives that are subliminal (thus no causality violations) , and don't use exotic mater but specially placed mater which I'm still trying to get info on. Might be our best approach ?
The subliminal variant still depends on locally generating a sustainable and stable warp field so it still requires engineering a technology that has been barely demonstrated in the lab to exist, Nevertheless; pursuing the technology, whether negative energy and exotic particles can be created is our best bet for achieving superluminal travel which is key to reducing relativistic time difference between arrival and destination points.
@@micha9000 you can't pursue something that doesn't exist. No such thing as negative energy, mass or exotic particles. Not everything in the universe has opposites
My favourites are Plasma Magnet Sails with dynamic soaring and Zebrin's Dipole drive. My favourite FTL concept is Musha Jump Drive, will will have the exawatt chirped laser pulses for breaking spacetime any year now..
We're gonna build a Dyson Swarm to build Automated Interpolation models, so stick lasers on it and send manned spacecraft up to over half c with 1G acceleration maintained for a year.
Would be good for a robotic survey craft... but a 'manned' craft would probably want to slow down at some point... or it would basically be a relativistic joy-ride that never ends (except with a collision).
Here is my idea: use superheated mercury to repel a magnetic field then have it cycle back to liquid form and so forth. Mercury drive. I got this idea from ancient texts 👀
This might be a poor idea based on a perpetual motion device; i.e. a a stream that runs a waterwheel that deposits the flowing water to a stream uphill that flows down to the original stream path that runs the same waterwheel.
I believe when talking about space travelling, we ought to separate earth-to-orbit from all space travel per se. Imagine like you have a big tanker in a complicated port town, where you need the tanker to be pulled in an out by an smaller ship, while in the wide ocean, it goes by itself. I doubt we will come up with anything (other some megastructures) that will make chem rockets obsolete on the earth-to-orbit stretch... but, the pulse propulsion could really shine if built IN ORBIT. Maybe in moon's orbit, and depart from there... not problems with the nuclear booms that way, right? Final Thought: In the end, I think a sum-up of various of those ideas are what will probably do the trick... Why should they be mutually exclusive? Go to orbit with chem: build actual interstellar ship in space. Ion Drivers for cruising along the way Solar sails on the first stretch, probably the power up with nuclear stuff. Laser pushing after Neptune or the Jovian system? Blow booms to deaccelerate (since you won't have the laser rig at the destination). Whatever else works for course correction and get extra speed (gravity assists, nuclear thermal, etc) Extra: you need a power source for the craft anyway, and a good one to also power the I.D.... whatever leftover heat from a nuclear generator (I don't see a better option for a century long trip) can be used as nuclear thermal propulsion.
Good ideas. The solutions I see seem to work best when various technologies are combined together. Also I think the international rules are backwards; more restrictions should be placed on nuclear devices on Earth or inhabited colonies and less restrictions for space. Your last point depends on the thermodynamics.
Antimatter is likely the most realistic way for us to reach relativistic speeds with spacecraft so I'd put it higher up. It's almost certainly not something we can do in the next hundred, or maybe even thousand years-but as a consideration for future humanity, it's firmly within the laws of physics. I'd hope we would produce it off-world though, as accidents in use of antimatter might turn out to be a/the great filter to technologically advanced or interstellar civilizations...
I understand a condition of this tier list was whether or not it could be achieved within our lifetimes, but it's way more than one tier higher than a warp drive, or wormholes... and since chemical rockets launched today would take *way* longer to reach interstellar distances than a relativistic craft launched in 10,000 years, I'd say it wouldn't be one tier below those...
For me, the laser idea behind Project Starshot is the best one. It decouples the launch mass from the launch system and I think for any appreciable speed you need that property. This is actually what your Halo Drive does in practice. It builds probably the biggest and maddest version of the idea - using a blackhole to build a laser array of biblical proportions. My opinion is that your Halo drive will work and be practical sooner than you think, I suspect there are many small blackholes we simply can't detect. A lot of the missing mass of the universe could be these objects. There might even be such an object in our solar system, as some people think the Planet X object could be a low mass blackhole - with a size of a grapefruit. It would probably have tremendous rotational energy, being compacted to that size. For me, it would make sense to fund a mission looking for this object directly and seeing if we can locate it. If it was a a genuine blackhole, it would form a tremendous staging post for getting us out of Sol. It's far enough away that it's hard to imagine an accident capable of sterilizing the earth but close enough that it could be feasibly reached by another one of the nuclear drives in a short amount of time.
Been Watching you for years now. My daughter has grown up watching your videos and you have in part influenced her intense love for the stars. Thank you for what you do.
I guess it’s worthwhile to mount a robotic expedition to, say, Alpha Centauri, and just chill, as a species, until we can get.results generations in the future, but I think we could develop a warp drive in the meantime time and beat our robotic probe thereby a couple of years. It’s a faith thing. FTL travel would, on one level, would be a state of grace for Homo sapiens. We’d avoided self destruction and were able to apply genius to the problem.
I wonder how people in year 1845 would have ranked future technologies that would be enough to destroy entire cities by flying above them 100 years later.
Thanks for another fascinating video. I go for Draco nuclear rocket. We use nuclear power for the good and bad. If used for peaceful space purpose, and its here right now, would go to perfect that towards the theoretical limit.. Chemical rockets didn't wait for nuclear ones and are doing a good job, time for next step.!
Humans must not be complacent. We must not continue to leave all our eggs in one basket. We must explore other planets and stars, other systems which we may colonize eventually. To do this we must explore the Cosmos with some kind of a robotic starship to find out what is out there, and what challenges we will face in our search for another Home. Thank you, Dr. Kipping for showing us the possibilities.
Agreed. I certainly hope we do the right things for own home planet - pollution, climate, etc - but even if we do, most of the habitable time of Earth’s surface is gone by. Our ancestors spent those long billions of years crawling around instead of solving equations. People are laughing it off now, but there have been several times when large space rocks have registered a nontrivial chance of striking us, only to be later ruled out. How long can we keep rolling lucky 7’s?
@@OOL-UV2Don't worry, the Earth's biosphere is _staggeringly_ resilient, as is the life that clings to its surface! There is simply *no* cataclysm that would make Earth "uninhabitable". The Deccan Traps eruptions that lasted _millennia_ poisoned the atmosphere to levels that make our feeble attempts look meaningless, yet life continued. The KT strike was "bad", but basically irrelevant in the long-run. Humans will persist though quite honestly _anything_ the universe will throw at the Earth. That said, it may be a cycle of "rediscovery" ("knocked back to the stone age", as it were), but the huge benefit is that humans are long-past the cognitive revolution, so millennia of prior development is already "done". Basically, humans are just "noise" in Earth's biome, we are irrelevant.
The worst problem of all is our ridiculous and cosmically disrespectful lifespan. If we could stop aging, most of the problems that we consider now for interstellar travel will end. Stop aging, or slowing it down by hundreds of times, is perfectly possible, and we could have right now much more research into it... but unfortunately we don't. My choices for my sci-fi novel was laser sail to accelerate, anti-matter to decelerate and anti-aging and cryosleep for the crew.
What do you mean we could have put much more research into it?! People have been researching that exact topic for as long as civilization has existed. There's records of nearly every great leader of the ancient world seeking out the wisest men in their lands to discover the key to eternal life. Every year billions are invested into life extending medical research. In fact I could argue that no other subject in all of human history has been researched as extensively as prolonging life has been. We don't have an answer to anti aging today because it is a really difficult problem to solve, not because we haven't been looking hard enough.
I have often wondered if we really require a rocket for space exploration. It might be able to use a laser to sculpt a simple object in another solar system using material already present there, which could then be manipulated into something more complex? A future, highly advanced civilization could potentially apply this concept to make probes in other suns. This approach would involve several key elements: 1) Using directed light beams over vast distances to interact with and manipulate matter. 2) Utilizing in-situ resources found in other solar systems as raw materials. 3) Developing a design that could be made simply that could there create an increasingly complex object. While this concept is far beyond our current technological capabilities, it represents an intriguing possibility for future civilizations with significantly advanced scientific understanding and engineering prowess. If feasible, such a method could potentially overcome many of the challenges associated with traditional space travel, including the need for physical transportation of materials and equipment across vast cosmic distances.
The inherent problem in this concept relies on the fidelity of the beam(s) and the energy required to maintain usable beams, the inherent uncertainties in telemetry and control due to relativistic time dilation of the target body and the simple lag in response time due to the immense distances involved. Also the optical physics of lasers means that even in naked space the laser light although maintaining coherency and wavelength will spread out making the effective intensity of the light beam much less than a flash light.
Solar sails?! I've always read that as a practical matter they're not useful much beyond Mars' orbit, because the Sun's solar wind becomes too attenuated? And laser sails? That will require some pretty fancy lasers there? But a nice array of possible options. Warmest compliments. Thank you, sir. :)
If you want to launch a solar sail on an interstellar mission, you should actually start by sending it towards the sun. A very lightweight solar sail that starts very close to the sun can reach a pretty high velocity, far beyond what is practical to achieve by chemical rockets or nuclear thermal rockets.
So with that laser sale are they just going to shoot it with the laser once? I mean once that thing gets so far away will the laser still be able to hit it or are they going to be able to get it going to 20% the speed of light before it gets too far away? Or are they going to have some kind of lasers in space too? That seems kind of crazy shooting lasers from the ground at a ball a very long way away
Lasers have to stay on all the time. You can put giant mirrors around the sun to create simple lasers from the size of cities to countries that will stay focused for billions of kilometers.
From the ground and for as long as you want. There's basically no limit to how many ground based lasers we could build. The probe will be accelerated - get as crazy as you like.
The old Echo and Echo 2 satellites exhibited influence from light pressure even though they weren't designed for it. By far the largest problem with the laser light sail would be the gigawatt lasers. The largest continuously operating lasers built (and only ran for a handful of seconds at a time) were MIRACL an ABL. Big, heavy, chemical lasers that only produced single-digit megawatt power. Solidstate lasers, being investigated for military use, are only up to the low hundreds of kilowatts. And then there are the military implications of gigawatt lasers. Have you ever heard of the nuclear salt water rocket? See "The Nuclear Salt Water Rocket - Possibly the Craziest Rocket Engine Ever Imagined." (That's the title of Scott Manly's video on it.)
Your bias aside the Halo Drive should be D tier. 1. You need a Black hole and unless the black hole is in the inner solar system we're shit out of luck because the crew would be dead before they got to it. 2, and 3. There would have to be a black hole close to the target destination otherwise it's a one way trip. Even if you got to it you'd need a metric shit ton of radiation shielding which increases the costs significantly. If we assume Planet IX is a primordial black hole and we had a drive capable of getting to it in a matter of weeks, at most months, then yes it would be S tier. But we don't so its feasibility is zero, it's cost is extraordinarily high and for obvious reasons hasn't even had any testing unlike anything in C-tier above. It belongs in D, or elevate the rest of D.
You're missing both #1 fission fragment rockets using thin aerogel holders (somewhat related to fission sails but not the same at all) and a #2 or #3 electrostatic sails.
good list but you left out the most obvious way. the intergalactic uber system. alien space craft comes to earth and picks us up and takes us to wherever we can afford to go :)
Almost all the methods described are within the bounds of the known laws of physics. A few, such as solar sails, nuclear thermal rockets and pulse drives, have been tested. The Alcubierre drive is theoretically possible, but requires negative mass to work. So far as we know, negative mass does not exist, so anything that uses it is dead in the water.
Not true. Chemical rockets have been tested for more than 100 years. Ion thrusters have been used on spacecraft for decades. Nuclear Thermal Propulsion has been tested for 75 years and some prototypes are ready to launch. Solar sails have been tested and the starshot mission using directed energy beams to reach Alpha Centauri are in a late development stage. Vasimir rockets have been heavily studied and engineered. We only lack the money and will to try these ideas. They are not tropes but in fact the means for our species to discover the Galaxy.
I've long thought that a combination would be best. Chemical rockets launched from the Moon for greater escape velocity, several years of gravity assists, solar/laser sail, perhaps with lasers forward deployed to other moons or asteroids, then once beyond their effective range, switch on an ion drive. Yes, it would require many launches overall, but if it gets humans to other star systems, it would be totally worth it. I'd like to hear your thoughts on this.
Super Intelligent AI will ultimatly make the trip. As Arthur C. Clark wrote in his classic Childhood's End, "The solar system you may one day possess, but the stars are not for man."
To be practical, FTL would need to utilize some kind of "Physics short cut" like Warp drive. If we accept the up and coming HUT Physics extension of string theory (HOLOGRAPHIC Universe Theory) a new concept of reality wherin there is a " HIGHER Reality" where ALL particles exist but no space as such. Where our perception interprets the particle wave attributes as points in a (quasi-Illusionary) 3D universe-- our "LOWER reality" We need only find a way to detect and change the wave attributes of our ship's (and bodies) particles to match that of another part of space, even light years away, then "ZAP! we could INSTANTLY jump to that location. HUT is based on David Bohm's theory of how quantum Entangled particles have FTL Commnication ("Spooky action at a distance") Michael Talbot's "The Holographic Universe" is full of evidence for HUT.
missed out solar thermal rocket, use a reflective dish focus sunlight to increase the exhaust temperature (and thus the exhaust velocity) MUCH better than nuclear, and solar sails. not sure why people don't talk about it more as its simple science. energy from solar sail + rocket fuel as mass. = massive delta v.
On the sails. I've only heard it fleshed out once really but you could potentially solar soar not just have a passive parachute, soaring allows you to fly many times faster than the wind I find the idea fascinating.
How can a gravity slingshot confer extra energy~? Surely you gain speed as you approach then lose that gain as you leave the orbit gravitational influence of that planet?
You are correct: if you "slingshot" a spacecraft past a planet, the spacecraft receives no net energy gain from the planet's gravity for exactly the reason you cited. However, in addition to gravitational energy, the planet possesses kinetic energy of orbital motion. It is this orbital kinetic energy that the spacecraft uses to increase its speed. In effect, some of the planet's orbital kinetic energy is transferred to the spacecraft, which causes the spacecraft to move faster. (During the slingshot maneuver, the radius of the planet's orbit decreases, but because the planet is enormously more massive than the spacecraft the change in radius is undetectably small.) Hope this helps!
@@schroedingersdog7965I'll just add that slingshot manoeuvres can also be used to decelerate a spacecraft. It's being used by the current Mercury mission.
Antimatter is like the ultimate battery and probably very inefficient to create on Earth and therefore would probably not be the first item to be made from any excess energy created onboard a ship.
Wasn't there a paper published about anti-matter being generated by high speed particle collisions above our atmosphere in the magnetosphere? If my memory is correct it was enough to be a kind of "anti-matter mine" if you could figure out how to put it in a magnetic bottle without it reacting with matter.
I’ve always believed that the effort required to take humans into interstellar space would be better spent making things work better for us locally. Fix the earth, mine the solar system, hopefully find ways to live in the outer solar systems so we can survive the sun going red giant.
I love the idea of the greatest wonder of this millennium being a giant crewed interstellar mission. Thanks for the inspiring insight as always, David.
I hope Breakthrough Starshot can be done sometime this century. True, this only just sending a tiny probe. Or a continuous series of them. Sending humans is much more challenging. We need to start thinking in terms of centuries. Just as we might have to set up bases on the moon, before we do similar on Mars, ... we probably will have to be able to master our own solar system, before going interstellar. It's one step at a time. It means having mastered the building large orbital mega-structures. This means building power beaming stations that harvest energy from the sun. This forms the initial infrastructure. The other technology to master is anti-matter generation (or collection), out in space. When the foundation has been mastered, one can begin to send larger probes to the nearest stars. A.I. will probably be advanced enough at that time, to represent our values, our desire for exploration and understanding. They will be the next "humans". The interstellar ship can be accelerated by a laser (or other power beaming) infrastructure. The deceleration can be handled by some kind of anti-matter catalyzed fission or fusion.
So what do we think about Warp travel from Warhammer 40k? Pros: >Compatible with most other forms of space travel, as it's an augmentation to the space you're traveling through, rather than propulsion. >Exposure to the Warp may result in super cool psychic powers! >Protected from tyranids, orcs, and the looser tau. Cons: >Hell. The Warp is literally Hell. >Potential heracy. >Those psychic powers my expose you to a fate worse than death.
We are already on a spaceship (the earth) that is traveling at 720,000km per hour. I think we should just focus on extending our lifespans so we can enjoy the ride around the galaxy
Real question: how are we producing antimatter with the lhc since we haven't even found, observed directly, studied or understand antimatter yet? Have I missed something? You are saying that if we had 100 trillion to spent we would have in our hands a measurable amount of antimatter?
