Developing propulsion technology to reach 0.1c velocity will move the needle on interstellar propulsion from impossible to just barely feasible. Although that is at least 100-200 years away, we can absolutely start expanding into our Solar System, starting with nearby bodies, like Moon and Mars.
> Developing propulsion technology to reach 0.1c velocity will move the needle on interstellar propulsion from impossible to just barely feasible
More than barely. "A 40-year one-way interstellar flyby mission to the nearest stars will require a relativistic spacecraft speed in excess of 6000 AU/yr (i.e., > 0.1c)" [1].
That means, practically speaking, nuclear-fusion, antimatter-annihilation and directed-energy propulsion. All of which are TRL ≤ 2.
My bet would be on fusion propulsion. It's inherently easier than fusion power since you don't need to bother converting the energy to electricity. That said, solar sails [2] and directed-energy anti-drone weapons [3] are seeing quiet progress.
Nobody debates this. The point is that 0.1c propulsion is not necessarily 100+ years away. And its 40-year transit time is not "barely feasible," it's comparable to present deep-space mission timelines [1].
However, travel at 0.1c is not needed for the Fermi Argument to bite. Much slower speeds would allow a colonization wave to sweep a galaxy in time << the age of the universe.
The comment by Benjamin Stockton on the article page is spot-on:
>I just wonder if humanity’s adventurous nature is leading us away from a proper focus on the sustainability of our civilization, our specie, and our fragile planetary environment?
But we still need spaceflight at least for planetary defense against asteroids, mining asteroids(so we don't have to mine Earth), etc.
Not only is that comment a false dichotomy (we can both explore space and make humanity more sustainable at the same time), it also presumes that space exploration and sustainability are at odds with one another and not synergistic.
Humans, simply by existing on Earth, have a huge and often negative impact on the environment. If we could somehow shift the human population off Earth, either by terraforming planets (like Mars) or creating artificial space habitats, it would have a huge positive impact on Earth's environment. We don't currently have the technology to do so - we would need space elevators to feasibly move humanity off Earth - but that doesn't mean we should move our attention away from space in the meantime.
The most compelling economic reason to pursue the technology of asteroid mining (at least as far as Earth's gravity well is concerned) is not to ever actually launch any serious asteroid mining operations, but rather to fool those who own gold into believing that you have the capability to devalue gold at your whim, and thereby accept a small ransom to not go asteroid mining.
> What resources are on asteroids that justify the energy expenditure to get from space and back?
With chemical rockets, not much.
With "a propellant-less propulsion propulsion system such as solar sails or electric sails," bringing water (propellant) to low-earth orbit starts making sense [1], as does mining platinum, but only if "the quantity of platinum from space would substitute an equal quantity of terrestrial platinum," i.e. moving heavy industry off the Earth's surface [1].
Given asteroid-mining profitability is dominated by "the throughput rate, which depends on the mining process," it's possibly to see a path to certain rare-earth minerals becoming profitable to mine in space if environmental controls on Earth are tightened while constant-thrust propulsion technologies advance.
Just skimmed but does this answer the question of getting to and from the surface of earth? Or are we just stockpiling platinum in LEO for some reason?
The energy involved in chemical rocketry is actually not that much. Getting a kilogram to LEO is roughly as expensive (in energy) as flying it to the other side of the world in an airliner. Getting stuff back from an earth-crossing asteroid can also be very cheap energetically, with very small delta-V (if one is willing to wait long enough).
"What resources are on asteroids that justify the energy expenditure to get from space and back? Can't be many of them..."
I suggest re-framing the the question as the cost of preserving the objectively limited and to the best of our knowledge singularly unique in the Universe resource, which is the surface of Earth.
Acquiring resources that do not deplete or spoil the future of life on this planet should be in everyone's best interest.
Yeah no. Unless someone can answer basic questions like “what even comes close to net positive in energy expenditure to mine elsewhere,” then this is just a cover story.
The reality is that saving our environment will be a whole set of difficult and profoundly boring solutions to real, known problems.
Would be cool if we could solve it with badass rockets, explosions, big noises, and adventure, but the complete lack of even remotely convincing answers to first order questions on how this actually works belies the fact that it doesn’t. It makes no sense.
We need to develop better plastics, proteins, and pesticides. Not send protein blobs to other planets because it looks cool in sci fi movies.
> We need to develop better plastics, proteins, and pesticides. Not send protein blobs to other planets because it looks cool in sci fi movies
The reality is more people get passsionate about working on things that look cool in sci fi movies than developing plastics, proteins and pesticides for a mediocre paycheque. This lesson--that the path to groundbreaking technologies is through inspirational moonshots, not committees prescribing what is and isn't necessary--is so thoroughly repeated throughout history that it's a wonder we keep missing it.
Groundbreaking technologies are not created via moonshots. They’re created by decades of slog. Moonshots can launch from an unremarkable platform of slog, but the slog had to happen. You just cannot speedrun the vast majority of questions that need to be answered to power a breakthrough.
That’s why I’ll question glory-chasers who want to sit on the rocket but can’t take a few thousands of pay cut to stare for a few years at a true problem that needs solving.
Our species’ actual heroes are those who powered through the slog.
I don’t know, GPS is quite useful, Landsat is too, along with the various other Earth imaging satellites and systems like modis and sentinel-2. Sure is good having food. Weather forecasts are nice. It’s also quite convenient to be able to use space based data services. It’s also useful for power grids to know when they’re about to be whacked by a CME. I’m sure sailors on sinking ships appreciate being rescued.
But sure, we should solve all the problems on earth with one hand tied behind our backs until we can launch any more rockets.
Our civilization has been driven by expansion. Without it we'd probably collapse into a neurally-connected well-organized ant colony without need for further technological/social/economic progress (which would naturally select/cull out corresponding features in our brain). And, i'd guess that is possible one of the forms of the Great Filter stopping many civilizations.
At 53 and good health, i'm contemplating that my end in 30-40 years would be me buying a one way to Mars and just exiting the habitat out without suit after enjoying a dinner with a Martian sunset view, breaking, even in such a small way, the chains of "We come from the earth, we return to the earth" :)
That's a truly awful way to die (all your fluids and gases suddenly surging through your tissue).
Seems much easier to reframe the "chains" of earth into acceptance of a remarkable cycle that we're privileged to get a glimpse of from the inside and just die happily here with your loved ones.
> Seems much easier to reframe the "chains" of earth into acceptance of a remarkable cycle that we're privileged to get a glimpse of from the inside and just die happily here with your loved ones
This works for most people. Most humans didn't leave Africa or Mesopotamia or the Old World, either originally or in the Age of Exploration, and most Americans today don't have a passpport.
That is about my point - i want to get as far as possible from such a philosophy as it is taking over the civilization. I lived under similar philosophy in USSR and, as long as it is up to me, i'll be trying to put a distance in all senses.
>To get around thousand-year generation ships, we are examining some beamed energy solutions that could drive a small sail to Proxima in 20 years.
The odds of a spacecraft hitting a single particle of dust while in space are 100%.
A spacecraft hitting a single particle of dust at 0.2c will impart tens of millions of joules into the body of the spacecraft, the equivalent of getting hit with hundreds of pulses from the most powerful laser ever created by humanity-- simultaneously.
Or concentrating several kilogram's worth of TNT into the size of a particle of dust and detonating it.
Ten megajoules sounds like a lot, but a single kilo of TNT produces about 4 megajoules of energy. And the size of particles of dust and how often you’re likely to hit one in the interstellar medium is quite speculative.
> the size of particles of dust ... in the interstellar medium is quite speculative
Technically yes. I think there's a significant variety of sizes of dust or larger-than-dust particles in interstaller medium but I don't really have much to back that up.
> how often you’re likely to hit one in the interstellar medium is quite speculative.
Also technically yes. But unless you can map every single particle of dust, and their trajectories, I think the risk is absolutely real.
Most of the designs for a system like this are "chip" designs where a single 1cm x 1cm silicon wafer is towed by the sail.
This design prevents the need for lasers so large that they create enough ozone to kill the entire human race.
The contents of the chip vary, based on who is speculating, but tend to contain exotic, uninvented, circuitry capable of both harvesting energy from the laser and doing "something" of use besides zipping by the target at 0.2c deaf, dumb, and blind. Sometimes it's even an AI-enhanced swarm! (Shoulda figured out how to work blockchain in there, post-doc guy)
Regardless, during the 40 trillion kilometer voyage to Proxima Centauri, that 1x1cm silicon wafer (and the sail) will hit space dust, and numerous other atoms and molecules (including carbon rings) because empty space... isn't.
So it passes through the sail and then hits the spacecraft attached to the sail. Now what? kaboom? small holes in the hull would not be good for the occupants.
Are there any real proposals that deal with this issue for a vehicle that would carry humans and go fast? Something that's not "energy shields".
Edit to add: we basically understand the physics of accelerating something to a high speed, what it would need to be made from, etc., afaik all within the realm of possibility- if we could gather and direct that much energy and then wait long enough to decelerate at the other end.
It seems like the questions that are completely unaswered are: keeping people alive and healthy for that long, and how the ship could survive if it hit something.
"A 0.1 µm interstellar dust grain (≈10⁻¹⁴ kg) striking a spacecraft at 0.2 c carries ≈20 J of kinetic energy—millions of times below “tens of millions of joules.” Reaching 10–50 MJ would require a ≈0.14 mm grain (≈10 µg), vastly rarer than ordinary dust, and even that impact equals only a few shots from the world’s highest-energy laser (~2 MJ per pulse), not “hundreds.”"
I used something something 10^-10 for my dust. To reach ~50MJ.
As far as the laser goes, ~2MJ is the total output. Energy that reaches the fuel pellet due to inefficiencies throughout the path of the laser, the actual "hitting power", is hundreds-ish kJ.
alternatively you ionize that particle, may be make in into plasma by laser for ease of "digestion" down in the engine, direct in into the engine where it is used as working mass for your ion thruster, kind of similar to scramjet.
As far as i see with today's tech - like Starlink's ion thruster + classic nuclear reactor - we can get to 300km/s in about 4 stages. Straightforward improvement of ion thrusters - mainly voltage increase and associated engineering (which will immediately happen once we start flying to Mars and beyond as ion thruster currently our best/fastest option inside the Solar system) - can get us to 1000-2000km/s, i.e. under 1000 years to Alpha Centauri (that for a large populated spacecraft, and for just tiny probe to announce our existence (and to send back photos which we'd receive using Sun's gravitational lensing) we can do even better). And using interstellar gas and dust scramjet-style will improve on those numbers (as such ship is mostly limited by the working mass it starts with while the reactors would be able to continue produce the energy much longer).
> alternatively you ionize that particle, may be make in into plasma by laser for ease of "digestion" down in the engine, direct in into the engine where it is used as working mass for your ion thruster, kind of similar to scramjet
This is a Bussard ramjet [1]. The interstellar medium is too thin to make it work. (Maybe we'll find the husk of an ancient ramjet from an earlier era of the universe floating around one day...)
> those of us with an interstellar bent naturally start musing about ‘sundiver’ trajectories, using a solar slingshot to accelerate an outbound spacecraft, perhaps with a propulsive burn at perihelion. . The latter option makes this an ‘Oberth maneuver’ and gives you a maximum outbound kick.
You can't do a solar slingshot like you can with (say) Jupiter because the sun is essentially at rest with respect to the rest of the solar system. You could still do an Oberth manoeuvre.
If you start in our solar system this doesn't help. You could do a gravity assist from a planet to help with an interstellar trip (like the Voyagers) but not a gravity assist from the sun, starting from one of 'our' planets.
> could do a gravity assist from a planet to help with an interstellar trip (like the Voyagers) but not a gravity assist from the sun, starting from one of 'our' planets
Of course you can. Galileo, Cassini-Huygens and Giotto are Earth-launched spacecraft that used Earth for a gravity assist. If you need to accelerate with reference to the galaxy, you can use the Sun’s motion through it to slingshot.
If you unfurl a solar sail after perihelion, presumably you get more energy while nearer the sun, giving more of a "kick", and lower in the gravity well (would oberth still apply for solar sail)
Your speed once you get to 1AU would I assume be far higher than if you had simply started at Earth
But getting to the sun in the first place (from Earth) is a massive hassle as you have to lose the Earth's significant orbital speed to 'fall' inward [0]. Perhaps better just to use that fuel to head out. Operating a solar sail really close to the sun would also be challenging because of the massive heat.
The only way I can see hope for spreading terrestrial life through the galaxy is to send tiny spacecraft. The spacecraft can survey what it finds and send the information back to earth. Earth can send back instructions to the nanobots on the spacecraft to build what is necessary from local materials, and then build life to inhabit it.
You first have to build the perpetual motion engine and the reactionless drive.
Current thinking is quite hostile to doing the work. You might not be able to build the things you think you can. You certainly won't build the things you think you can't.
There was a time when there was nothing (European) in the entire New World. There was a time when there was nothing known (to the US) about what was in most of the Louisiana Purchase. There was a time when there was nothing (European) in, say, Ohio. And then Nebraska. And so on.
There was literally nothing there? Why go all that way? To see what was there. And then to make something there.
[Edit, because I'm rate limited: No, interstellar space is something to cross, to get to stellar space. You think the New World was rich? How about a whole solar system of untapped resources?
There is many times more water in gas giant moons than on Earth. If we develop the technology needed to make a multi-generation ship we also have the technology to make deep space habitats - enough for trillions or quadrillions of people.
Just imagine the economic output of a civilisation a million times the size of ours.
No there wasn't. There was a whole continent of untapped resources.
You can argue that the solar system is a lot of untapped resources too. Harder to extract than sailing a piece of wood across an ocean growing some food, and killing the people who are already there. Harder than colonising Antarctica or the surface of the sea too, but there are resources - not just minerals but solar energy too.
But interstellar space? Beyond the Oort Cloud? There's no evidence of anything other than perhaps some very sparse dust. That is nothing, and (jokes aside) completely incomparable to Ohio.
All life on Earth is going die. Humanity has never been content with staying put, why would we start now? And what do you mean "literally nothing there"? The universe has a loooooot of stuff in it.
By "literally nothing there," I mean there's literally nothing for us. Three stars and a few Earth-sized planets in the habitable zone that are, more than likely, uninhabitable by humans. There's nothing there worth going all that way for.
I like sci-fi as much as the next person but the reality of the situation, it seems to me, is that the universe is mostly empty, vast, and inhospitable to human life.
The difference between a multi-generational interstellar ship and a self-sustaining space colony is the engine. They wouldn’t need inhabitable planets - they would need raw materials to build more ships and habitats.
I’m not sure that after spending a lifetime in an ample space colony its inhabitants would feel nostalgic of the time we spent sitting on round rocks cooking around a star.
>Tragula's wife used to complain to him about the utterly inordinate amount of time he spent staring out into space, or mulling over the mechanics of safety pins, or doing spectrographic analyses of pieces of fairy cake. She would often tell her husband to have some sense of proportion, sometimes as often as thirty-eight times in one day. In response to her pleas for him to find some perspective, he built the Total Perspective Vortex.
>Into one end he plugged the whole of reality as extrapolated from a piece of fairy cake, and into the other end he plugged his wife: so that when he turned it on she would see in one instant the whole infinity of creation and herself in relation to it. To Trin Tragula’s horror, the shock completely annihilated her brain...
~Douglas Adams, The Restaurant at the End of the Universe
Ask ten different scientists about the environment, population control, genetics, and you'll get ten different answers, but there's one thing every scientist on the planet agrees on. Whether it happens in a hundred years or a thousand years or a million years, eventually our Sun will grow cold and go out. When that happens, it won't just take us. It'll take Marilyn Monroe, and Lao-Tzu, and Einstein, and Morobuto, and Buddy Holly, and Aristophanes, and - all of this - all of this - was for nothing. Unless we go to the stars
>Humanity has never been content with staying put, why would we start now?
For whatever reason, humanity's attitude in this regard has changed drastically in the last century. We can't even bother to make the next generations, and a shrinking population eventually (quite quickly, really) shrinks to zero. Not only do they want to "stay put", they want to lay down and die.
The steelman counterargument is that focusing resources on extraplanetary colonies at the expense of the one habitable planet within reach will hasten humanity's destruction. How are you going to make an Eden on Mars if we can't even make an Eden on Earth? The only large-scale planetary engineering in humanity's history is Veniforming its home world.
>The steelman counterargument is that focusing resources on extraplanetary colonies at the expense of the one habitable planet within reach will hasten humanity's destruction.
That doesn't seem like a strong argument to me. It seems like a distraction from the crowd that would save the planet by extinguishing humanity if that's what it took. Though what value the planet might have with all of us gone I leave as an exercise for the reader.
The first priority of any society that wants to continue to exist into the future must always be to make the next generation. If you do not do this, or if you just leave the task to others hoping that someone else will do it, then you are behaving in a way that will in all probability lead towards there being no next generation sooner or later. The "global warming is the apocalypse" movement constantly talks about how the best way to reduce your carbon footprint is to have no children.
>The only large-scale planetary engineering in humanity's history is Veniforming its home world.
So it is claimed, but from my point of view it looks very much as if it's intent on making itself extinct through fertility decline. But at least carbon dioxide levels will return to normal, eh?
More than barely. "A 40-year one-way interstellar flyby mission to the nearest stars will require a relativistic spacecraft speed in excess of 6000 AU/yr (i.e., > 0.1c)" [1].
That means, practically speaking, nuclear-fusion, antimatter-annihilation and directed-energy propulsion. All of which are TRL ≤ 2.
My bet would be on fusion propulsion. It's inherently easier than fusion power since you don't need to bother converting the energy to electricity. That said, solar sails [2] and directed-energy anti-drone weapons [3] are seeing quiet progress.
[1] https://ntrs.nasa.gov/api/citations/20200000759/downloads/20...
[2] https://www.nasa.gov/mission/acs3/
[3] https://en.wikipedia.org/wiki/Silent_Hunter_(laser_weapon)
Nobody debates this. The point is that 0.1c propulsion is not necessarily 100+ years away. And its 40-year transit time is not "barely feasible," it's comparable to present deep-space mission timelines [1].
[1] https://science.nasa.gov/mission/voyager/
>I just wonder if humanity’s adventurous nature is leading us away from a proper focus on the sustainability of our civilization, our specie, and our fragile planetary environment?
But we still need spaceflight at least for planetary defense against asteroids, mining asteroids(so we don't have to mine Earth), etc.
Humans, simply by existing on Earth, have a huge and often negative impact on the environment. If we could somehow shift the human population off Earth, either by terraforming planets (like Mars) or creating artificial space habitats, it would have a huge positive impact on Earth's environment. We don't currently have the technology to do so - we would need space elevators to feasibly move humanity off Earth - but that doesn't mean we should move our attention away from space in the meantime.
With chemical rockets, not much.
With "a propellant-less propulsion propulsion system such as solar sails or electric sails," bringing water (propellant) to low-earth orbit starts making sense [1], as does mining platinum, but only if "the quantity of platinum from space would substitute an equal quantity of terrestrial platinum," i.e. moving heavy industry off the Earth's surface [1].
Given asteroid-mining profitability is dominated by "the throughput rate, which depends on the mining process," it's possibly to see a path to certain rare-earth minerals becoming profitable to mine in space if environmental controls on Earth are tightened while constant-thrust propulsion technologies advance.
[1] https://arxiv.org/pdf/1810.03836
Yes. (Deöbiting from LEO is cheap, like 90 m/s for the Space Shuttle, because you can use the atmosphere.)
The energy involved in chemical rocketry is actually not that much. Getting a kilogram to LEO is roughly as expensive (in energy) as flying it to the other side of the world in an airliner. Getting stuff back from an earth-crossing asteroid can also be very cheap energetically, with very small delta-V (if one is willing to wait long enough).
I suggest re-framing the the question as the cost of preserving the objectively limited and to the best of our knowledge singularly unique in the Universe resource, which is the surface of Earth.
Acquiring resources that do not deplete or spoil the future of life on this planet should be in everyone's best interest.
The reality is that saving our environment will be a whole set of difficult and profoundly boring solutions to real, known problems.
Would be cool if we could solve it with badass rockets, explosions, big noises, and adventure, but the complete lack of even remotely convincing answers to first order questions on how this actually works belies the fact that it doesn’t. It makes no sense.
We need to develop better plastics, proteins, and pesticides. Not send protein blobs to other planets because it looks cool in sci fi movies.
The reality is more people get passsionate about working on things that look cool in sci fi movies than developing plastics, proteins and pesticides for a mediocre paycheque. This lesson--that the path to groundbreaking technologies is through inspirational moonshots, not committees prescribing what is and isn't necessary--is so thoroughly repeated throughout history that it's a wonder we keep missing it.
Groundbreaking technologies are not created via moonshots. They’re created by decades of slog. Moonshots can launch from an unremarkable platform of slog, but the slog had to happen. You just cannot speedrun the vast majority of questions that need to be answered to power a breakthrough.
That’s why I’ll question glory-chasers who want to sit on the rocket but can’t take a few thousands of pay cut to stare for a few years at a true problem that needs solving.
Our species’ actual heroes are those who powered through the slog.
The slog is almost always in pursuit of a moonshot. The moon justifies the slog. We don’t slog for the sake of it.
But sure, we should solve all the problems on earth with one hand tied behind our backs until we can launch any more rockets.
At 53 and good health, i'm contemplating that my end in 30-40 years would be me buying a one way to Mars and just exiting the habitat out without suit after enjoying a dinner with a Martian sunset view, breaking, even in such a small way, the chains of "We come from the earth, we return to the earth" :)
Seems much easier to reframe the "chains" of earth into acceptance of a remarkable cycle that we're privileged to get a glimpse of from the inside and just die happily here with your loved ones.
This works for most people. Most humans didn't leave Africa or Mesopotamia or the Old World, either originally or in the Age of Exploration, and most Americans today don't have a passpport.
The acceptance would have me still in Russia :)
Novelty, for one.
Obviously one is free to want that. When I think of the opportunity costs involved, it seems repugnant to be honest. The opposite of glorious.
And art and scientific endeavour and exploration and possibly all the things that make us human, but sure.
The odds of a spacecraft hitting a single particle of dust while in space are 100%.
A spacecraft hitting a single particle of dust at 0.2c will impart tens of millions of joules into the body of the spacecraft, the equivalent of getting hit with hundreds of pulses from the most powerful laser ever created by humanity-- simultaneously.
Or concentrating several kilogram's worth of TNT into the size of a particle of dust and detonating it.
Technically yes. I think there's a significant variety of sizes of dust or larger-than-dust particles in interstaller medium but I don't really have much to back that up.
> how often you’re likely to hit one in the interstellar medium is quite speculative.
Also technically yes. But unless you can map every single particle of dust, and their trajectories, I think the risk is absolutely real.
Most of the designs for a system like this are "chip" designs where a single 1cm x 1cm silicon wafer is towed by the sail.
This design prevents the need for lasers so large that they create enough ozone to kill the entire human race.
The contents of the chip vary, based on who is speculating, but tend to contain exotic, uninvented, circuitry capable of both harvesting energy from the laser and doing "something" of use besides zipping by the target at 0.2c deaf, dumb, and blind. Sometimes it's even an AI-enhanced swarm! (Shoulda figured out how to work blockchain in there, post-doc guy)
Regardless, during the 40 trillion kilometer voyage to Proxima Centauri, that 1x1cm silicon wafer (and the sail) will hit space dust, and numerous other atoms and molecules (including carbon rings) because empty space... isn't.
In any case, we should launch more than one.
Edit to add: we basically understand the physics of accelerating something to a high speed, what it would need to be made from, etc., afaik all within the realm of possibility- if we could gather and direct that much energy and then wait long enough to decelerate at the other end.
It seems like the questions that are completely unaswered are: keeping people alive and healthy for that long, and how the ship could survive if it hit something.
Whipple shields [1].
> Something that's not "energy shields"
The interstellar medium contains lots of charged particles [2]. Electromagnetic deflection is perfectly realistic.
[1] https://en.wikipedia.org/wiki/Whipple_shield
[2] https://www.space.com/interstellar-space-definition-explanat...
As far as the laser goes, ~2MJ is the total output. Energy that reaches the fuel pellet due to inefficiencies throughout the path of the laser, the actual "hitting power", is hundreds-ish kJ.
the other thought is a space ram jet sucking in particles heard of some idea like this
As far as i see with today's tech - like Starlink's ion thruster + classic nuclear reactor - we can get to 300km/s in about 4 stages. Straightforward improvement of ion thrusters - mainly voltage increase and associated engineering (which will immediately happen once we start flying to Mars and beyond as ion thruster currently our best/fastest option inside the Solar system) - can get us to 1000-2000km/s, i.e. under 1000 years to Alpha Centauri (that for a large populated spacecraft, and for just tiny probe to announce our existence (and to send back photos which we'd receive using Sun's gravitational lensing) we can do even better). And using interstellar gas and dust scramjet-style will improve on those numbers (as such ship is mostly limited by the working mass it starts with while the reactors would be able to continue produce the energy much longer).
This is a Bussard ramjet [1]. The interstellar medium is too thin to make it work. (Maybe we'll find the husk of an ancient ramjet from an earlier era of the universe floating around one day...)
[1] https://en.wikipedia.org/wiki/Bussard_ramjet
You can't do a solar slingshot like you can with (say) Jupiter because the sun is essentially at rest with respect to the rest of the solar system. You could still do an Oberth manoeuvre.
But not with respect to other star systems.
Of course you can. Galileo, Cassini-Huygens and Giotto are Earth-launched spacecraft that used Earth for a gravity assist. If you need to accelerate with reference to the galaxy, you can use the Sun’s motion through it to slingshot.
Your speed once you get to 1AU would I assume be far higher than if you had simply started at Earth
[0] https://www.nasa.gov/solar-system/its-surprisingly-hard-to-g...
Current thinking is quite hostile to doing the work. You might not be able to build the things you think you can. You certainly won't build the things you think you can't.
There's literally nothing there, why go all that way? The distances are so incredibly vast. It seems like we ought to be content with staying put.
“Literally everything is in space.”
There was literally nothing there? Why go all that way? To see what was there. And then to make something there.
[Edit, because I'm rate limited: No, interstellar space is something to cross, to get to stellar space. You think the New World was rich? How about a whole solar system of untapped resources?
That's why people will try to go.]
The hypothetical riches were quite obvious: same stuff we have over here, but not owned by someone yet.
What are they hypothetical riches of outer space?
This is a question we should think about clearly and logically without resorting to stuff like "oh tally-ho the adventure!" type nonsense.
Just imagine the economic output of a civilisation a million times the size of ours.
Then we can use all of that new productivity to start working toward the next rung?
Our economy is not currently throughput limited on water or space so I don’t find this compelling.
No there wasn't. There was a whole continent of untapped resources.
You can argue that the solar system is a lot of untapped resources too. Harder to extract than sailing a piece of wood across an ocean growing some food, and killing the people who are already there. Harder than colonising Antarctica or the surface of the sea too, but there are resources - not just minerals but solar energy too.
But interstellar space? Beyond the Oort Cloud? There's no evidence of anything other than perhaps some very sparse dust. That is nothing, and (jokes aside) completely incomparable to Ohio.
By "literally nothing there," I mean there's literally nothing for us. Three stars and a few Earth-sized planets in the habitable zone that are, more than likely, uninhabitable by humans. There's nothing there worth going all that way for.
I like sci-fi as much as the next person but the reality of the situation, it seems to me, is that the universe is mostly empty, vast, and inhospitable to human life.
I’m not sure that after spending a lifetime in an ample space colony its inhabitants would feel nostalgic of the time we spent sitting on round rocks cooking around a star.
So is the Pacific Ocean for practical definitions of emptiness. You don't got to the empty places.
In fact, technically, there's nothing here. It's all out there.
Jupiter: ~0.095% of the total mass, and ~71% of the non-solar mass.
Saturn: ~0.03% of the total mass, and ~19% of the non-solar mass.
Uranus and Neptune: Contribute a small percentage to the remaining non-solar mass.
All other objects: (inner planets, dwarf planets, moons, asteroids, comets, etc.) account for less than 0.002% of the solar system's total mass.
Your brain mass is about 3 disposable water bottles in weight and we can debate what parts of that are thinking and actually "you".
You are insignificant on the scale of the solar system let alone the universe.
>Into one end he plugged the whole of reality as extrapolated from a piece of fairy cake, and into the other end he plugged his wife: so that when he turned it on she would see in one instant the whole infinity of creation and herself in relation to it. To Trin Tragula’s horror, the shock completely annihilated her brain...
~Douglas Adams, The Restaurant at the End of the Universe
Ask ten different scientists about the environment, population control, genetics, and you'll get ten different answers, but there's one thing every scientist on the planet agrees on. Whether it happens in a hundred years or a thousand years or a million years, eventually our Sun will grow cold and go out. When that happens, it won't just take us. It'll take Marilyn Monroe, and Lao-Tzu, and Einstein, and Morobuto, and Buddy Holly, and Aristophanes, and - all of this - all of this - was for nothing. Unless we go to the stars
That's the fallacy in the given argument.
Might very well be the last question we need to ask ourselves.
For whatever reason, humanity's attitude in this regard has changed drastically in the last century. We can't even bother to make the next generations, and a shrinking population eventually (quite quickly, really) shrinks to zero. Not only do they want to "stay put", they want to lay down and die.
That doesn't seem like a strong argument to me. It seems like a distraction from the crowd that would save the planet by extinguishing humanity if that's what it took. Though what value the planet might have with all of us gone I leave as an exercise for the reader.
The first priority of any society that wants to continue to exist into the future must always be to make the next generation. If you do not do this, or if you just leave the task to others hoping that someone else will do it, then you are behaving in a way that will in all probability lead towards there being no next generation sooner or later. The "global warming is the apocalypse" movement constantly talks about how the best way to reduce your carbon footprint is to have no children.
>The only large-scale planetary engineering in humanity's history is Veniforming its home world.
So it is claimed, but from my point of view it looks very much as if it's intent on making itself extinct through fertility decline. But at least carbon dioxide levels will return to normal, eh?