Japan tests explosion-powered rocket for the first time in space (2021)(autoevolution.com)
autoevolution.com
Japan tests explosion-powered rocket for the first time in space (2021)
https://www.autoevolution.com/news/japan-tests-explosion-powered-rocket-for-the-first-time-in-space-is-a-success-167696.html
72 comments
Yo, I hear you.
Tell me more about the potential of electrohydrodynamic engines. What excites you there?
I want to know whether it would be possible to efficiently ionize air and push it with electromagnetic pulses. It just seems so futuristic, you know?
Tell me more about the potential of electrohydrodynamic engines. What excites you there?
I want to know whether it would be possible to efficiently ionize air and push it with electromagnetic pulses. It just seems so futuristic, you know?
Works for fixed wing planes!
https://youtu.be/IorDYGI1uqc
https://youtu.be/IorDYGI1uqc
But not pushed with electromagnets, yeah?
oh right! that plane is electrostatic rather than magneto fluid dynamic. good point I totally spaced on that one. MHD stuff is super cool tho!
Ya I want to increase the power density of EHD engines too, although to my knowledge nobody has done it yet, at least not publicly. Here's an example of a multi-stage engine by Jay Bowles at Plasma Channel:
https://www.youtube.com/watch?v=nrEBoPYS4ns
Unfortunately, I believe that his design is unlikely to be scalable, since each stage gets less than a linear increase in thrust due to losses. It's like stacking propeller blades. Each stage performs worse as more turbulence is added and the airflow gets less laminar.
IMHO the efficiency comes from the surface area of the anode (the wire). The cathode could be the lifting surface or body of the craft, so isn't that relevant for performance. Foils, pipes, anything works for the cathode. Taken to the limit, the anode might look like a 3D array of point charges, separated by thin insulated wires. Or a mesh with a high surface area to volume ratio. Something that looks more like a big ball of steel wool.
Some experiments have also separated the ionization from the electric field. Like in vacuum tubes, the hot plate can emit electrons regardless of the voltage between anode and cathode. Perhaps a laser could light up the surface of the anode at the exact energy needed to free electrons, I dunno. But I wonder if he's planning to do something similar:
https://www.youtube.com/watch?v=YFkUOPl0tUw
Another problem is that the ions move incredibly fast, potentially faster than the speed of sound, but only drag on the order of 1 in 100 other air molecules with them. It quickly saturates so a linear increase in current gets a sublinear increase in thrust. So an EHD engine is more efficient at lower speed, just like a helicopter prop. That's where creating more ions with more surface area might help. Also pulsed DC might get good airflow with fewer ions, so far the best result I've seen is 886 W/kg, similar to a helicopter:
http://jnaudin.free.fr/html/lftphv.htm
At the end of the day, EHD engines will probably end up working more like drones and balloons than rockets. Although some people have messed with putting the anode in front of a wing for a bit better lift.
Anyway, this is all great and stuff, but people like us on HN are relentless hackers. If I was part of a think tank and found the resources to fund it, I would take these experiments to the limit and build the best possible EHD engine. Maybe try to get to 100 W/kg to start, then shoot for 10, and so on. Which is why I think the Skunk Works or DARPA or someone like that probably built one back in say the 1960s and kept it secret:
https://en.wikipedia.org/wiki/Biefeld–Brown_effect
JP Aerospace was going to build an airship to orbit with their Ascender model, powered by an EHD mesh in front of perhaps an aluminized mylar balloon/cathode:
http://www.jpaerospace.com
That's the only real threat to someone like SpaceX that I know of. Their idea could work, although I suspect that thrust reduces proportionately to the air thinning with altitude. So they'll need a way to gather a larger volume of ions in front of the ship, maybe with a laser or something magnetic, as you suggested.
It would be like building an airfoil 100 times more efficient that anything we have now, so that it could fly at 100,000+ feet (20 miles) at 1/100 atmospheres of pressure the way an airplane flies at sea level. Then gradually ascend to perhaps the Karman line at 100 km (60 miles) by changing the geometry of the airship to fly faster or just use rockets like an RDE or something.
https://www.youtube.com/watch?v=nrEBoPYS4ns
Unfortunately, I believe that his design is unlikely to be scalable, since each stage gets less than a linear increase in thrust due to losses. It's like stacking propeller blades. Each stage performs worse as more turbulence is added and the airflow gets less laminar.
IMHO the efficiency comes from the surface area of the anode (the wire). The cathode could be the lifting surface or body of the craft, so isn't that relevant for performance. Foils, pipes, anything works for the cathode. Taken to the limit, the anode might look like a 3D array of point charges, separated by thin insulated wires. Or a mesh with a high surface area to volume ratio. Something that looks more like a big ball of steel wool.
Some experiments have also separated the ionization from the electric field. Like in vacuum tubes, the hot plate can emit electrons regardless of the voltage between anode and cathode. Perhaps a laser could light up the surface of the anode at the exact energy needed to free electrons, I dunno. But I wonder if he's planning to do something similar:
https://www.youtube.com/watch?v=YFkUOPl0tUw
Another problem is that the ions move incredibly fast, potentially faster than the speed of sound, but only drag on the order of 1 in 100 other air molecules with them. It quickly saturates so a linear increase in current gets a sublinear increase in thrust. So an EHD engine is more efficient at lower speed, just like a helicopter prop. That's where creating more ions with more surface area might help. Also pulsed DC might get good airflow with fewer ions, so far the best result I've seen is 886 W/kg, similar to a helicopter:
http://jnaudin.free.fr/html/lftphv.htm
At the end of the day, EHD engines will probably end up working more like drones and balloons than rockets. Although some people have messed with putting the anode in front of a wing for a bit better lift.
Anyway, this is all great and stuff, but people like us on HN are relentless hackers. If I was part of a think tank and found the resources to fund it, I would take these experiments to the limit and build the best possible EHD engine. Maybe try to get to 100 W/kg to start, then shoot for 10, and so on. Which is why I think the Skunk Works or DARPA or someone like that probably built one back in say the 1960s and kept it secret:
https://en.wikipedia.org/wiki/Biefeld–Brown_effect
JP Aerospace was going to build an airship to orbit with their Ascender model, powered by an EHD mesh in front of perhaps an aluminized mylar balloon/cathode:
http://www.jpaerospace.com
That's the only real threat to someone like SpaceX that I know of. Their idea could work, although I suspect that thrust reduces proportionately to the air thinning with altitude. So they'll need a way to gather a larger volume of ions in front of the ship, maybe with a laser or something magnetic, as you suggested.
It would be like building an airfoil 100 times more efficient that anything we have now, so that it could fly at 100,000+ feet (20 miles) at 1/100 atmospheres of pressure the way an airplane flies at sea level. Then gradually ascend to perhaps the Karman line at 100 km (60 miles) by changing the geometry of the airship to fly faster or just use rockets like an RDE or something.
Awesome! Yes, I’ve wondered whether the very large surface areas of zeppelins could create opportunities. I mean, with solar power, you can have quite a bit of electrical charge on hand— and if there was a cheap & weight-efficient way to generate thrust over a large area, it could be rather powerful.
Consider writing open proposals. You have a great set of knowledge and ideas. It’s easier than ever to get illustrations that make it seem real. Thanks!
Consider writing open proposals. You have a great set of knowledge and ideas. It’s easier than ever to get illustrations that make it seem real. Thanks!
Oh and the reverse also works, generating power from moving ions, which could replace wind turbines someday:
https://www.youtube.com/watch?v=nNp21zTeCDc
https://www.youtube.com/watch?v=nNp21zTeCDc
Right there with you buddy. I spent so much time on the dopamine trip of watching people do cool things a good chunk of my life passed by getting nothing done myself.
Started building things last year and it’s been a blast (and super frustrating and more expensive than i expected but eh, worth it)
Started building things last year and it’s been a blast (and super frustrating and more expensive than i expected but eh, worth it)
At least your views are encouraging and paying the bills for other people who are doing cool stuff
Here's a video that presents the science behind rotating detonation engines; the article was pretty light on detail. This video is at the other end of the spectrum, clearly intended for other researchers in this domain.
Or, if it's over your head (it was for me, at least while trying to wake up), you can still enjoy the pretty damn cool high speed imaging of the detonation waves in this type of engine.
https://youtu.be/Ws4kbgfpKCw?t=310
https://youtu.be/Ws4kbgfpKCw?t=310
Deja YouTube, when you click on a link and find you had watched the first 5 minutes of it two years ago.
No, the link jumps to that point.
Woah, exactly same here! Video starts 5 minutes in, so I watched and left off there some time. Wonder what the reason is there.
The &t=${Timestamp} query parameter links directly to a point in the video
That’s me - that video summarized my dissertation work. I did some follow-on modeling work using neural ODEs that’s pretty neat, too: https://aip.scitation.org/doi/10.1063/5.0063624
Wait. So. I do research in the polar regions and am interested in potential novel power sources for extremely remote environments. Is there any future where this kind of engine could be used for power generation? Say by storage in some capacity? Flywheel. Batteries. Etc. It seems to me it should be possible to detonate\fire when you need to top off your storage but that the design need not be limited to propulsion. Am I crazy? This is so far from my field of work, although I was originally a physicist.
Energy density, ease of transport, robustness, and all sorts of other considerations dominate in an environment that is very hostile. Aside from nuclear power (which we will never get) the future is pretty bleak for us still when compared to the diverse technology available in more "normalcy climates.
Energy density, ease of transport, robustness, and all sorts of other considerations dominate in an environment that is very hostile. Aside from nuclear power (which we will never get) the future is pretty bleak for us still when compared to the diverse technology available in more "normalcy climates.
The title lured me into thinking it would be another Project Orion [https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propuls...] :)
I thought this too. Though there is a treaty (https://en.wikipedia.org/wiki/Partial_Nuclear_Test_Ban_Treat...) which bans nuclear detonations in space.
I remember reading an Isaac Asimov story where aliens learned that we did all our nuclear detonation on the planet’s surface instead of on space and decide that humanity should be quarantined and not allowed into the interstellar society.
Of course living through the decades since Asimov wrote that story, it seems the aliens have plenty of other reasons to keep our species quarantined.
Of course living through the decades since Asimov wrote that story, it seems the aliens have plenty of other reasons to keep our species quarantined.
It's a common trope in sci-fi, but also silly when you consider the scale of space and how radioactive it already is.
And then consider that any civilization capable of interstellar travel would already need to be harnessing energies that make nukes look like firecrackers.
And then consider that any civilization capable of interstellar travel would already need to be harnessing energies that make nukes look like firecrackers.
That's the story "Silly Asses," published in 1958.
Wouldn't the ban not make sense if we only use it in deep space instead of LEO?
At some point in the far future it might make sense to renegotiate that treaty, but for now we're so far from being able to build a practical Project Orion type spacecraft that the issue is moot. And in the meantime there are other nuclear rocket designs which don't rely on explosions and would comply with the treaty. Those engines would be perfectly adequate to send manned missions to Mars and the outer planets, if we were willing to spend a few trillion dollars.
Scott Manley did a video 2 years ago on rotating detonation gun engines, them being 25% more efficient. More bang for your buck?
https://www.youtube.com/watch?v=rG_Eh0J_4_s
I almost did mechanical engineering, in my placement before starting a degree I didn’t start I was working with detonation guns to fire tungsten carbide into machined parts to make them last far longer in nuclear power stations.
That had finished, just work on jet engine blades.
https://www.youtube.com/watch?v=rG_Eh0J_4_s
I almost did mechanical engineering, in my placement before starting a degree I didn’t start I was working with detonation guns to fire tungsten carbide into machined parts to make them last far longer in nuclear power stations.
That had finished, just work on jet engine blades.
It's not clear to me why they avoid talking about specific impulse or exhaust velocity. When you are in space, this is what matters. If you don't increase them, it's meaningless to say the engine has "higher efficiency".
Higher iSP is usually what more efficient means for rockets at least in space.
I always wondered, did we put the nukes on the wrong end of the rockets? I mean a nuclear warhead can cause serious damage, but if you put it behind a rocket for controlled propulsion, we can explore deep space, which is better. Why go to war when we can become space faring instead? It's much more humane, civilized, and less embarrassing as a species.
As I understand , nuclear power wasn't used for space exploration mostly for political reasons. It's considered quite unpopular to put nuclear engines which fly above people heads. There are therefore a lot of regulations for the use of nuclear propulsion, which has discouraged its use for now.
Well, political reasons generally, and the Partial Test Ban treaty in particular. It turns out there's really good reasons to limit the number of bombs detonated in the atmosphere, and for that matter the number of bombs, period.
https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propuls...
https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propuls...
Atomic engines wouldn't really accelerate space development all that much. I don't see a world where telecommunications, computers and robotics advance any faster than the one we're in from a 1960s starting point. And we're only just getting to the point where automated manufacturing is advanced enough that space industry seems like almost maybe viable. Even if atomic engines let people in the 70s put more mass into orbit, they wouldn't really have the tech to do much productive with it.
Plus, a rocket with a nuke on the other end can still destroy a city if you point it in the right direction. There's no such thing as an unarmed spaceship.
Plus, a rocket with a nuke on the other end can still destroy a city if you point it in the right direction. There's no such thing as an unarmed spaceship.
>Why go to war when we can become space faring instead?
Because going to war can benefit you and / or harm your enemies. There's not much to do out in space compared to our home planet.
Because going to war can benefit you and / or harm your enemies. There's not much to do out in space compared to our home planet.
Because space settlement could pose a threat to you guys, I mean the US, and also because of cosmic radiation. Habitats with thick enough shield are way too impractical to launch from down here, and must be somehow constructed in space, which is hard.
Sort of in the same vein, here's a PNAS report [1] of a continuous combustion detonation engine. No circulating detonation wave, no pulses, just steady combustion in a propellant stream fast enough to stabilize the detonation region at a feature in the engine.
Just speculation on my part, but I would think the Isp would be higher than the usual chemical combustion regimes due to higher temperature in the detonation volume. Pretty interesting stuff.
[1] https://www.pnas.org/doi/full/10.1073/pnas.2102244118
Just speculation on my part, but I would think the Isp would be higher than the usual chemical combustion regimes due to higher temperature in the detonation volume. Pretty interesting stuff.
[1] https://www.pnas.org/doi/full/10.1073/pnas.2102244118
> detonation and compression waves at extremely high frequencies (1 to 100 kHz)
Finally spacecraft will be able to produce the characteristic "vvvzzzhzhzh" sound we know from movies like Star Wars. Heard only inside the ship, of course, but likely it will permeate the whole ship while the engine is on.
Finally spacecraft will be able to produce the characteristic "vvvzzzhzhzh" sound we know from movies like Star Wars. Heard only inside the ship, of course, but likely it will permeate the whole ship while the engine is on.
Anyone able to provide some info on why this type of engine might be "better"? Is it's use likely to become widespread? Can it be scaled up to propel larger craft?
The detonation produces higher pressure and temperature, causing higher exhaust gas velocities. More energy in the exhaust means more push from the same amount of propellant. About 15% more. The other yet to be realized in practice advantage is that by eliminating the compressor stages on a rocket engine its construction is simplified, and despite needing a much stronger combustion chamber, it could actually be lighter.
If it can live up to more efficient, cheaper, and lighter then it will certainly see widespread use.
There are bound to be issues with new larger designs, but nothing show stopping is expected.
If it can live up to more efficient, cheaper, and lighter then it will certainly see widespread use.
There are bound to be issues with new larger designs, but nothing show stopping is expected.
RDEs are more efficient than regular rocket engines. Also, a big part of engineering rocket combustion chambers is balancing power with combustion instability, which can cause flame-out at best, and rapid unscheduled disassembly at worse. RDEs lean into that high energy stochiometric reaction to eke out more efficiency. Due to the tyranny of the rocket equation, even a modest increase in efficiency can greatly increase payload to orbit.
Pushing on solid wall is more effective than pushing on air. Shockwaves are effectively momentarily solid air that you could push on. RDE basically uses shockwaves as turbine blades.
(technically I should say "incompressible vs compressible" but you get the imagery)
(technically I should say "incompressible vs compressible" but you get the imagery)
I assume because you can use (mini)nuclear explosions in deep space?
Detonation engines has nothing to do with nukes, it’s just a different way of burning fuel, in a detonation mode/regimen/whatever. Which is I suppose more violent and rapid and efficient, but much more finicky compared to conventional combustion method/type/phenomenon.
Sort of like ramjet vs scramjet difference. “I guess that’s better, if you think it can be done, I don’t know though” thing.
Sort of like ramjet vs scramjet difference. “I guess that’s better, if you think it can be done, I don’t know though” thing.
But the valuable energy density of nuclear doesn’t have a combustion equivalent, right? Only explosions or slow burns.
I believe nuclear “explosions” are slow burns too, just a sun in Earth’s atmosphere out of nowhere has to cause explosion-like phenomena, and equivalence with chemical explosion can be established. In vacuum it will be just a molten ball.
This one uses continuously happening detonation along a circular path, and has little to do with those.
This one uses continuously happening detonation along a circular path, and has little to do with those.
ELI5: why don't they use "tiny nukes", basically engineer a small (less than 10cm/1in) nuclear bombs that explode in a chamber at the back of the space ship?
- Can't make nukes that small (you literally can't fit critical mass in that size I think, afaik smallest developed ever are 155mm artillery shells)
- massive mess if it goes wrong in any way
- putting nukes in space is banned by treaty and would be an ugly precedent
-Japan has committed to not making nukes and has for obvious historical reasons a difficult relationship with the topic.
(If Japan wanted to become a nuclear power, they relatively easily could for a country that doesn't have any, but that would be a major thing and not a side thing of some science project)
- massive mess if it goes wrong in any way
- putting nukes in space is banned by treaty and would be an ugly precedent
-Japan has committed to not making nukes and has for obvious historical reasons a difficult relationship with the topic.
(If Japan wanted to become a nuclear power, they relatively easily could for a country that doesn't have any, but that would be a major thing and not a side thing of some science project)
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I hope they amend the treaty with IAEA being able to enforce things and all. I think we can leave japan out of this too, I don't see why one country is so important.
Isn't 155mm 15cm? Close enough I would say if it was an actual fission explosion.
As for safety, nukes in space are safe and you can launch them using conventional propulsion and use nukes only in space and also launch from point nemo or cook islands so you are at least 3000mi away from large populations.
I get these challenges are real but if the advantage over ion propulsion is great then it sounds like they are worth overcoming.
Isn't 155mm 15cm? Close enough I would say if it was an actual fission explosion.
As for safety, nukes in space are safe and you can launch them using conventional propulsion and use nukes only in space and also launch from point nemo or cook islands so you are at least 3000mi away from large populations.
I get these challenges are real but if the advantage over ion propulsion is great then it sounds like they are worth overcoming.
> you can launch them using conventional propulsion and use nukes only in space and also launch from point nemo or cook islands so you are at least 3000mi away from large populations.
If something goes wrong during the launch and the rocket explodes, isn't that basically exploding a dirty bomb in the upper atmosphere? Is 3000 miles really enough of a buffer zone?
https://en.m.wikipedia.org/wiki/Dirty_bomb
If something goes wrong during the launch and the rocket explodes, isn't that basically exploding a dirty bomb in the upper atmosphere? Is 3000 miles really enough of a buffer zone?
https://en.m.wikipedia.org/wiki/Dirty_bomb
From that article:
> Since a dirty bomb is unlikely to cause many deaths by radiation exposure, many do not consider this to be a weapon of mass destruction.[2] Its purpose would presumably be to create psychological, not physical, harm through ignorance, mass panic, and terror. For this reason dirty bombs are sometimes called "weapons of mass disruption". Additionally, containment and decontamination of thousands of victims, as well as decontamination of the affected area might require considerable time and expense, rendering areas partly unusable and causing economic damage
Since that paragraph is talking about detonation over a populated area, 3k miles away even in the atmosphere I would think wouldn't cause much of an actual harm.
But a solution might be to enrich the radioactive material in a space station in orbit.
Since that paragraph is talking about detonation over a populated area, 3k miles away even in the atmosphere I would think wouldn't cause much of an actual harm.
But a solution might be to enrich the radioactive material in a space station in orbit.
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The 155mm W48 nukes were real nukes, but very inefficient. One 155mm nuclear shell weighed 54kg and had a yield of 0.072 kilotons of TNT. A 16" nuclear shell weighed about 20x as much but had a 200x greater yield (15-20 kilotons of tnt)
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Maybe I have a biased view of world events, but it feels like there's less respect for joint agreement in the world and less respect for regulation, or allowing regulation the ability to function as designed, at least in the U.S. (and it seems like the world is heading a similar direction).
Lessening an absolutist stance on this in favor of a more nuanced regulatory policy that requires more in depth checking seems to me like something we'll regret later when we find the agency is toothless, either because it always was in regards to this or because it was slowly defanged without people noticing.
Lessening an absolutist stance on this in favor of a more nuanced regulatory policy that requires more in depth checking seems to me like something we'll regret later when we find the agency is toothless, either because it always was in regards to this or because it was slowly defanged without people noticing.
The other fact to remember about fission explosives is that smaller == dirtier. The tiny W54 got a 1 kiloton yield from 5kg of plutonium. The contemporary Mark 18 Nuclear Bomb got 500 kilotons out of 60kg of uranium. 12 times the fissile material gave 500 times the explosive yield. Less energy converted into heat means more energy left in the form of radioactive material. Much of said radioactive material is going to end up deposited on the inside of your engine.
155mm was the diameter. According to Wikipedia they were 34 inches long. So quite a bit bigger than a 10cm sphere, which is what was implied in the question.
Makes sense, thanks.
It was thought of
https://en.m.wikipedia.org/wiki/Project_Orion_(nuclear_propu...
Now I don't know how feasible is making a nuke as small as you suggest.
Now I don't know how feasible is making a nuke as small as you suggest.
Thanks, now i remember hearing about this.
> Project Daedalus later proposed fusion explosives (deuterium or tritium pellets) detonated by electron beam inertial confinement. This is the same principle behind inertial confinement fusion. Theoretically, it could be scaled down to far smaller explosions, and require small shock absorbers.
That's an interesting tidbit about the size. Also reminds me of the Deadalus spaceship from the stargate universe.
But it sounds like politics is the only limit here, surely they can ammend the treaty to allow space-travel work under IAEA supervision.
> Project Daedalus later proposed fusion explosives (deuterium or tritium pellets) detonated by electron beam inertial confinement. This is the same principle behind inertial confinement fusion. Theoretically, it could be scaled down to far smaller explosions, and require small shock absorbers.
That's an interesting tidbit about the size. Also reminds me of the Deadalus spaceship from the stargate universe.
But it sounds like politics is the only limit here, surely they can ammend the treaty to allow space-travel work under IAEA supervision.
Welp, why make a small one then? Just make a big one :-)
Sibling comment is a good summary of most of the issues. I would add that you would lose quite a bit in payload mass to the additional shielding you would need so as to not fry your electronics/kill your crew. This would be in addition to what you would already be carrying to protect against existing ionising radiation from solar flares and alike.
Your last point about having to do radiation shielding anyways is interesring. I wonder if there are now materials or designs that can address this since it was firsr researched in the 70s and 80s.
The critical mass of a bare sphere of plutonium-239 (the isotope usually used to make bombs) is about 10 kg. Some percent can be shaved off this with a neutron reflector around the core and other design tricks. The American W54 warhead of the 1950s was 23 kg and the core was probably around one-third of the entire mass of the bomb. That is likely the practical limit for traditional designs.
As for what might be feasible within the laws of physics, rather than current engineering, I'm not sure there's a clear answer. Increasing the density of the fissile matter reduces its critical mass, which is why they implode the core with conventional explosives in most designs. There are other ways of compressing matter to very high densities. For example, subjecting it to hot enough plasma, like in a magnetic confinement fusion reactor, might work. But stuff like that is science fiction and will be for a long time.
As for what might be feasible within the laws of physics, rather than current engineering, I'm not sure there's a clear answer. Increasing the density of the fissile matter reduces its critical mass, which is why they implode the core with conventional explosives in most designs. There are other ways of compressing matter to very high densities. For example, subjecting it to hot enough plasma, like in a magnetic confinement fusion reactor, might work. But stuff like that is science fiction and will be for a long time.
W48 is the best we could do in 1963, that was 59 years ago. I’m sure if they did build a better one we wouldn’t hear about it. For example Suitcase nukes are probably a real thing, or at least something like the soda machine from Sun of All Fears.
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I was just thinking more about this but wouldn’t a rotational detonation engine impart torque and so spin up a space craft?
https://www.youtube.com/watch?v=fRMMSyCcTDI
I live vicariously through channels like Integza and Tom Stanton. I've wanted to do some of this stuff for over 20 years, specifically electrohydrodynamic (EHD) engines, but spent nearly the entirety of the last 2 decades merely surviving. It's a strange feeling to watch the world make basically no progress over many years, then suddenly go through an inflection point where suddenly everything is solved and there's no way to catch up. Like with flying cars, reusable rockets, AI..
I dunno, I just feel really inspired, but am also mourning the passing of my own life and all that wasted potential. These are all great inventions, super simple, easy to build, but why the heck were we forced to do everything the hard way for so long and still not make rent? These individual projects are really cool, but I worry that we aren't solving the fundamental problem of underemployment that forces fish to ride bicycles instead of swimming freely. Still just a rat in a cage and all that.