Earth is 12700 km in diameter, so such an image would be 688 pixels across.
Basically you won't be reading license plates but you'd see enough to identify evidence of very large scale construction, and with multiple images over time I bet you could draw even more conclusions.
This requires sending something to at least about 548 AU and then effect falls off from there but anything you send that far will be going at a velocity that would keep it going. You would be in effective range for some time but basically you'd need to keep sending satellites to that distance in order to keep using the technique. You'd also want to send them into different directions in order to image different parts of the sky.
It’s basically imaging one exoplanet per satellite. Would be good to figure out a way to slow down at 500 AU. In order to maximize the time for observation.
I wonder about all the extraterrestrial AI swarms that have already imaged earth.
Surely it has happened. They must have all spotted our planet millions of years ago and must be watching us with a continuous high-resolution feed. They've seen our dinosaurs. Their interest will really be piqued when they finally see us invent electricity, though that might be some time in the future for them.
Perhaps even gravitational lensing is primitive to them. Perhaps they're able to break and manipulate physics and peer directly into our light cone, breaking the speed of light. Perhaps through direct wormholes they're already here - computronium in the very oxygen atoms that surround us. In rock silicates, in the air you breathe, in your hemes, in your brain. Calculating.
But perhaps we're the only intelligent species in the entire universe. That is also a possibility. Some big names in astrophysics, such as David Kipping, suggest strongly that we should not rule out that hypothesis. I find his suggestions haunting and beautiful at the same time. You need to watch his videos, and this is a good start: https://www.youtube.com/watch?v=PqEmYU8Y_rI
And finally, it may be that we're all just a historical simulation. Or maybe that's ascribing too much importance to ourselves. Maybe we're just a slop simulation on some AI's plaything, existing for no reason at all. Background NPCs with self-importance, ephemeral existences. But procedural generation at scale isn't really all too different from the laws of the physical universe itself.
The scale of the universe fills me with awe. Every time I think about it, my worries about random algo-rage and clickbait fades away to nothing. It deeply contextualizes our short time here.
This comment encapsulates how poorly we humans are at accepting unknowns. For me, that explains a lot of our belief systems. The fact we can’t just take the unknown but instead have to fill in the blanks with what ifs. and create a narrative like we know anything about the unknown thing. It helps us feel like we understand it more. That’s literally how religions and a lot of other things get created, it’s a pattern, then the logical person sees the patterns and say it’s a simulation. A quite predictable filling of another blank.
As Lynn Margulis reminded us we are not the main show. Our individual intelligence is highly over rated. The brain itself is kludge upon kludge accumulating over thousands of years, to solve problems that keep changing with time and environmental changes. Its quite a piece of crap actually if you tabulate all the accumulated junk. We arent as interesting as we think we are.
Some of the tech and knowledge generated might be interesting. But compare it with to photosynthesis or butterfly metamorphosis or the fact that microbes can double their population in a few hours, all of which is happening without needing any human intelligence. So they may very well be watching but are more curious about a rose or a redwood tree than all the random and superficial activity the chimp brain produces.
Artifical solar capture systems exist. Synthetic biology also bridges that gap as well and the genetic basis is known and has been manipulated. Granted, coming up with more efficient photosynthesis is very hard, but I don't share your "we humans are stupid" opinion here at all whatsoever.
> or butterfly metamorphosis
Nothing fascinating here. It is just a genetic program. Viruses have similar programs too - yes, no metamorphosis, but take retroviruses and the syncytium. Mammals only reproduce thanks to retroviruses (not 100% correct, but look at this here: https://www.pnas.org/doi/10.1073/pnas.0707873105)
> or the fact that microbes can double their population in a few hours
Wow, we humans surely do not have cells that double. Oh wait ... nevermind. Humans consist of cells. Who would have thought...
Yes, microbes are much faster, but they don't have to coordinate as much as humans do in 3D, not even in a bacterial biofilm. And we have to double a lot more DNA than bacteria do, so of course they are faster.
> about a rose or a redwood tree than all the random and superficial activity the chimp brain produces
That comparison is weird. A rose is thinking as much as a chimp brain?
The human brain is special. Chimps are very clever too but humans have very solid abstract thinking. Animals have this too, to some extent (predator hunting prey, chimps have hunting strategies) but e. g. look at mathematics - animals don't waste their time coming up with higher order theorems.
>But perhaps we're the only intelligent species in the entire universe. That is also a possibility. Some big names in astrophysics, such as David Kipping, suggest strongly that we should not rule out that hypothesis
They may be planted by alien AI to lull us into false sense of security.
An even more ridiculous dream of mine: I hope that aliens build a similarly amazing telescope, point it at Earth, and share the images with us, so that we can _see_ our Earth in the distant past.
According to AI, an equivalent would be roughly when Google maps shows you 10mi/20km reference scale.
Turning off the labels, aliens would probably assume that the world is naturally full of green stuff that is dealing with some strange grey infestation.
> aliens would probably assume that the world is naturally full of green stuff that is dealing with some strange grey infestation.
I think they would draw the correct conclusion, actually. I know it's popular to compare humans to mold or cancer or whatever these days, but this kind of thing is both unrealistic and insulting to the aliens, who by the definition of the scenario are at least as smart as we are, quite probably more.
A kilometer scale telescope contract would exercise all the right pipelines for massive orbital buildout like in-situ assembly, multi-lift cadences, and big-old infra. And it'd look cool as hell in the night sky during assembly.
There is no "building" such a thing. All we could do right now is send the "telescope probe" >500AU away, on the opposite side of the sun from the observation target, then hope it still works 80 years later or so when it gets there.
Edit: My point is that you can't "build" such a thing and later point it somewhere-- you have to fly the camera part of the "telescope" about 3 times as far as voyager 1 went, exactly opposite of your observation target, and it is not gonna stay there for too long either.
As long as we improve rapidly at both drone-building and exoplanet target selection, it is not really gonna be worthwhile because both the drone hardware and the target will be hopelessly obsolete before we even get halfway to the observation point.
Well, there is a way to do it slowly, the probe(s) just need to be in a 500AU circular orbit. At that distance power and thrust are an issue, and RTGs seem like a better choice than solar. Certainly, takes longer to get to orbit than fly through a point for a pic, but you would get a lot more pics.
First: Orbital period out there is over 10000 years.
And if you circularize (which is expensive to do in delta-v), you minimize the time window you have for observation (because you're basically pointing your speed vector straight to outside of your observation cone).
The orbital velocity at this distance is around 1 km/s, so you can fairly trivially (compared to anything else) zero it out. Then you can just hover in place, the solar gravity acceleration at this range is in _microns_ per second squared.
For all intents and purposes, you'll be in the interstellar space.
In order to get something there fast enough it would be traveling out very fast. Getting something there to orbit I think is not realistic for us any time soon.
> so it's not too different to "get there" and "orbit there".
But to "get there" within any reasonable timespan requires going really fast - which is currently highly impractical. And then once you get there, you have to them cancel pretty much all of that velocity which is not just a "few percent more delta V".
The wild thing is that, if I understand it correctly, if you were floating in a spacesuit at the same spot you'd also see that resolution (likely highly distorted) with the naked eye.
Close enough that we could probably develop a probe to get there in the next few centuries and check it out. What are the current popular candidates for propulsion systems capable of accelerating to near the speed of light?
Just going to recycle this comment I made in reply to an almost identical comment as yours. I don't think you folks realize how big space actually is.
The speed of light is 1079 252 848 km/h, the fastest space craft ever made was the Parker Solar probe (using a sling shot) clocking in at 692 000 km/h. So at that speed it would take, 1559 years to travel one light year.
This planet sits at a distance of 48 light years, so it would 74 832 years to get there. Just for good measure, when it gets there it would also take 48 years for us to know that since radio travels at the speed of light.
Note, that the speed of the spacecraft I mentioned was the peak speed. Space is big, really big.
Science fiction has entertained and inspired millions of people and we should all be grateful for that but it has also distorted what people think space really is.
When you consider the scale of space it becomes pretty understandable why the Milky Way isn't teeming with civilizations sending large amounts of mass all over the galaxy. A realization one comes to despite the facts that it has taken humans a blink of an eye (on a galactic timescale) to go from tools to rockets and the Milky way is billions of years older than the entire history of the Earth.
Probably more likely that we work out how to fold spacetime than we get there in anything like a high enough percentage of the speed of light - the fastest object we ever made travelled at something like ~0.064% * C so we are looking at ~750 years with current technology and presumably we'd need to switch on the probe in 3/4 of a millennium and figure out how to slow it down and get it into some sort of orbit around the planet.
750 years is hard for me to get excited about even as a vampire.
It’s highly unlikely we’re ever getting FTL. We should become comfortable with that and let go our fantasies. Let theoretical physicists chug away at this, we should get underway with projects that are possible with known science.
Depends on who you mean as "we". The speed of light isn't a speed limit. If you can create a ship that is capable of 1g acceleration, it doesn't just stop accelerating as it reaches the speed of light relative to some stationary object, like Earth. Instead you start getting relativistic effects and things start getting very weird with time and distance doing some funky stuff. You keep zooming along just fine from your perspective, but an at-rest observer on Earth would see your ship asymptotically approach the speed of light, but never exceed it. The universe is very weird. In any case you could viably travel billions of light years in a single human lifetime, but for an observer at rest billions of their years would genuinely pass. In other words, traveling into the future is very much a real thing, so far as our current understanding of the universe goes.
The search term on this is 'relativistic starship.' Here's [1] a calculator to see what the math works out to for a ship capable of accelerating at 1g indefinitely. So for instance you could travel to Andromeda, some 2 million light years away, in about 28 years. But 2 million years would really pass for those at relative rest, such as those on Earth. So if you came back, the humanity you found (if any) would be unimaginably different.
And this isn't some just some weird fringe theoretical/mathematical thing. For instance GPS satellites have to compensate for time dilation because relativistic effects would otherwise have a substantial effect. Another example is at things like the large hadron collider. As a convenient effect of relativistic effects, emergent unstable particles exist far longer than they 'normally' would before decaying due to the fact they're moving at relativistic rates.
Relativistic starships are impossible because they require impossible amounts of fuel. "If you can create a ship that is capable of 1g acceleration" is doing a lot of heavy lifting. The rocket equation means you need to take along exponentially increasing amounts of fuel
Even antimatter rockets top out at 50% of light speed. Laser boost like with Dyson Swarm could get similar speeds because time dilation slows down the acceleration.
This isn’t gonna work, space isn’t truly empty. Even with antimatter propulsion the interstellar medium will start to vaporize your ship at speed above 0.2c.
Even if FTL is achievable (which I agree, highly unlikely), it's still extraordinarily slow on cosmic scales. The closest star is a little over 4 ly away!
And probing the universe outside the Milky Way? Forget about it.
1. if FTL is achievable, then presumably it isn't limited to 1.00000000001 x C
2. I like to think about the size of the universe by always remembering that with the naked eye, on a good night, there's only a single object in the entire night sky that isn't in our galaxy (M3, the Andromeda Galaxy).
The entire universe seems to be inside a giant black hole, anyway, and the more it goes, the more evidence is found to support that. Might as well find a black hole and visit other universes than explore our own.
It would help if our science wasn’t distracted by things like global warming and nazi governments though. There are definitely ways we can help the process * right now *
Scientists and engineers with an interest in such things would have an easier time working on it, if the broader economic and civic context they work in wasn't being messed with by demagogues.
They shouldn't be drafted to resolve the rise of petty tyrants. It's a waste of their time.
With variations on nuclear propulsion we could plausibly get to up to around 12% the speed of light. At least that's the number quoted for Project Daedalus [1], which is using nuclear fusion for the first stage and nuclear-powered ion engines for the second stage. With the cruder but more realistically achievable right now Project Orion design (riding the shockwaves of nuclear bombs) you could still get to ~3% the speed of light
But even at 0.12c, we are looking at 400 years to get there. And we'd be zooming by at 12% the speed of light. If we want to slow down a bit that'd add hundreds of billions to the cost.
It might be worth waiting another century to see if we can come up with a faster design in that time. Not like closer targets like Alpha Centauri, where the thing stopping us is mostly just the absurd cost
> But even at 0.12c, we are looking at 400 years to get there. And we'd be zooming by at 12% the speed of light. If we want to slow down a bit that'd add hundreds of billions to the cost.
That’s the really hard part. If it’s almost science fiction to accelerate to 0.12c, it’s certainly much more difficult to slow down. At that speed we’d travel and pass this small system in mere minutes.
You just turn around halfway and use your main drive to decelerate. Yes, that does double the travel time, but it's the only way to do it. The hard part is then finding ways to get to a faster speed at turnaround time.
In most realistic settings it's even easier. For example a Project Daedalus probe only accelerates for four years before running out of fuel. So you could decelerate in just four years. Maybe a bit more, since you only have the smaller second stage engines. But essentially you are accelerating for four years, coasting for 392 years and decelerating for another four years. Accelerating for the whole time and turning around in the middle would be faster, but we don't have the fuel for that
The issue is that in the original architecture without breaking you burn 50k tonnes of fuel to get 1k tonnes of payload up to 12% lightspeed. If you want to break all the way back to zero, you need to 50k tonnes of fuel to break. But that means you need to accelerate another 50k tonnes of fuel up to speed.
Which means you need 50 times for fuel to get from 0.11c to 0.12c, and you need to accelerate that fuel to 0.11c, so you need more than 50 times the fuel for the step from 0.10c to 0.11c, and an even larger factor more to accelerate from 0.09c to 0.10c, etc. So you don't just require another 50*50k = 2M tonnes of fuel, but an exponentially larger amount. The tyranny of the rocket equation
I think the only way political will can fund nasa to realize these 1960 design ideas is an infinite capacity arch rival that threatens/render irrelavent either the dollar's supremacy or american power (and just those two, because apparently these days there is no "threat"/need to defend a higher cause, like the neo-liberal rules based system or democratic or human right values). Also that arch-rival that is probably/likely not china(practically speaking)
Those 190km/s of the Parker solar probe were, crucially, periapsis speed.
This is a bit like bouncing a rubber ball from a building, measuring its speed at ground level and then going: "Given our fastest achieved speed, we expect to hit the cloud level in <10s".
~200km/s sustained speed is already insanely optimistic for anything we could realistically build in the next half century, so your position is even more ironclad than it looks at first glance.
Yep. We haven't really figured out how to do a good government that lasts more than 200 years. Maybe unless you think monarchy is good, in which case I still don't want to share a spaceship with you.
I have no doubt that even the most republican of cultures launched from Earth would end up thoroughly monarchistic by the time the generation ships arrived at their destination. At best monarchistic - who knows what savage new forms of society could evolve in that sort of context?
There is a lot of precedent for this. Even on Earth, in 2026, international maritime law states that there is no such thing as a vessel with "democracy" and that a captain always has supreme command. Ships, airplanes, etc are all in a category that operate as strict autocracies.
> Perhaps, but it is horrifically long in terms of human stuff.
Not really, unless you're obsessed with the idea that great works need to happen within your lifetime. Europe is chock full of cathedrals that took 400-600 years to build, worked on by countless generations who would never live to see them completed.
The difference there being that at the end of your day, having spent it masoning, you could leave the cathedral and go back to your family and have a walk in the fields and drink and be merry with people loved and new. The project wasn't the entiriety of your existence, it was merely the means to pay for it.
Unless we have generational ships the size of small countries, I'm not sure the human brain - unaided and non-forcedly evolved to do so - would be able to handle essential incarceration in a series of metal tubes for its own and its descendents existences.
Generational ships would of course need to be very large, but I doubt it would need to be as large as you think. And it doesn't need to look like metal tubes. Many northern cities have extensive underground or between-building pedestrian bridges and large shopping malls, etc that can provide quite a lot of variety and the feeling of open and green spaces that is pretty attractive during long cold winters. Whether that's 'enough' to avoid mental health issues in a permanent setting is of course a different story, but that's just one of thousands of problems that would need to be solved before that ever comes close to reality :)
Yeah, this is the problem though - ironically highlighted by my still-maintained love and hope for Starship: Beyond Earth orbit, the energy requirement to move even small tens of tons of useful life-sustaining mass is incredibly expensive.
Like, to get a useful amount of people to Mars would be... the wealth of a first world nation for tens of years. Even using nuclear engines.
A generational megaship travelling at some small percentage of c to a nearby useful star (not even the nearest ones, which are all a bit shit)?
There's just nothing within our current projected reality that could even begin to accomodate that possibility.
Never mind the fact you'd need redunancy, and at least a few hundred years of testing to ensure that whatever mega project you could ultimately send wouldn't simply get vaporised halfway through, from realities unknown.
Maybe I'm over-thinking things. It seems like a lot of people's existences essentially revolve around a pocket-sized glowing rectangle.
Future AI and a database of all of humanity's experience before launch might be enough to keep the generational populace amused and distracted for the entiriety of their meagre, trapped existence... .
Back yard meaning we can see it but never touch it. If the ship to get there was ready today, it would get there in the year one-million? Back yard is Mars, Venus, moon. And I'm being generous with Mars and Venus.
Yeah, if your username is any indication of your age, you've possibly taken much the same trajectory of pessimism that I have. As a youth, I assumed we'd be hitting multiple Cs or bending space time when I was an adult; As an adult I thought we might get a percentage of C and conquer the solar system; Now I realise Just How Much Effort it would be to accomplish much of any value on our own Moon, never mind Mars.
I still hold on to the idea that very long term we might make strides in our own solar system, but it is a depressingly-longer timescale than I always used to believe.
Unless we have some magic-level shift in our understanding of physics, we're never getting anything beyond Von Neumann probes to other stars, and even then we're talking thousands of years.
If we design a probe that travels at speed of light it would reach there in 48 years and it would send back what it's seen after another 48 years. It would take multiple generations of scientists to work on this project. The longest we have worked on, are Voyager projects. Can we expect that level of commitments from our governments or corporations? Voyager became successful because people could see distant futures. We can barely plan few years ahead.
If you could solve propulsion enough to accelerate and decelerate a spaceship at just 1G, you could forget the probe and just send people there. While it would take ~50 years of earth time, it would only take ~7.5 years for the astronauts. They could reach the planet with most of their lives free to go to work studying or even colonizing it.
This is indeed an interesting perspective, but "constant 1g rocket acceleration" is not even an engineering pipedream, it's strictly fantasy territory.
I had this realization in high school. At the time I did not appreciate how impossible it is to accelerate at 1G for that long. Absent some entirely new physics becoming available. All signs point to it not being possible, so not even likely new physics could exist.
This is where English’s defective subjunctive makes life harder: The point wasn’t about the practicality of the probe from a scientific position, but rather pointing out that even in a best-case scientific scenario, the political-economic-cultural forces are against us.
> Can we expect that level of commitments from our governments or corporations?
Clearly, right now we cannot. This is one of the worst obstacles to progress in these areas that I see, and I don't see any obvious way to fix it.
The situation we're currently in would've been utterly unfathomable to me 30 years ago. I have lost a great deal of the hope and optimism I held in the past. Interstellar exploration is but one of many fields where we are suffering due to short term thinking.
why, so they can watch corporate news from earth to get depressed? /s
Actually, it's a great question. Even if we have single photon sensitivity detectors, just what kind of power would a laser need? Or would it be some other area of the emf spectrum? Or some other kind of communication? Sci fi ventures into gravitational waves sometimes
Small fusion reactors don't really solve any of the key challenges. You need reaction mass to accelerate, you run out of reaction mass way too quickly even with a magical energy source on board to throw it out the back of the ship really fast.
laser propelled solar sails are the only plausible solution at the moment and it is not a given that even that is possible. Lots of engineering challenges there that may not have solutions.
other ideas:
1. be way more patient
2. anti matter based propulsion (more out there than solar sails)
3. nuclear bomb based propulsion
One issue is as you get to these speed little bits of dust will anhillate the probe, so you need some kind of shielding, raising the mass budget, making it all the harder. A solar sail has to be able to survive holes getting poked it in it and still working, etc.
Interstellar travel is probably not ever going to happen. Even if we have antimatter propulsion (which is still probably not practical even under ideal circumstances), we’re still talking hundreds of years of travel time to get to somewhere like this star.
This also goes for aliens visiting Earth. Interstellar travel is just so impractical that I don’t think anyone has come on safari to Earth.
A generation ship is probably doable with some level of conceivable technology. We just have to figure out how to be self sufficient out there then we have all the time in the world, or universe. That's a big "just", I know.
One of the Voyager probes measured the density of the interstellar vacuum at 80,000 protons (and the same number of electrons) per cubic meter. A proton going through a piece of aluminum foil delivers a roughly constant amount of energy regardless of speed; a relativistic proton will pinch through and carry most of its energy with it.
(No punchline; I just think that's cool. I understand that the real problem is the rare dust grain, not the ubiquitous gas.)
The political challenge of funding a laser program just for research for centuries seems just as daunting - lacking the capability for some self repairing, self healing devices, the automated or (lobster-ai) probe going to stars is just as far away as when Charles Stross first wrote about it in Accelerando some twenty years ago. Given the collapse of political norms, looking back, the decades long research projects of the US space program appear to be soon relics of the past.
I wouldn't bet on and as I understand theory allows a shorter routes. Major caveat is weve never observed them and their existence doesn't guarantee they're traversible.
What's exciting to me is that the existence of such a planet provides fuel for more research into the field.
I'm always so alienated (sorry) by the excitement around things like this. People start fantasizing about FTL and space arks and there is just no evidence that any of that is possible, desirable, effective, anything really.
I know I'm a killjoy, but I do think there's something negative about the impact of science fiction on engineers. Like, the people who tend (no offense) to be the most literal, black and white thinkers get exposed to art and instead of processing it as the output of human creativity, they start to imagine that it's desirable or even real.
> Like, the people who tend (no offense) to be the most literal, black and white thinkers get exposed to art and instead of processing it as the output of human creativity, they start to imagine that it's desirable or even real.
Why can't you process their fantasizing about it as an output of human creativity?
I don't think I've ever sounded so cynical in my life, but something about the way sci-fi fandom bleeds into real science really makes me deeply uncomfortable.
cynicism and critique are comfortable positions imo. i appreciate the relatively newfound cultural shift back towards earnestness (although i can already feel the pendulum starting to swing back)
There is too much fantasy about distant habitable planet and not enough about making a planet in solar system habitable or building artificial habitats
The speed of light is 1079 252 848 km/h, the fastest space craft ever made was the Parker Solar probe (using a sling shot) clocking in at 692 000 km/h. So at that speed it would take, 1559 years to travel one light year.
This planet sits at a distance of 48 light years, so it would 74 832 years to get there. Just for good measure, when it gets there it would also take 48 years for us to know that since radio travels at the speed of light.
Note, that the speed of the spacecraft I mentioned was the peak speed. Space is big, really big.
They detected helium escaping from the upper atmosphere which they believe to be evidence of a retained atmosphere, but haven't been able to fully identify the elements present in the lower atmosphere.
Due to the density of the planet they believe it could be a water world, or a mostly-icy world due to the lack of hydrogen found, and the lower atmosphere could consist of nitrogen, water vapor, and carbon dioxide. Since the host star is very inactive, there's little atmospheric erosion that would strip away a heavier atmosphere.
No, they detected helium, which would be in the upper reaches of the planet's atmosphere (as on Earth); they believe there are other gasses lower down, but the helium is what's confirmed.
We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far. The sciences, each straining in its own direction, have hitherto harmed us little; but some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the light into the peace and safety of a new dark age.
This whole search for life outside planet Earth is ... stupid.
Life is already on this planet. Why would it matter whether
life exists outside of this planet or not? I mean, this is
pointless. I understand that some have a financial motife
to drive this narrative, but it is not logical. The counter
argument is quite simple: IF there is no divine being, then
ALL of life's complexity is logical and natural. So, it really
does not matter WHERE it originates nor how many times. Why
would it matter if it originated 10000x or only once? Now,
I do not doubt that it has originated several times rather
than once, but my point is that this extra-terrestrial
search MAKES ABSOLUTELY NO SENSE AT ALL. That is not to say
that research and exploration in space are pointless, but
that it IS pointless to "search" for extraterrestrial life.
Yet none in the media point that out. It's all as if it were
some magical, mythical quest here.
Super-Earths are interesting but not technically habitable, at least not by humanoids, the gravity would be insane
There are new telescopes and techniques coming online really soon that can potentially find closer to Earth-sized planets but they probably won't be within 50 light years
adding: hmm maybe gravity not too horrible on 1140b but still INTENSE
I was skeptical about that as well so I googled it and:
>Helium cannot support life because it is a chemically inert noble gas. It does not form the complex, stable molecular structures (like carbon chains) required for biology. Unlike oxygen, it cannot be used by living organisms for cellular respiration to generate energy, making it an asphyxiant.
However, maybe we are projecting our current understanding of biology and shouldn't rule it out. I'm not a scientist so I have no idea.
Note: terrestrial chemistry is no different from chemistry that can occur anywhere, given the right molecules and conditions, and even then it’s a matter of degree.
Nitrogen being replaced by helium would actually be fine but for the niggling issue that we need nitrates. There are no heliates (?) to compensate. The name doesn’t even make sense… helium is the sole gas to have an ium end like metals- chemically it’s that meaningless what you call it as an ion…it shines elsewhere though.
For biology, it’s a necessary condition that the environment react with it and it reacts to the environment. Over time the two become deeply intertwined through the process of evolution.
It’s hard to see how that kind of evolution will occur if a lot of the environment is nonreactive.
Survival may be plausible though. There’s been some research showing some bacteria can survive in high helium environments. That’s a far cry from proving something like a bacterium can evolve in a helium environment that’s non-reactive though.
Why would it be necessary for life to depend on breathing atmosphere? The atmosphere could just help in keeping the temperature even and provide some nice pressure, maybe that’s favorable over vacuum.
Well, some years ago helium was a preferred way for suicide. This reflected very bad on the producers of party balloon helium tanks, so they added an amount of oxygen and it was no longer an effective way.
So the question becomes: How much of that atmosphere is helium?
Hmm, really? That's interesting.... [time passes] ... I found more information than I really needed on how to kill one's self with helium, and I saw some places making suggestions that helium be cut with oxygen, seemingly starting with a New Zealand coroner in 2011, but nothing suggesting this had been implemented at any sort of scale. The links I found on Amazon for party balloon helium tanks all mostly proudly state they are 99%+ helium.
Life needs energy to be moving around, without energy exchanges, by very definition, nothing interesting happens.
An inert element, for that reason is just not suitable for life. It's not a reasoning based on anthropocentricity it's just basic chemistry and mathematics. If things can't assemble together, and combine, and form more complex structures, you can't get life.
If you could get life out of simple basic atoms, we would see life everywhere, and we would be creating it everyday in labs. We don't.
Doesnt mean life can't exist there by using other elements, but detecting helium is not increasing the likelihood of finding life there at the very least.
Didn't know a rocky planet in the habitable zone of a red dwarf could retain atmosphere against intense stellar stripping.
Red dwarfs are known to be cooler (the habitable zone is therefore closer) and unstable.
I don't think LHS 1140b is "Earth-like" at all. Rather, it's more like a mini-Neptune, being boiled off by its star.
Edit: JWST emission spectroscopy of LHS 1140b as it passes behind its star rules out a mini-Neptune. https://arxiv.org/abs/2406.15136
We should build a solar lens telescope. By the time we're ready to use it, we'll have a bunch of candidates to point it at.
https://en.wikipedia.org/wiki/TOLIMAN
https://toliman.space/
They’re building one for stars within 10 parsecs of the sun ( and more specifically for Alpha Centauri) which should launch in the next year
There's a project that's going well from NASA for this. Still a moonshot but they've progressed through the early stages well so far.
https://www.nasa.gov/general/direct-multipixel-imaging-and-s...
What would a 25km resolution of earth look like
This is the Earth last Wednesday at 0.25º resolution (roughly 28 km per pixel at the equator): https://neo.gsfc.nasa.gov/servlet/RenderData?si=2050444&cs=r...
It's dead.
What a shame. I had expected the Earth to last a bit longer.
Earth is 12700 km in diameter, so such an image would be 688 pixels across.
Basically you won't be reading license plates but you'd see enough to identify evidence of very large scale construction, and with multiple images over time I bet you could draw even more conclusions.
We could make a license plate big enough that aliens could see it and know we are sophisticated.
Nah, let's just put a big sign "Kilroy was here", so they don't bother with the "mostly harmless" planet.
Enough to see cities
Great in depth youtube video on this project: https://www.youtube.com/watch?v=go-50Dpzs20
This requires sending something to at least about 548 AU and then effect falls off from there but anything you send that far will be going at a velocity that would keep it going. You would be in effective range for some time but basically you'd need to keep sending satellites to that distance in order to keep using the technique. You'd also want to send them into different directions in order to image different parts of the sky.
It’s basically imaging one exoplanet per satellite. Would be good to figure out a way to slow down at 500 AU. In order to maximize the time for observation.
Wow. 25km resolution of the exoplanet's surface.
Of course, getting the telescope into place, steering it, etc. - that's the hard part.
I wonder about all the extraterrestrial AI swarms that have already imaged earth.
Surely it has happened. They must have all spotted our planet millions of years ago and must be watching us with a continuous high-resolution feed. They've seen our dinosaurs. Their interest will really be piqued when they finally see us invent electricity, though that might be some time in the future for them.
Perhaps even gravitational lensing is primitive to them. Perhaps they're able to break and manipulate physics and peer directly into our light cone, breaking the speed of light. Perhaps through direct wormholes they're already here - computronium in the very oxygen atoms that surround us. In rock silicates, in the air you breathe, in your hemes, in your brain. Calculating.
But perhaps we're the only intelligent species in the entire universe. That is also a possibility. Some big names in astrophysics, such as David Kipping, suggest strongly that we should not rule out that hypothesis. I find his suggestions haunting and beautiful at the same time. You need to watch his videos, and this is a good start: https://www.youtube.com/watch?v=PqEmYU8Y_rI
And finally, it may be that we're all just a historical simulation. Or maybe that's ascribing too much importance to ourselves. Maybe we're just a slop simulation on some AI's plaything, existing for no reason at all. Background NPCs with self-importance, ephemeral existences. But procedural generation at scale isn't really all too different from the laws of the physical universe itself.
The scale of the universe fills me with awe. Every time I think about it, my worries about random algo-rage and clickbait fades away to nothing. It deeply contextualizes our short time here.
This comment encapsulates how poorly we humans are at accepting unknowns. For me, that explains a lot of our belief systems. The fact we can’t just take the unknown but instead have to fill in the blanks with what ifs. and create a narrative like we know anything about the unknown thing. It helps us feel like we understand it more. That’s literally how religions and a lot of other things get created, it’s a pattern, then the logical person sees the patterns and say it’s a simulation. A quite predictable filling of another blank.
> and create a narrative like we know anything about the unknown thing. It helps us feel like we understand it more.
In fairness, this very often helps us understand the unknown thing more.
It’s how science and discoveries are done too…
who made you the Pope of deciding what can and cannot be known?
That would be me.
Abdication syndrome.
As Lynn Margulis reminded us we are not the main show. Our individual intelligence is highly over rated. The brain itself is kludge upon kludge accumulating over thousands of years, to solve problems that keep changing with time and environmental changes. Its quite a piece of crap actually if you tabulate all the accumulated junk. We arent as interesting as we think we are. Some of the tech and knowledge generated might be interesting. But compare it with to photosynthesis or butterfly metamorphosis or the fact that microbes can double their population in a few hours, all of which is happening without needing any human intelligence. So they may very well be watching but are more curious about a rose or a redwood tree than all the random and superficial activity the chimp brain produces.
I'd be impressed if those microbes or butterflies visited the moon and came back to tell about it.
> But compare it with to photosynthesis
Artifical solar capture systems exist. Synthetic biology also bridges that gap as well and the genetic basis is known and has been manipulated. Granted, coming up with more efficient photosynthesis is very hard, but I don't share your "we humans are stupid" opinion here at all whatsoever.
> or butterfly metamorphosis
Nothing fascinating here. It is just a genetic program. Viruses have similar programs too - yes, no metamorphosis, but take retroviruses and the syncytium. Mammals only reproduce thanks to retroviruses (not 100% correct, but look at this here: https://www.pnas.org/doi/10.1073/pnas.0707873105)
> or the fact that microbes can double their population in a few hours
Wow, we humans surely do not have cells that double. Oh wait ... nevermind. Humans consist of cells. Who would have thought...
Yes, microbes are much faster, but they don't have to coordinate as much as humans do in 3D, not even in a bacterial biofilm. And we have to double a lot more DNA than bacteria do, so of course they are faster.
> about a rose or a redwood tree than all the random and superficial activity the chimp brain produces
That comparison is weird. A rose is thinking as much as a chimp brain?
The human brain is special. Chimps are very clever too but humans have very solid abstract thinking. Animals have this too, to some extent (predator hunting prey, chimps have hunting strategies) but e. g. look at mathematics - animals don't waste their time coming up with higher order theorems.
>But perhaps we're the only intelligent species in the entire universe. That is also a possibility. Some big names in astrophysics, such as David Kipping, suggest strongly that we should not rule out that hypothesis
They may be planted by alien AI to lull us into false sense of security.
If they let me watch the videos of our dinosaurs, I would happily let them use my hemes for their calculations.
https://www.youtube.com/watch?v=NQFqDKRAROI
An even more ridiculous dream of mine: I hope that aliens build a similarly amazing telescope, point it at Earth, and share the images with us, so that we can _see_ our Earth in the distant past.
> I hope that aliens build a similarly amazing telescope
I hope they did that eons ago so that I have a chance to see those images in my lifetime!
In theory we can then get 100 meter resolution on alien worlds. That would be insane.
According to AI, an equivalent would be roughly when Google maps shows you 10mi/20km reference scale.
Turning off the labels, aliens would probably assume that the world is naturally full of green stuff that is dealing with some strange grey infestation.
> aliens would probably assume that the world is naturally full of green stuff that is dealing with some strange grey infestation.
I think they would draw the correct conclusion, actually. I know it's popular to compare humans to mold or cancer or whatever these days, but this kind of thing is both unrealistic and insulting to the aliens, who by the definition of the scenario are at least as smart as we are, quite probably more.
Even on that scale, major roads and agricultural grids are clearly visible. The mark of abstract intelligence is unmistakeable.
This reminds of me canali : https://en.wikipedia.org/wiki/Martian_canals#Interpretation_...
Spectral analysis at that resolution would be much more telling.
On that scale, we really do look like mold.
A kilometer scale telescope contract would exercise all the right pipelines for massive orbital buildout like in-situ assembly, multi-lift cadences, and big-old infra. And it'd look cool as hell in the night sky during assembly.
There is no "building" such a thing. All we could do right now is send the "telescope probe" >500AU away, on the opposite side of the sun from the observation target, then hope it still works 80 years later or so when it gets there.
Edit: My point is that you can't "build" such a thing and later point it somewhere-- you have to fly the camera part of the "telescope" about 3 times as far as voyager 1 went, exactly opposite of your observation target, and it is not gonna stay there for too long either.
As long as we improve rapidly at both drone-building and exoplanet target selection, it is not really gonna be worthwhile because both the drone hardware and the target will be hopelessly obsolete before we even get halfway to the observation point.
Well, there is a way to do it slowly, the probe(s) just need to be in a 500AU circular orbit. At that distance power and thrust are an issue, and RTGs seem like a better choice than solar. Certainly, takes longer to get to orbit than fly through a point for a pic, but you would get a lot more pics.
First: Orbital period out there is over 10000 years.
And if you circularize (which is expensive to do in delta-v), you minimize the time window you have for observation (because you're basically pointing your speed vector straight to outside of your observation cone).
The orbital velocity at this distance is around 1 km/s, so you can fairly trivially (compared to anything else) zero it out. Then you can just hover in place, the solar gravity acceleration at this range is in _microns_ per second squared.
For all intents and purposes, you'll be in the interstellar space.
In order to get something there fast enough it would be traveling out very fast. Getting something there to orbit I think is not realistic for us any time soon.
I guess the point he's making is that the orbital velocity is pretty slow, so it's not too different to "get there" and "orbit there".
Of course, the rocket equation often makes "just add a few percent more delta V" pretty hard ;)
> so it's not too different to "get there" and "orbit there".
But to "get there" within any reasonable timespan requires going really fast - which is currently highly impractical. And then once you get there, you have to them cancel pretty much all of that velocity which is not just a "few percent more delta V".
an ort cloud of eye peices comes to mind
The wild thing is that, if I understand it correctly, if you were floating in a spacesuit at the same spot you'd also see that resolution (likely highly distorted) with the naked eye.
> if you were floating in a spacesuit at the same spot you'd also see that resolution (likely highly distorted) with the naked eye
…would you? The lensing would occur right at the apparent surface of the sun.
You would still need the sun shield in place obv.
48 light years is in our back yard.
Close enough that we could probably develop a probe to get there in the next few centuries and check it out. What are the current popular candidates for propulsion systems capable of accelerating to near the speed of light?
Just going to recycle this comment I made in reply to an almost identical comment as yours. I don't think you folks realize how big space actually is.
The speed of light is 1079 252 848 km/h, the fastest space craft ever made was the Parker Solar probe (using a sling shot) clocking in at 692 000 km/h. So at that speed it would take, 1559 years to travel one light year.
This planet sits at a distance of 48 light years, so it would 74 832 years to get there. Just for good measure, when it gets there it would also take 48 years for us to know that since radio travels at the speed of light.
Note, that the speed of the spacecraft I mentioned was the peak speed. Space is big, really big.
Science fiction has entertained and inspired millions of people and we should all be grateful for that but it has also distorted what people think space really is.
When you consider the scale of space it becomes pretty understandable why the Milky Way isn't teeming with civilizations sending large amounts of mass all over the galaxy. A realization one comes to despite the facts that it has taken humans a blink of an eye (on a galactic timescale) to go from tools to rockets and the Milky way is billions of years older than the entire history of the Earth.
Seriously even the nearest star is 6,200+ years at Parker probe speed.
Probably more likely that we work out how to fold spacetime than we get there in anything like a high enough percentage of the speed of light - the fastest object we ever made travelled at something like ~0.064% * C so we are looking at ~750 years with current technology and presumably we'd need to switch on the probe in 3/4 of a millennium and figure out how to slow it down and get it into some sort of orbit around the planet.
750 years is hard for me to get excited about even as a vampire.
It’s highly unlikely we’re ever getting FTL. We should become comfortable with that and let go our fantasies. Let theoretical physicists chug away at this, we should get underway with projects that are possible with known science.
Depends on who you mean as "we". The speed of light isn't a speed limit. If you can create a ship that is capable of 1g acceleration, it doesn't just stop accelerating as it reaches the speed of light relative to some stationary object, like Earth. Instead you start getting relativistic effects and things start getting very weird with time and distance doing some funky stuff. You keep zooming along just fine from your perspective, but an at-rest observer on Earth would see your ship asymptotically approach the speed of light, but never exceed it. The universe is very weird. In any case you could viably travel billions of light years in a single human lifetime, but for an observer at rest billions of their years would genuinely pass. In other words, traveling into the future is very much a real thing, so far as our current understanding of the universe goes.
The search term on this is 'relativistic starship.' Here's [1] a calculator to see what the math works out to for a ship capable of accelerating at 1g indefinitely. So for instance you could travel to Andromeda, some 2 million light years away, in about 28 years. But 2 million years would really pass for those at relative rest, such as those on Earth. So if you came back, the humanity you found (if any) would be unimaginably different.
And this isn't some just some weird fringe theoretical/mathematical thing. For instance GPS satellites have to compensate for time dilation because relativistic effects would otherwise have a substantial effect. Another example is at things like the large hadron collider. As a convenient effect of relativistic effects, emergent unstable particles exist far longer than they 'normally' would before decaying due to the fact they're moving at relativistic rates.
[1] - http://www.convertalot.com/relativistic_star_ship_calculator...
Relativistic starships are impossible because they require impossible amounts of fuel. "If you can create a ship that is capable of 1g acceleration" is doing a lot of heavy lifting. The rocket equation means you need to take along exponentially increasing amounts of fuel
Even antimatter rockets top out at 50% of light speed. Laser boost like with Dyson Swarm could get similar speeds because time dilation slows down the acceleration.
This isn’t gonna work, space isn’t truly empty. Even with antimatter propulsion the interstellar medium will start to vaporize your ship at speed above 0.2c.
We are still so slow and have had space travel for so little time, we are almost certainly on the "wait" side of the wait equation: https://en.wikipedia.org/wiki/The_Wait_Equation
Even if FTL is achievable (which I agree, highly unlikely), it's still extraordinarily slow on cosmic scales. The closest star is a little over 4 ly away!
And probing the universe outside the Milky Way? Forget about it.
1. if FTL is achievable, then presumably it isn't limited to 1.00000000001 x C
2. I like to think about the size of the universe by always remembering that with the naked eye, on a good night, there's only a single object in the entire night sky that isn't in our galaxy (M3, the Andromeda Galaxy).
The entire universe seems to be inside a giant black hole, anyway, and the more it goes, the more evidence is found to support that. Might as well find a black hole and visit other universes than explore our own.
What definition of black hole are you using?
It would help if our science wasn’t distracted by things like global warming and nazi governments though. There are definitely ways we can help the process * right now *
Good luck doing anything on any other planet if you can't even handle your own that's perfectly suited for your kind of life form.
Yeah, let's ignore current issues and instead focus on remote stars.
Scientists and engineers with an interest in such things would have an easier time working on it, if the broader economic and civic context they work in wasn't being messed with by demagogues.
They shouldn't be drafted to resolve the rise of petty tyrants. It's a waste of their time.
the message you replied to implied the exact opposite.
With variations on nuclear propulsion we could plausibly get to up to around 12% the speed of light. At least that's the number quoted for Project Daedalus [1], which is using nuclear fusion for the first stage and nuclear-powered ion engines for the second stage. With the cruder but more realistically achievable right now Project Orion design (riding the shockwaves of nuclear bombs) you could still get to ~3% the speed of light
But even at 0.12c, we are looking at 400 years to get there. And we'd be zooming by at 12% the speed of light. If we want to slow down a bit that'd add hundreds of billions to the cost.
It might be worth waiting another century to see if we can come up with a faster design in that time. Not like closer targets like Alpha Centauri, where the thing stopping us is mostly just the absurd cost
> But even at 0.12c, we are looking at 400 years to get there. And we'd be zooming by at 12% the speed of light. If we want to slow down a bit that'd add hundreds of billions to the cost.
That’s the really hard part. If it’s almost science fiction to accelerate to 0.12c, it’s certainly much more difficult to slow down. At that speed we’d travel and pass this small system in mere minutes.
You just turn around halfway and use your main drive to decelerate. Yes, that does double the travel time, but it's the only way to do it. The hard part is then finding ways to get to a faster speed at turnaround time.
In most realistic settings it's even easier. For example a Project Daedalus probe only accelerates for four years before running out of fuel. So you could decelerate in just four years. Maybe a bit more, since you only have the smaller second stage engines. But essentially you are accelerating for four years, coasting for 392 years and decelerating for another four years. Accelerating for the whole time and turning around in the middle would be faster, but we don't have the fuel for that
The issue is that in the original architecture without breaking you burn 50k tonnes of fuel to get 1k tonnes of payload up to 12% lightspeed. If you want to break all the way back to zero, you need to 50k tonnes of fuel to break. But that means you need to accelerate another 50k tonnes of fuel up to speed.
Which means you need 50 times for fuel to get from 0.11c to 0.12c, and you need to accelerate that fuel to 0.11c, so you need more than 50 times the fuel for the step from 0.10c to 0.11c, and an even larger factor more to accelerate from 0.09c to 0.10c, etc. So you don't just require another 50*50k = 2M tonnes of fuel, but an exponentially larger amount. The tyranny of the rocket equation
There is no drive, it’s all orbital slingshots with current technology. None of the other stuff people are talking about here exists…
I think the only way political will can fund nasa to realize these 1960 design ideas is an infinite capacity arch rival that threatens/render irrelavent either the dollar's supremacy or american power (and just those two, because apparently these days there is no "threat"/need to defend a higher cause, like the neo-liberal rules based system or democratic or human right values). Also that arch-rival that is probably/likely not china(practically speaking)
Adding to this:
Those 190km/s of the Parker solar probe were, crucially, periapsis speed.
This is a bit like bouncing a rubber ball from a building, measuring its speed at ground level and then going: "Given our fastest achieved speed, we expect to hit the cloud level in <10s".
~200km/s sustained speed is already insanely optimistic for anything we could realistically build in the next half century, so your position is even more ironclad than it looks at first glance.
Universe #23: keep solar systems far enough that they can't make war on each other.
We are looking at 75,000 years. You forgot the %.
Honestly a near millennia long expedition would be very cool, and doesn’t seem too long on the scale of space stuff.
Perhaps, but it is horrifically long in terms of human stuff.
Yep. We haven't really figured out how to do a good government that lasts more than 200 years. Maybe unless you think monarchy is good, in which case I still don't want to share a spaceship with you.
I have no doubt that even the most republican of cultures launched from Earth would end up thoroughly monarchistic by the time the generation ships arrived at their destination. At best monarchistic - who knows what savage new forms of society could evolve in that sort of context?
There is a lot of precedent for this. Even on Earth, in 2026, international maritime law states that there is no such thing as a vessel with "democracy" and that a captain always has supreme command. Ships, airplanes, etc are all in a category that operate as strict autocracies.
Sure.
How long's the longest voyage these days?
Mutinies aren't so common nowadays, but they were when ocean voyages were measured in months and years.
Tynwald, the Isle of Man's parliament, has operated continuously for over 1000 years
How's their space program coming along ;p pretty spacious place, ach!
> Perhaps, but it is horrifically long in terms of human stuff.
Not really, unless you're obsessed with the idea that great works need to happen within your lifetime. Europe is chock full of cathedrals that took 400-600 years to build, worked on by countless generations who would never live to see them completed.
The difference there being that at the end of your day, having spent it masoning, you could leave the cathedral and go back to your family and have a walk in the fields and drink and be merry with people loved and new. The project wasn't the entiriety of your existence, it was merely the means to pay for it.
Unless we have generational ships the size of small countries, I'm not sure the human brain - unaided and non-forcedly evolved to do so - would be able to handle essential incarceration in a series of metal tubes for its own and its descendents existences.
Generational ships would of course need to be very large, but I doubt it would need to be as large as you think. And it doesn't need to look like metal tubes. Many northern cities have extensive underground or between-building pedestrian bridges and large shopping malls, etc that can provide quite a lot of variety and the feeling of open and green spaces that is pretty attractive during long cold winters. Whether that's 'enough' to avoid mental health issues in a permanent setting is of course a different story, but that's just one of thousands of problems that would need to be solved before that ever comes close to reality :)
Yeah, this is the problem though - ironically highlighted by my still-maintained love and hope for Starship: Beyond Earth orbit, the energy requirement to move even small tens of tons of useful life-sustaining mass is incredibly expensive.
Like, to get a useful amount of people to Mars would be... the wealth of a first world nation for tens of years. Even using nuclear engines.
A generational megaship travelling at some small percentage of c to a nearby useful star (not even the nearest ones, which are all a bit shit)?
There's just nothing within our current projected reality that could even begin to accomodate that possibility.
Never mind the fact you'd need redunancy, and at least a few hundred years of testing to ensure that whatever mega project you could ultimately send wouldn't simply get vaporised halfway through, from realities unknown.
Knowing the variety of lives lived on earth as we speak, I'm fairly certain the first space born generation would adapt to it.
Provided the Earthlings that were sent along don't let their incarceration induced insanity infect the youngin's.
Maybe I'm over-thinking things. It seems like a lot of people's existences essentially revolve around a pocket-sized glowing rectangle.
Future AI and a database of all of humanity's experience before launch might be enough to keep the generational populace amused and distracted for the entiriety of their meagre, trapped existence... .
Back yard meaning we can see it but never touch it. If the ship to get there was ready today, it would get there in the year one-million? Back yard is Mars, Venus, moon. And I'm being generous with Mars and Venus.
Yeah, if your username is any indication of your age, you've possibly taken much the same trajectory of pessimism that I have. As a youth, I assumed we'd be hitting multiple Cs or bending space time when I was an adult; As an adult I thought we might get a percentage of C and conquer the solar system; Now I realise Just How Much Effort it would be to accomplish much of any value on our own Moon, never mind Mars.
I still hold on to the idea that very long term we might make strides in our own solar system, but it is a depressingly-longer timescale than I always used to believe.
Unless we have some magic-level shift in our understanding of physics, we're never getting anything beyond Von Neumann probes to other stars, and even then we're talking thousands of years.
> Yeah, if your username is any indication of your age
You might want to look up what the unix epoch is based on ;)
If we design a probe that travels at speed of light it would reach there in 48 years and it would send back what it's seen after another 48 years. It would take multiple generations of scientists to work on this project. The longest we have worked on, are Voyager projects. Can we expect that level of commitments from our governments or corporations? Voyager became successful because people could see distant futures. We can barely plan few years ahead.
If you could solve propulsion enough to accelerate and decelerate a spaceship at just 1G, you could forget the probe and just send people there. While it would take ~50 years of earth time, it would only take ~7.5 years for the astronauts. They could reach the planet with most of their lives free to go to work studying or even colonizing it.
This is indeed an interesting perspective, but "constant 1g rocket acceleration" is not even an engineering pipedream, it's strictly fantasy territory.
I had this realization in high school. At the time I did not appreciate how impossible it is to accelerate at 1G for that long. Absent some entirely new physics becoming available. All signs point to it not being possible, so not even likely new physics could exist.
We cannot design a probe that travels at the speed of light.
This is where English’s defective subjunctive makes life harder: The point wasn’t about the practicality of the probe from a scientific position, but rather pointing out that even in a best-case scientific scenario, the political-economic-cultural forces are against us.
> Can we expect that level of commitments from our governments or corporations?
Clearly, right now we cannot. This is one of the worst obstacles to progress in these areas that I see, and I don't see any obvious way to fix it.
The situation we're currently in would've been utterly unfathomable to me 30 years ago. I have lost a great deal of the hope and optimism I held in the past. Interstellar exploration is but one of many fields where we are suffering due to short term thinking.
Find a way to sell ads on it.
Short term thinking isn't why we are suffering. We are suffering because there are no promising avenues to pursue.
If you think of one, bring it up.
We have as much chance as a human stepping inside a bacteria (i.e. physics makes it near impossible)
This is so exciting.
why don't they check us out first?
Have you seen our track record of violence and general ignorance? I wouldn’t poke us with a ten light year pole.
Astrophage
Project Hail Mary :)
> in the next few centuries
assuming we can make it another few centuries, which seems increasingly unlikely.
need to get small fusion reactors online, then many options blossom.
And work out safe systems for hibernation, maybe rotate the crew in shifts
Oh yeah this is the stuff of science fiction coming to life
If we had a probe in orbit around this planet, do we have a way to stream data across 48 light years with any kind of reliability?
Send a lot of them and have them act as relays
why, so they can watch corporate news from earth to get depressed? /s
Actually, it's a great question. Even if we have single photon sensitivity detectors, just what kind of power would a laser need? Or would it be some other area of the emf spectrum? Or some other kind of communication? Sci fi ventures into gravitational waves sometimes
Small fusion reactors don't really solve any of the key challenges. You need reaction mass to accelerate, you run out of reaction mass way too quickly even with a magical energy source on board to throw it out the back of the ship really fast.
laser propelled solar sails are the only plausible solution at the moment and it is not a given that even that is possible. Lots of engineering challenges there that may not have solutions.
other ideas: 1. be way more patient 2. anti matter based propulsion (more out there than solar sails) 3. nuclear bomb based propulsion
One issue is as you get to these speed little bits of dust will anhillate the probe, so you need some kind of shielding, raising the mass budget, making it all the harder. A solar sail has to be able to survive holes getting poked it in it and still working, etc.
Interstellar travel is probably not ever going to happen. Even if we have antimatter propulsion (which is still probably not practical even under ideal circumstances), we’re still talking hundreds of years of travel time to get to somewhere like this star.
This also goes for aliens visiting Earth. Interstellar travel is just so impractical that I don’t think anyone has come on safari to Earth.
A generation ship is probably doable with some level of conceivable technology. We just have to figure out how to be self sufficient out there then we have all the time in the world, or universe. That's a big "just", I know.
One of the Voyager probes measured the density of the interstellar vacuum at 80,000 protons (and the same number of electrons) per cubic meter. A proton going through a piece of aluminum foil delivers a roughly constant amount of energy regardless of speed; a relativistic proton will pinch through and carry most of its energy with it.
(No punchline; I just think that's cool. I understand that the real problem is the rare dust grain, not the ubiquitous gas.)
The political challenge of funding a laser program just for research for centuries seems just as daunting - lacking the capability for some self repairing, self healing devices, the automated or (lobster-ai) probe going to stars is just as far away as when Charles Stross first wrote about it in Accelerando some twenty years ago. Given the collapse of political norms, looking back, the decades long research projects of the US space program appear to be soon relics of the past.
I wouldn't bet on and as I understand theory allows a shorter routes. Major caveat is weve never observed them and their existence doesn't guarantee they're traversible.
What's exciting to me is that the existence of such a planet provides fuel for more research into the field.
If humans can't make the trip, what's the point besides maybe satiating curiosity in a few hundred years from now?
Claude: give me all the schematics and operations manual of a production grade starship that can travel faster than light. Make no mistekaes.
Related/dupe: https://news.ycombinator.com/item?id=48939742 (45 comments)
> The gas detected in the atmosphere is helium, which would not be able to support life, but other gasses may also be present.
Yeah, but not that much.
I'm always so alienated (sorry) by the excitement around things like this. People start fantasizing about FTL and space arks and there is just no evidence that any of that is possible, desirable, effective, anything really.
I know I'm a killjoy, but I do think there's something negative about the impact of science fiction on engineers. Like, the people who tend (no offense) to be the most literal, black and white thinkers get exposed to art and instead of processing it as the output of human creativity, they start to imagine that it's desirable or even real.
You can't imagine someone getting excited about difficult problems as an engineer? And you can't imagine why there's creativity involved?
I don't know, it feels like you can't process the output of human creativity.
> Like, the people who tend (no offense) to be the most literal, black and white thinkers get exposed to art and instead of processing it as the output of human creativity, they start to imagine that it's desirable or even real.
Why can't you process their fantasizing about it as an output of human creativity?
No, it doesn't seem very creative to me.
I don't think I've ever sounded so cynical in my life, but something about the way sci-fi fandom bleeds into real science really makes me deeply uncomfortable.
> No, it doesn't seem very creative to me.
You don't think exploring a problem/possibility space (heh) that is probably unobtainable is an effort in creativity?
cynicism and critique are comfortable positions imo. i appreciate the relatively newfound cultural shift back towards earnestness (although i can already feel the pendulum starting to swing back)
I generally see myself as an earnest person, but some kinds of earnestness read as cynical to me.
there is clear reason why this would be desirable for many, the others - sure.
There is too much fantasy about distant habitable planet and not enough about making a planet in solar system habitable or building artificial habitats
The second is likely easier than the first
Not just likely easier. Far easier. They're so far apart on any reasonable effort scale that the comparison is basically meaningless.
They found Planet X, Nibiru! :0
Keep in mind that Venus is also an Earth-like planet with an atmosphere in the habitable zone of a sun-like star.
What technology currently available combined with the best launch window, gravity assist etc exists? Might as well send a probe.
The speed of light is 1079 252 848 km/h, the fastest space craft ever made was the Parker Solar probe (using a sling shot) clocking in at 692 000 km/h. So at that speed it would take, 1559 years to travel one light year.
This planet sits at a distance of 48 light years, so it would 74 832 years to get there. Just for good measure, when it gets there it would also take 48 years for us to know that since radio travels at the speed of light.
Note, that the speed of the spacecraft I mentioned was the peak speed. Space is big, really big.
500+ years, and it would likely need to be inert for most of that trip, space is big
Try 74 832 years actually.
let's send elon there.
> Researchers have found the first atmosphere surrounding an Earth-like, rocky planet orbiting within the habitable zone of a distant star.
Well, if they observed not only a planet orbiting the star but also the planet's atmosphere, it must not be a very "distant" star.
i do hope in my lifetime we find other animals on other planets
So that we still have animal to kill in our lifetime, after the ones on Earth are all extinct?
Am I understanding right? They detected an atmosphere but don’t know what it’s made of?
They detected helium escaping from the upper atmosphere which they believe to be evidence of a retained atmosphere, but haven't been able to fully identify the elements present in the lower atmosphere.
Due to the density of the planet they believe it could be a water world, or a mostly-icy world due to the lack of hydrogen found, and the lower atmosphere could consist of nitrogen, water vapor, and carbon dioxide. Since the host star is very inactive, there's little atmospheric erosion that would strip away a heavier atmosphere.
No, they detected helium, which would be in the upper reaches of the planet's atmosphere (as on Earth); they believe there are other gasses lower down, but the helium is what's confirmed.
Underlying paper from Science[0]
[0] https://www.science.org/content/article/astronomers-spot-fir...
How far will we peer into the unknown? What will we find out there?
We live on a placid island of ignorance in the midst of black seas of infinity, and it was not meant that we should voyage far. The sciences, each straining in its own direction, have hitherto harmed us little; but some day the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the light into the peace and safety of a new dark age.
aliems
This whole search for life outside planet Earth is ... stupid.
Life is already on this planet. Why would it matter whether life exists outside of this planet or not? I mean, this is pointless. I understand that some have a financial motife to drive this narrative, but it is not logical. The counter argument is quite simple: IF there is no divine being, then ALL of life's complexity is logical and natural. So, it really does not matter WHERE it originates nor how many times. Why would it matter if it originated 10000x or only once? Now, I do not doubt that it has originated several times rather than once, but my point is that this extra-terrestrial search MAKES ABSOLUTELY NO SENSE AT ALL. That is not to say that research and exploration in space are pointless, but that it IS pointless to "search" for extraterrestrial life. Yet none in the media point that out. It's all as if it were some magical, mythical quest here.
life generates intelligence , intelligence (may) generate traversable wormholes
we talked about this in great detail yesterday on HN with some fantastic comments
* https://news.ycombinator.com/item?id=48939742
NASA has a neat exoplanet catalog where you can also switch to its solar system view
* https://science.nasa.gov/exoplanet-catalog/lhs-1140-b/
Super-Earths are interesting but not technically habitable, at least not by humanoids, the gravity would be insane
There are new telescopes and techniques coming online really soon that can potentially find closer to Earth-sized planets but they probably won't be within 50 light years
adding: hmm maybe gravity not too horrible on 1140b but still INTENSE
(assuming Google's "AI" is correct)
> Gravity Formula: \frac{Mass}{Radius^2}\)Calculation: \(5.6 \div (1.73)^2 = 5.6 \div 2.9929 \approx 1.87\)
> if you weigh 150 lbs on Earth, you would weigh roughly 280.5 lbs on 1140b
> The gas detected in the atmosphere is helium, which would not be able to support life
Nonsense. You mean not able to support terrestrial life.
I was skeptical about that as well so I googled it and:
>Helium cannot support life because it is a chemically inert noble gas. It does not form the complex, stable molecular structures (like carbon chains) required for biology. Unlike oxygen, it cannot be used by living organisms for cellular respiration to generate energy, making it an asphyxiant.
However, maybe we are projecting our current understanding of biology and shouldn't rule it out. I'm not a scientist so I have no idea.
Note: terrestrial chemistry is no different from chemistry that can occur anywhere, given the right molecules and conditions, and even then it’s a matter of degree.
Nitrogen being replaced by helium would actually be fine but for the niggling issue that we need nitrates. There are no heliates (?) to compensate. The name doesn’t even make sense… helium is the sole gas to have an ium end like metals- chemically it’s that meaningless what you call it as an ion…it shines elsewhere though.
For biology, it’s a necessary condition that the environment react with it and it reacts to the environment. Over time the two become deeply intertwined through the process of evolution.
It’s hard to see how that kind of evolution will occur if a lot of the environment is nonreactive.
Survival may be plausible though. There’s been some research showing some bacteria can survive in high helium environments. That’s a far cry from proving something like a bacterium can evolve in a helium environment that’s non-reactive though.
Why would it be necessary for life to depend on breathing atmosphere? The atmosphere could just help in keeping the temperature even and provide some nice pressure, maybe that’s favorable over vacuum.
Well, some years ago helium was a preferred way for suicide. This reflected very bad on the producers of party balloon helium tanks, so they added an amount of oxygen and it was no longer an effective way.
So the question becomes: How much of that atmosphere is helium?
> helium was a preferred way for suicide
The era of ridiculous sounding last words came to an end
Hmm, really? That's interesting.... [time passes] ... I found more information than I really needed on how to kill one's self with helium, and I saw some places making suggestions that helium be cut with oxygen, seemingly starting with a New Zealand coroner in 2011, but nothing suggesting this had been implemented at any sort of scale. The links I found on Amazon for party balloon helium tanks all mostly proudly state they are 99%+ helium.
Would be briefly hilarious though as the squeaky response made it back through to mission control.
They didn't say oxygen is not present. 78% of earth's atmosphere is nitrogen and we are doing fine.
Helium is a noble gas. It forms no bonds and is unable to produce even a simple molecule, let along the complex ones needed for life.
Assuming non terrestrial life needs complex molecules. Which we can't know for sure.
Life needs energy to be moving around, without energy exchanges, by very definition, nothing interesting happens.
An inert element, for that reason is just not suitable for life. It's not a reasoning based on anthropocentricity it's just basic chemistry and mathematics. If things can't assemble together, and combine, and form more complex structures, you can't get life. If you could get life out of simple basic atoms, we would see life everywhere, and we would be creating it everyday in labs. We don't.
Doesnt mean life can't exist there by using other elements, but detecting helium is not increasing the likelihood of finding life there at the very least.
No, we really can know for sure.
Don't be so open-minded about extra-terrestrial life that your brain falls out.
Sure, but keep in mind that technically New Jersey is "habitable," so don't get too excited.
Florida is the typical and deserved target.
my Cleveland is extremely Brown right now: https://www.airnow.gov/state/?name=ohio
and blaming Canada.
They’re both the same basically now. Different weather, same assholes. Much of the FL natives I know had to flee to cheaper pastures.