It's just a funny little thing but I love how in a world of "megapixel" and even "gigapixel" space images we have here a "multipixel" imaging of planets, due to achieving a resolution of several pixels.
Though the 25km resolution mentioned actually sounds far, far better than the very pixellated planet in the "artist’s depiction". I suppose it depends how small and far away the planet is.
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.
Couldn't you do something like a Hohmann transfer orbit ? As I understand it, adjusting the orbits far out there isn't as demanding as one might think (you don't have to spend the same energy you took to get out there to get into an orbit. Of course, this also means you will not be able to stay in one place and continuously map the same area, but you can map all the space within a disc?
It takes decades however to finish Hohmann transfers that far out apparently.
Rabbithole: Some calculations that may be entirely wrong would suggest that a <10000lbs spacecraft might be held "in place" for 100 yrs with a small fission reactor and an indium-based FEEP drive with about 15lbs propellant.
If you circularize the orbit at 550 AU (which is costly but possible, at ~1km/s of delta-v), then you end up with an orbital period of >10000 years (to complete your whole-sky survey in one plane).
But first-- the price to get that circular orbit is steep, you end up imaging empty space for a lot of the time (no real way to "skip ahead") and your orbital speed vector makes you leave the observation cone for any interesting target pretty quickly.
In conclusion: You probably really want to stick with "one telescope probe per target system", and to give them one-shot orbits because those are cheap, reasonably fast and inside the observation cone (for your single target) for longer.
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.
It would be most likely a whole solar system. Consider that new horizons only had hours during its flyby to collect all the telemetry that it did. Imagine having 600 pixels of resolution for an exo planet for up to 15 years. Plus all the other telemetry you'll be collecting about the galactic space near us.
With a Jupiter/solar oberth boost we can at best do around 20 AU per year, so best case scenario it would take atleast 25 years to get there, which honestly isn’t bad at all. For comparison voyager does around 3.6 AU/year.
A series of permanent stations near the vicinity of the oberth burns at Jupiter and the sun could add a lot of Delta V by firing a laser at the probe and the probe could fire one back. Even more so if it was a series of laser boosters strategically placed around the solar system. The numbers start to get really crazy.
Nuclear-powered ion thrusters could solve this issue. They provide low acceleration for a long time consuming very little consumable. This would allow the telescope to stay at the right position for observation.
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.
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.
I'd argue that it's this same pattern-seeking drive that undergirds science.
"Zeus sends the lightning, his wrath darkening the very sky," is an understandable model that connects "dark storm clouds" to a likely prediction of lightning.
That urge to explain the surprising, to find the pattern, leads directly to our understanding of the cosmos.
>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.
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.
Maybe visiting moon is overrated. We can't know, we have very narrow tube vision centered around our rather primitive lives.
Effectively immortal organisms may be more impressive. Or those surviving in anaerobis boiling water conditions. Or fixing radiation defects like its nothing. Or vacuum. Or...
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.
It's expected that a human would associate life with intelligence, but it's also a bit of a contradiction because it does not seem very intelligent to do so given all we know about the history of life on our planet.
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.
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 was going to make a joke about the aliens returning and presenting us with a bunch of birds.
But that got me thinking, if an intelligence goes around collecting species, how would they keep their specimen populations from evolving? How could they possibly keep so many specimens alive over the eons?
Perhaps their strategy would be to take a vast amount of genetic samples and preserve those species as data. Rather than abduct dozens of T-Rexes for some zoo exhibit, they take the genomes from tens of thousands of T-Rexes and make a population snapshot. After they depart from Earth they could clone or create as many as they want, as needed.
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.
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.
Our nighttime view of the planet has dramatically changed in the past 100 years and is increasing. They would instantly see us using electricity and could possibly see our satellites.
I wonder if there are conscious ants and similar small infrastructure-builders running around on the ground with the exact same ideas. "Of course the big-beings-in-the-sky recognize our tracks here are major roads and agricultural areas, they must understand we're intelligent"
Heh, your flip remark leads to an interesting observation: I think the most obvious signature of "abstract intelligence" is suboptimality. An alien would look at an agricultural grid and wonder, what possible natural process would divide something into squares rather than hexagons? Even without knowing what they are or how they form, it's hard to imagine anything that would prefer such a high energy configuration. Such stupidity implies a system oddly bounded in its ability to optimize, which implies a feeble biological brain trying to do something "on purpose" rather than a natural process.
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.
I'm genuinely curious for someone less lazy than I to do the trigonometry. My gut feeling is these would be tiny apparitions on the edge of the disc. Not visible to the naked eye, even with a shield.
Similar to using everyday objects as pinhole cameras. At certain specific distances and angles my blinds offer magnification of small bits of the trees outside.
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