Posted by fuidani 2 days ago
Failing that, you’d need thousands of optical interferometers larger than the Hubble spread across a distance wider than the Earth.
My math is below.
Note: I'm not an astronomer.
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The angular resolution limit for a telescope is roughly the wavelength of the light it's sensitive to over the diameter.
If we want to sense things 10m across, with light at the shorter end of the visible spectrum (400 nm), we'd need a telescope with a diameter of about 1/4th of an AU (i.e. the distance from the earth to the sun), around 40 million kilometers.
More practically we could use a telescope array with this diameter, which could conveniently be in lot of orbits about 1 AU out. But the area is still a problem: assuming this 100m^2 object is as bright as it would be on earth under midday sun, it's going to be reflecting around 100 kw of energy. One of these photons has an energy of around 3 eV, so we're getting 2e23 of them a second. Unfortunately these spread out over a sphere with a surface area of 1e31 km^2 by the time they reach earth, meaning we see one every second if we have a telescope array with an area of 50 million square km.
Ok, so let's go kind of sci-fi and say we can build a 30 km diameter space telescope. It would be impressive (and unprecedented) but since it's floating in space and could be made of thin material you might be able to imagine it with today's technology and a lot of coordination. That gets us around 1000 square km! Now we just do it 50,000 more times.
Great, now we have 1 Hz of photons coming from each 100 m^2 patch of Alien Manhattan! I'm sure in the process of building 50k mega-projects we'll figure out a way to filter out the noise, and with a few years of integration we'll have a nice snapshot!
[1] https://www.goodreads.com/book/show/180506.If_the_Universe_I...
Of course, the weak link here is the assumption that these bio-markers can't be produced abiotically, which is a pretty big assumption. Our understanding of planetary science is still in its infancy. This is (thought to be) a hycean planet, a type of planet unknown to us until very recently(post-JWST, I believe?). And given that the solar system has no hycean planets, it's a class of planets which is fundamentally poorly studied, with pretty limited access to data. We can make models, and we can get some spectral data on the contents of their gaseous atmospheres. But we have no way of looking at their surface oceans. Thinking about what kind of chemistry might be going on there is mostly just an act of speculative modelling.
So the interesting question is, without new sources of data, can we determine whether these bio-markers are biological in origin? Not really. Not without a much better understanding of planetary science in general and hycean worlds in particular(of course, that's what this research is trying to do, and making progress at). As well as a deeper understanding of abiogenesis. I could imagine a working understanding of abiogenesis at least being able to eliminate some candidate planets, but even that assumes only one type of abiogenesis is possible, which is more or less unfounded. That is, unless the understanding includes some deep information theoretic/evolutionary perspective on abiogenesis which would probably have to include a completely unambiguous information theoretic and physical definition of what life even is. It is conceivable that such an understanding might provide very strong restrictions on what kinds of chemical systems are capable of abiogenesis, and that those restrictions could then be used to eliminate certain planets or even entire star systems from contention. And if these hycean worlds were eliminated that way, we'd know there must be some abiotic source of these "biomarkers", and knowing that, we would likely be able to figure out what it is. But ok, that's a lot of assumptions.
Maybe we get lucky, and some chemists stumble on a non-biotic chemical system that can produce these chmicals in concentrations that can be detected by JWST at a distance of hundreds of light years. Or, conversely, maybe chemists somehow manage to prove conclusively that biotic origin is the only possible source. I'm not a chemist or a microbiologist, so I have no idea what that would look like. It's probably well beyond our current understanding.
I guess what I'm rantingly saying is, while this result changes my credence that there's life on this planet about as much as is possible with current science and technology, it still barely changes it at all. Before it was maybe 0.5 + ε(habitable zone, liquid water), and it is now 0.5 + 2ε.
I guess something which could move the needle much more significantly, is if we found a large number(say 10) of chemically unrelated potential bio-markers in the atmosphere of a planet very similar to earth, in a very similar star system. Then, the assumption of the impossibility of abiotic sources would be much more plausible. I believe doing this type of research for earth-sized exoplanets with JWST is still quite borderline(please correct me if I'm wrong).
Having said all that, this result is still extremely exciting. For the first time, the field of exobiology has any contact with observational data from outside our solar system at all(besides mere astronomical data), and things will only improve from here. Future telescopes will be better at this type of observation, and our understanding of planetary science is evolving at an accelerating pace. I'm very excited to see where this research goes in the future.
There was this post on HN that life can't be given to mars for 99.99% and even if it could, it would be the most miserable life with only 1-2 decades. It isn't self sustainable as people imagine it to be.
So all we have is, is this Earth & our fellow human beings & instead of treating each other with basic necessities like housing, education , healthcare.
Also these things, in my opinion of researching the space and giving housing, they aren't mutual. They can both be done but even if they are mutual,I would personally pick housing any day, because what point is of space, what point is of going to outer space some day and living shit there if humans are currently living shit here as well.
Regarding Housing, I think it can easily be fixed and so much more like how we say tax the rich, if we could just tax lands.
Because people think of land as some "asset" and that they "own it" ,when in actuality, I might argue that land is the only thing that I personally think the govt. has any right over. So I personally believe that we are better off taxing land so that these pesty landlords who get rich off of the housing crisis can really just suffer so much that the lands would just be productive and not speculative , reducing the price of lands down and even rents down till the point housing is way more favourable.
Its a net win to everybody except those pesty landlords & maybe "investors" or people who bought housing pre-georgism because they might now believe that its unfair to them? Still I think that georgism is pretty flexible and this could be sorted out in such a way that it would have been less controversial and more net positive to the Society than the latest tariffs fiasco, though people didn't vote for housing, they voted for tariffs.