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I give this to you since I would like informed opinions

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    I’d add that even Phil Plait at the Bad Astronomy blog is willing to say “Did Astronomers Find Evidence of an Alien Civilization? (Probably Not. But Still Cool.)” which is pretty high praise for him, I think.

    http://www.slate.com/blogs/bad_astronomy.html

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      Anytime a headline contains the word alien, you can substitute either ‘people’ or ‘God.’ We don’t have any working model of aliens, so describing something as alien necessarily has an alternate, simpler explanation. If you don’t know what that is, don’t invent aliens. Describe what you’re seeing, not what you’re speculating.

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        My opinion on this is that I’ve never so urgently wanted to know the answer to an astronomy mystery. It sounds like it should be possible to rule out an alien civilization within a year or two, but what IS the explanation? The figure of 22% of the star’s light being blocked at times is absolutely astonishing.

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          Interesting thought: KIC 8462852 is 1481 light-years away. Suppose what we see is, in fact, a bit of a Dyson sphere built by an incipient Kardashev Type II civilization, and we have been observing their solar panel floating in front of their sun. At the time that the events we are observing happened, they could perhaps turn a giant telescope on Earth. What would they see?

          At the time we are observing, the most recent signal they had received from us would be 2962 years ago, about 900 BCE. The Greek Dark Age following the Bronze Age Collapse were starting to come to an end (somebody might still have remembered how to write in Linear B, but the knowledge was dying out), Jeroboam or perhaps David was king in Israel, China under the Zhou Dynasty was developing the Great Seal Script from the oracle-bone script (the Warring States period had not yet started), smelting of iron began, Assyria was a great power, and Zoroaster was born.

          If we were to respond to our discovery of their nascent Dyson sphere by flashing a signal to them, hoping that they would hear it, they would receive it 2962 years after the sphere reached the state we are observing today. That is, their Kardashev Type 2 moment would be as far in the past for them as the Assyrians, King David, the Western Zhou Dynasty, and Linear B are for us. What does a civilization look like three millennia after reaching Kardashev Type 2?

          We might not have to wait 1481 years to meet them, though. Suppose that, if they are not subject to resource constraints, their energy usage grows like ours: roughly a factor of 10 per century. The Milky Way’s 200 billion stars, then, would be harnessed only some 11 or 12 centuries into their future from when they reach Kardashev Type 2 — but most of those stars are fifty thousand light-years away, so failing some kind of superluminal travel, the transition from Type II to Type III will inevitably take at least tens of millennia, not the mere millennium our own growth rate would suggest.

          A Kardashev Type II civilization would have no difficulty launching near-light-speed starwisps to make contact with nearby stars and begin to harness their energy. So if there are citizens of KIC 8462852, perhaps we will meet them soon, within a century or two; roughly estimating, I think there are perhaps a few million stars closer to them than our own.

          You might wonder whether a hypothetical Type II Civilization at KIC 8462852 could detect the Olmec, Zhou, and Assyrian civilizations from a vantage point 1481 miles away. Using only the means of detection we already know about, light would probably be their best chance, specifically ultraviolet at about 300 nanometers — nothing longer can make it out of our atmosphere. The Rayleigh criterion says that it’s pretty hard to see things that are closer together than about 1.22λ/d radians, where λ is the wavelength and d is the diameter of your telescope’s aperture. If you can construct an interferometer several astronomical units across — let’s say 10 AUs across, about the size of the orbit of Jupiter — then you can resolve things down to about 2.4 × 10⁻¹⁹ radians apart. At a distance of 1481 light years, that’s about 3.4 meters.

          So yes, KIC 8462852 could have maps of Bronze Age Earth almost as good as what you can buy from IKONOS satellites today, even before they ventured outside their own solar system. They could have observed the flourishing of the cities of Mesopotamia, the progress of the Bronze Age Collapse, and the gradual degradation of the Great Pyramid at Giza. Every house built, every crop planted, every field cultivated, could figure in their databases in greater resolution than you can find modern crop plantings in the free 15-meter-resolution Landsat 8 data on Earth Explorer. No doubt if they observed these phenomena, they would find them of great interest.

          So it seems likely that we will meet them within decades or centuries — unless they don’t exist.

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              Sounds like a cool mystery, but I think it’s way too early to start throwing around terms like “alien life” or “advanced technical civilization”. I’m guessing a simpler explanation will eventually be found. But part of me wants to hope that it is, indeed, aliens.

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                It’s definitely appropriate to check that possibility, at this point. We could waste a lot of time on other options, if it is artificial structures. And meanwhile, more visual observations are also being talked about, so it’s not as though looking for artificial and natural explanations are mutually exclusive.

                And, I mean, I think the general public seriously underestimates the likelihood that humanity will someday find an alien civilization. It’s a downside of science fiction focusing on scenarios that are clearly impossible; it makes the possible ones seem equally fantastic.

                But yes, it’s very annoying that this is only in the news because somebody saw a chance for that headline. It deserves to be regardless. :)

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                  It’s definitely appropriate to check that possibility, at this point. We could waste a lot of time on other options, if it is artificial structures. And meanwhile, more visual observations are also being talked about, so it’s not as though looking for artificial and natural explanations are mutually exclusive.

                  Sure, absolutely. I’m not saying we shouldn’t continue to investigate this… just the opposite, I think we absolutely should focus some resources on this. Regardless of what the ultimate explanation proves to be, I expect we’ll learn something either way

                  And, I mean, I think the general public seriously underestimates the likelihood that humanity will someday find an alien civilization.

                  Could be. I dunno. I’ve heard good arguments on both side of the “how likely is intelligent alien life” thing. I tend to believe there probably is (or was, or will be) intelligent alien life elsewhere, partly because of how simply HUGE the universe is. OTOH, I am open to the possibility that we may never discover or interact with intelligent alien life for the exact same reason.

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                    Yeah. I guess I’m mostly complaining that it’s a hard topic to discuss because it gets sensationalized.