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Comets Can't Explain Weird 'Alien Megastructure' Star After All (newscientist.com)
schwit1 sends the latest news about KIC 8462852, the star that that led many to learn what a Dyson Sphere is. New Scientist reports: "The weirdest star in the cosmos just got a lot weirder. And yes, it might be aliens. Known as KIC 8462852, or Tabby's star, it has been baffling astronomers for the past few months after a team of researchers noticed its light seemed to be dipping in brightness in bizarre ways. Proposed explanations ranged from a cloud of comets to orbiting 'alien megastructures'. Now an analysis of historical observations reveals the star has been gradually dimming for over a century, leaving everyone scratching their heads as to the cause. Bradley Schaefer of Louisiana State University saw the same century-long dimming in his manual readings, and calculated that it would require 648,000 comets, each 200 kilometres wide, to have passed by the star — completely implausible, he says. 'The comet-family idea was reasonably put forth as the best of the proposals, even while acknowledging that they all were a poor lot,' he says. 'But now we have a refutation of the idea, and indeed, of all published ideas.' 'This presents some trouble for the comet hypothesis,' says Boyajian. 'We need more data through continuous monitoring to figure out what is going on.' What about those alien megastructures? Schafer is unconvinced. 'The alien-megastructure idea runs wrong with my new observations,' he says, as he thinks even advanced aliens wouldn't be able to build something capable of covering a fifth of a star in just a century. What's more, such an object should radiate light absorbed from the star as heat, but the infrared signal from Tabby's star appears normal, he says."
> So right here, on planet Earth, the same types of people - scientists - are incapable of understanding how a large structure the size of the pyramids was built a couple thousand years ago..
There are lots of theories; there's no particular surprise that they were able to, but we don't know exactly how it was done because it was a long time ago and the Egyptian engineers didn't leave very good records. Nobody is going to be able to prove within a shadow of a doubt how it was done, but there are lots of plausible ways it could have been done.
https://en.wikipedia.org/wiki/Egyptian_pyramid_construction_techniques#Construction_method_hypotheses
Our star loses one billion kilograms per second... While that may sound like a lot... It's still only an earth mass every 150 million years. The math doesn't work out. Additional matter would need to come from somewhere.
Thirty four characters live here.
but you would need to mine 100 planets like mars in the time, kind of.
Nope. Just one is enough. To build a Dyson sphere at one AU (the distance of the earth from the sun), or about 150,000,000 km, the sphere would have an area of 4 * pi * r^2 = 9e23 m^2. The mass of Mars is 6.39 × 10^23 kg. So if you build the sphere with a mass of about 1 kg / meter squared, you could do it with just a little over one Mars sized planet.