Comment They know we are here then? (Score 1) 211
So, their astronomers less than a 50 light years away ran their version of Kepler, looked at Sol, found Sol-5 and Sol-6, and with some luck Sol-3 and they noticed the liquid water fingerprint and selected it as a likely candidate for a life-hosting planet. Then they made more and better observations and they found the CFC fingerprint and figured that Sol-3 must have a technological civilization living there.
What do they do next? Build their version of SKA and point it at Sol-3 hoping to catch radio signals? There won't be much to find yet. They probably need to keep observing for another 20 years at least. What if they looked 100 years too early? They would have noticed the water, but not much more. They might be able to figure out that Sol-3's atmosphere is mostly nitrogen and oxygen. Will they keep observing in the hopes that something interesting happens? How soon will they be able to notice the subtle changes in the atmosphere's composition?
What do they do next? Build their version of SKA and point it at Sol-3 hoping to catch radio signals? There won't be much to find yet. They probably need to keep observing for another 20 years at least. What if they looked 100 years too early? They would have noticed the water, but not much more. They might be able to figure out that Sol-3's atmosphere is mostly nitrogen and oxygen. Will they keep observing in the hopes that something interesting happens? How soon will they be able to notice the subtle changes in the atmosphere's composition?
