Mankind is limited by what it knows to be real, what it has devised a way to measure, and what it can categorize into its perception. As we venture further into the unknown of space we will no doubt see and experience things, incomprehensible things, that defy the structure of what we've defined as reality. While speculation is fun, the reality that we may have actually come across something mankind previously has not seen or even ever thought of is as exciting as its is intimidating.

We've only just begun -- to quote the song. Most "science" prior to the mid 19th century is pretty much useless. Only in the last 100 to 150 years have we made any real scientific progress, and then only sticking our toes in the water's edge of a great ocean. If we remain a viable species, there is no limit to what we will discover, and I'd be willing to bet that includes everything deemed "impossible" today. While I don't accept wild-eyed speculation, I have no doubt the universe doesn't accept "I can't." By the way, as to Hawking's caution, I can only say that his attitude of not attracting attention to ourselves would keep us in caves without fire unless we found it through no efforts of our own.

If there are aliens living there, I hope we're not in too big a hurry to tell them we're here. They might be hostile, and able to conquer or destroy us. Let's at least listen a while first.

this is good -- when do we leave??? -- j
.

Yesterday I was sitting with some office-mates at lunch discussing this. I made the point...What do you think more intelligent life would think of us if they have been watching us earthlings over the past several decades? I think they'd think we were a bunch of morons. I came to this conclusion based on a speech I recently attended by a retired astronaut. He is currently working on a globally-orchestrated effort to develop a method to deflect large (extinction-causing) asteroids. His biggest problem?...Getting the different nations to come together over this one issue. We simply can't do it. I'll not get into the more technical facets that really do require a multination agreement. Anyway...makes me chuckle...

"but could be the biggest news in human history."
Therefore, regardless of the facts, it will be reported as ... nothing.

Maybe we don't see radio waves from other civilizations because they very briefly use high-power radio and then abandon it for repeater based systems or other communications media. That's happening on earth.

So then they don't become visible until they build something like this sliver of a Dyson sphere they're imagining. It's hard to get my mind around it. I imagine them developing long-lived probes that would go out and find civilizations, both living and long-gone. I imagine them still being confined to their solar system by Special Relativity but having very long lifespans.

I can imagine them getting data back sent from one of their probes. They haven't visited Earth yet. This data is from some civilization on a planet with a thin atmosphere and less gravity. They developed a gestural and written language (the atmosphere being too thin for speech), began to urbanize, and then plague followed by a glacial period wiped them out, leaving the planet to non-intelligent animals.

If such a civilization existed 1500 light years away and we're seeing something they were building 1500 years ago, are we on a list of Goldilocks planets to visit. There are no radio waves. They can't zoom in an see the Holy Roman Empire, Byzantine Empire, or the civilizations in the Americas. By the time their probes get here, maybe they'll find our own energy collecting system and a civilization of people linked together by artificial brain interfaces, living thousands of years. I can't fathom whether any future humans would be weird enough to set out and spend its 3000 year lifetime on a trip to see KIC in person once they know someone is there.

From a hard science perspective, Where are all the aliens? It's called the Fermi Paradox, with billions of galaxies, each with billions of stars, why haven't we found sign of them yet?

Personally, I think they wouldn't care about us. I mean do you go up and try to communicate with every barking dog? Maybe the only way we would get their attention would be to show up on their doorstep. Even then, they might just call animal control. 😸

I don't deny that there is a possibility that outer-
space people exist, or that they have possibly been
here before. But I don't think any of the specific
cases claimed are such.

Even if they do exist, I don't think they really
should come here. Even on this planet, you are
not allowed to just go from country to country
without a passport (except I understand that there is some sort of agreement between Cana-
da and the U.S.). One reason is the possibility
of spreading diseases; a medical exam is need-
ed. Who knows what kind of plagues they could
bring down here, or for that matter, take back to
their own people? (Then again, a germ in such
a being might not be able to survive in a human.
But who knows? And if if could blight plants and
crops...)

I'm reminded of the Dyson sphere concept, which postulated the growth of a planetary system structure to capture as much as possible of the local star's energy. Dyson suggested that a complete system might even hide the star's emissions. Is this the first evidence of a Dyson sphere under construction?