"Our Exploration And Colonization Of Space: By Human Or By Machine?"," Therefore, UFOs cannot represent the technology of a space-faring race of extraterrestrials.
Sure, space is really BIG! Planet Earth was really BIG to human society many centuries ago, but that didn't stop the planet being explored from pole to pole, even if individual journeys took many years.
Terrestrial analogies aside, what if you have an alien race with life spans way, way surpassing ours? Then there's a possible likely alternative, a bit of the old genetic engineering to increase life expectancy? Or there's the likelihood of enhanced bioengineering (part flesh; part machine) to accomplish the same goal.
There's lots of time available to explore and colonize starting a few light years outward at a time.
Repeat as often as required.
Such velocities, while pretty fast by our current abilities, shouldn't be beyond the means of a technologically advanced race.
And once here (within easy reach of, or in our solar system), having a nearby base of operations as it were, one can easily have a whole plethora of UFOs visiting Earth on a regular or routine basis.
If you want to explore the South Pole over the long term, you don't make a daily commute from Sydney or New York - you set up a long-term base camp near or at the South Pole!
If there are no advanced extraterrestrial races out there, and that's a possibility that has to be considered, then eventually we'll reach that hypothetical level of technology that we current assume aliens might have.
And 1000 years (give or take) is but a nanosecond in terms of cosmic and galactic time frames.
What will another 1000 years bring?
[Note that intergalactic space travel (one galaxy to another galaxy) is quite another can of worms.
Even Star Trek stayed within our own galaxy, and they had warp drive!]
When viewing what exploration of space we've achieved to date, we note that the first pioneers weren't the right stuff, flesh-and-blood human beings, but devices composed of hardier stuff, like metals and plastics.
The unmanned lunar surveyors preceded Project Apollo.
And so that will probably be true as well as humanity extends its reach beyond our solar system.
Then came the industrial revolution and labour got easier and machines took on more and more of the burden.
We don't have to read anymore as we have radio, TV, talking books and DVDs.
We don't need to spell as our PCs come equipped with spell checkers.
And while human muscles and the human brain haven't increased much in strength or potential intellectual capacity over the past multi-thousands of years, our technological muscles and brains have.
And how many of us could beat a computer at chess, or checkers? Silicon chips are becoming 'intelligent' at a vastly faster rate than the brain stuff we are made out of - CHON (Carbon, Hydrogen, Oxygen & Nitrogen).
We've all seen a sci-fi robot, android, whatever.
How much longer before science fiction becomes science fact and silicon software replaces carbon wetware?
The question has been posed whether or not artificial intelligence is the next logical evolutionary step.
So, the question arises, why send CHON flesh-and-blood into space when silicon chips and software will do, and do better? It's been argued that artificial intelligence can make the trip to the stars on our behalf.
They can exist on a minimal energy source, nuclear most likely.
'reproduce' themselves from internal programming given before the fact, and thus spread throughout the galaxy.
Meantime, while they do all the dangerous dirty work, we humans just continue to inhabit Terra and live the good life.
Firstly, it's going to take a lot to extinguish the human spirit of exploration.
Secondly, I find it difficult to visualize a space probe, however artificially intelligent, that can somehow reproduce itself from scratch using the raw resources of another planet.
Just visualize the various technological processes that would require.
I won't say it can't happen, but I somehow doubt it will happen.
Again, for the purposes of explaining the Fermi Paradox, there exists no extraterrestrial CHON, only terrestrial CHON, so that explains the 'where is everybody?' question.
For quite some considerable time now, we've augmented our flesh-and-blood with artificial materials and devices, cosmetic and life enhancing - plastic heart valves, hearing aids, artificial joints, wigs, dentures, etc.
So, sooner or later, humanity's flesh-and-blood, assuming we're still flesh-and-blood and not composed mainly of sturdier materials (CHON plus iron and silicon and plastics and ceramics, etc.
That's true even if we have evolved into something more akin to a hybrid of the biological and the artificial, and/or evolved ourselves into a race of quasi-supermen (and women).
Might there be something even stronger forcing us to 'boldly go'?
So what's that other more seriously driving incentive to 'boldly go.
Wanting to vacation on some idyllic planet around another star system is fine, but extra-solar tourism is a luxury, not a necessity.
No star lasts forever.
In fact, sooner or later, our sun will be the death of us all.
Finding a suitable one is going to call for us to be 'boldly going.
; Interstellar Travel: Past, Present, and Future; Stein and Day, New York; 1977:
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