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this post was submitted on 14 Jan 2024
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UFOs have always been real, they've never been alien. It's just an unknown object of phenomenon being detected.
An alien civilization sophisticated enough to travel to earth would be emitting radios waves for hundreds if not thousands of years prior. Earth is covered in a wide array of telescopes pointed at space and we haven't heard anything yet. In fact some suspected cases turned out to be microwaves in the break room and oscillating black holes, none aliens.
It's likely we are the first sophisticated civilisation able to travel to another planet, and we are no where near travelling outside our solar system never mind our galaxy.
We probably wouldn't know the signals when we see them.
It assumes that alien civilizations would be broadcasting regular repeating signals at high power. In my lifetime we've moved from high power repetitious analog signals to much lower power digitally encrypted and compressed signals.
Encrypted and compressed signals look random to an observer who doesn't know the keys/algorithms. On top of that, we've moved from individual huge transmitters (e.g. TV stations) to a plethora of tiny transmitters (e.g. cell phones). In a single human lifetime.
If we don't scorch our civilization out of existence, we'll adopt even lower power communication systems: point to point lasers, CPU-intensive encoding systems, and probably even more exotic stuff. Our signals will disappear into the background noise of space.
We don't know what to look for.
I'm in full agreement with this one.
We have higher and higher output signals. Your assuming the WiFi signals in homes now represent all the signals humans output, this isn't the case by far.
An encoded signal still appears as a manmade signal and not the result of a natural phenomenon.
Any alien civilization that travels between planets or solar systems would have multiple high gain networks.
Even if they used lasers, that would make detection easier. Lasers are not a natural phenomenon. If we observed one in nature that would be a new mechanism or evidence of alien life.
Not at all. We're still spewing out commercial radio, and TV. But we're slowly converting them from analog to digital, which uses much less power.
Many of our digital signals are spread spectrum, hopping across a wider spectrum than analog. Distinguishing our own frequency hopping signals from noise is difficult, and an active area of research. If aliens use a similar technology, it seems unlikely that we would notice them.
The sky is huge. It seems highly unlikely that we would happen to have a compatible detector pointed in the right direction at the right time. Even if we did, the signal would probably be compressed (meaning that its modulation would look like noise) and the lowest possible output, meaning it would probably blend into the background.
You realize humans have only had the ability to search for aliens using electronic equipment for less than 200 years right?
The universe is ~14 billion years old. The earth is only ~4 billion years old. Humanity is only ~200,000 years old.
You need to read about the Fermi paradox. The likelihood of extraterrestrial life existing is a mathematical certainty. We just haven't seen any due to a multitude of factors.
You're mixing up the Fermi paradox and the Drake equation.
Assuming you meant the Drake equation, more than half of the variables we have absolutely no statistical basis to decide on a fraction. Obviously they are non-zero, but they could be extremely improbable. We only have one example of intelligent life developing radio communications. Any estimate of a statistical likelihood of that using Earth as an example is meaningless without other examples.
Some pessimistic estimates give solutions as small 9.1 x 10^-13 which indicates we would be alone.
The Fermi Paradox riffs on the optimistic answer to Drake's Equation. If other intelligent life is a certainty, why haven't we found them yet?
If it existed within our observable limits we are likely to have heard of it.
The Fermi paradox doesn't imply sophisticated alien life exists on earth.
Of all observations we have have only found one species able to leave their planet deliberately. That's humans. There no evidence of any species leaving their solar system. Humans have never went beyond the moon, other than robots. Only one of which has reached the end of the solar system, but not entering another.
We also have no evidence of life on another planet to base any calculations on. The best estimate of life existing anywhere else is zero. You need another observation per planet to make any realistic estimate.
People are biased even physicts by the desire for extraterrestrial life. It adults looking for a father figure, we had god but once we went beyond the clouds and developed the ability to explain most phenomenon people look for a replacement. Someone to explain all our problems and give us solutions.