And there is the added complication of, If Aliens are here why are they hiding? Are you hiding from the ants living in your lawn? Probably not. So why haven't they just started making their presence obvious, like visiting shopping malls, or building mile-wide space stations in orbit, or carving a smiley-face on the near side of the Moon?
And if they were here in the past, where is the trash they left behind? Surely they would have carved that smiley-face on the Moon as a "KIlroy was here" marking for the next space traveling race to pass by to see. Or the remains of a temporary base on the near-side of the Moon?
The idea of sending signals and hoping to receive something back from an advanced civilization is, sadly, a waste of time, if the receiver can't conquer such distances with ease (and having the same development we have is already beating improbable odds, anything could have happened in those millions of years to prevent our existence). It's not a question of "if", it's when killer asteroids or other life-threatening events can shake a planet. And wipe an entire species.
What we are transmitting out there is probably not going to be interpreted properly, the signal will likely degrade and confused with other stuff (the "WOW signal" has been "debunked"). Voyager 1 isn't going to be found, I also doubt the materials used in it will remain intact for more than a few decades.
If an alien notices planet Earth exists (there's no such thing as "visiting", because that assumes they know about our existence beforehand), and waste their time spending resources flying into outer space hoping to find anything at all (considering it's mostly empty, and also assuming their bodies don't get destroyed in the trip), most of what they'll see when looking at us is...
WATER.
Calling it "Earth" is misleading. About 71% of this planet's surface is covered by oceans. The remaining 29% is land. And even that is mostly deserts, mountains, forests, and ice. Urbanized or populated areas, cities, roads, etc. make up less than 1% of Earth's total surface. From orbit, or from another planet's vantage point, the blue color of oceans dominates the view. That's why Earth is nicknamed "The Blue Planet".
And that tiny percentage is shared with animals that I view as we all do ants, in terms of how they can have meaningful communications with us.
Why would you (if you were an ET, capable of creating such spaceships) land in here? To get captured/harmed? What if the first thing you see is a dumb animal (aside from humans)? Remember the aliens don't know a single thing about us?
The fact we are mostly WATER is a strong reason to suspect that's only what they are seeing from such distances (that is, if their telescope/other instruments can detect traces of life from Earth - depending on the distance, within our solar system, we may see ourselves as pixels). If the beings piloting or controlling these crafts are indeed aliens, they do whatever they need, and move on. Jumping through dimensions, or not.
After decades of UFO reports, that's the only consistent behavior - these objects are elusive and will never allow themselves to be intercepted.
It's also the "move on" part that always "breaks" these discussions.
Because there's no evidence they are hiding in here, or in outer space, close to this planet (and I mean really close, perhaps hundreds of km above our heads).
That also implies they left their home planet, since it has been discarded (from what has been said in the previous posts) travelling close to the speed of light, into another dimension and other sci-fi wildish theories.
"Where would they go" is never explained (don't tell me it's underwater...). I don't buy the "we found the alien crafts and keep them in our basement" stories.
What we can all agree is that at least the aliens that pay us a visit are always shy, or know better, to interact with us.
That's no different from most animals, they don't knock on our door to get an invitation for tea, and talk about politics, philosophy. Whatever any animal does is aimed to survive, get more resources, reproduce, and perhaps gather some information about the environment. That's all. We are the ones that anthropomorphize them. We are the ones guilty of thinking aliens, if they exist, will act as we would. No. That's projecting.
As for what evidence would convince a skeptic, I don't think I have seen discussed enough how it's a waste of time trying to capture/record UFOs moving so fast. All equipment suggested to do such a thing, and all "evidence" I have seen (Mick and others that dealt with these can attest to what I am saying a lot better than I do) are pathetic (with all due respect - it's not the people that try/took them that I have an issue, they have my simpathy - it's with the tech that is shit).
For example, astronomers and astrophotographers are the last that can produce such evidence. You always need to spend a lot of cash to get anything worthwhile (remember it's also not exactly portable), and when you least except, said UFO will appear when you are not ready. I am not even counting Photoshop and now AI manipulation. We simply cannot produce convicing images of UFOs, period.
Every UFO picture is a fuzzy blob, blurry and useless, when it's not among the many fakes produced by grifters, which sustain this "industry".
In order to do a proper capture, these UFOs would need to spend considerable time not moving (like a deep space object when we try to capture them at night), just hovering, the conditions of the sky help (they never do... especially at night, that makes these a trillion times worse), not putting so much distance from us, not being so small, and the tech we have, be adjusted accordingly in perhaps seconds; I doubt most people not only own such gear $$$$$$$ or are ready for any of these encounters, all the time.
As for not being ready: in the 2004's Tic-Tac incident, the jets had helmet-mounted sights (HMS) and head-tracking sensors integrated with the aircraft's targeting systems, including the ATFLIR pod, which records video and infrared imagery. The pilot can "slave" the targeting pod or radar to wherever they look, using the helmet system, so the sensors automatically point where the pilot's head is turned.
David Fravor said in one of his videos (check on Youtube), that he didn't activate it while looking the object. When he said he didn't "turn his head camera on and regretted now", he meant he didn't switch on or cue the ATFLIR targeting pod during the encounter.
That's because at that moment, he was visually maneuvering against the unknown object at low altitude over the ocean, in a tight, dynamic aerial engagement. Engaging the helmet cueing or heads-down camera systems would have required looking inside the cockpit to operate menus or buttons, or turning his head and focusing on the HMS display rather than the outside horizon, which he hinted that was a recipe for spatial disorientation, especially when the aircraft is banking, descending, or pulling G-forces.
So, you see, that illustrates there's always some obstacle to get a clear picture of said UFOs, and it's not like our tech is crap, it's that we are not ready (or at lest until now, unable) to produce convincing evidence.
