I Have Always Believed Aliens Are Real
I find myself less and less interested in starting a conversation about aliens with UFOs.
Not because UFOs are not worth studying, but because they often reduce a genuinely enormous question to a few shaky videos, a dot on a radar screen, or someone saying they saw something.
And in the end, everyone ends up arguing about the same thing:
Was that an alien spacecraft?
I am actually more interested in a different question.
If no flying saucer had ever landed on Earth, if there were no secret bases, no alien bodies hidden by governments, and even if every famous UFO case eventually turned out to have an ordinary explanation, would there still be other life somewhere in the universe?
My answer would still be yes. I believe there is.
But when I say “believe,” I do not mean “I know.”
As of now, humanity has not confirmed a second, independently originated form of life. NASA has been very clear about this: there is no credible evidence of extraterrestrial life, and no evidence that unexplained UAPs are extraterrestrial in origin. AARO, the U.S. office responsible for investigating these incidents, has likewise found no verifiable evidence of extraterrestrial beings, activity, or technology.
If the evidence stopped there, the story could probably end.
But astronomy over the past thirty years has made it much harder to leave the question there.
In 1995, humanity confirmed the first exoplanet orbiting a Sun-like star. More than thirty years later, NASA’s confirmed count has passed 6,000. What matters more than the number itself is what we have gradually learned from it: having planets does not seem to be some unusual piece of luck that happened only around our Sun. Planetary systems appear to be a very ordinary product of the galaxy.
Data from Kepler even led researchers to estimate that the Milky Way could contain at least around 300 million worlds orbiting Sun-like stars, roughly rocky-planet sized and located within their stars’ habitable zones. That number has to be handled carefully. It does not mean there are 300 million “second Earths,” and certainly not 300 million planets with life. New methodological research published in 2025 was still reminding us how difficult it is to estimate how common these planets really are. Different methods can produce estimates that differ by more than an order of magnitude.
But even after stripping away every exaggerated version of that claim, one fact remains:
The universe does not seem to be short of stages.
What we do not know is how difficult it is for the actors to appear.
This is the step that I think many arguments for “aliens must exist” skip over too easily.
Liquid water is not life.
Organic molecules are not life.
Carbon is not life.
Phosphorus is not life either.
Even if you put everything life needs in the same place, that does not mean those ingredients will automatically turn themselves into life.
Enceladus is a good reminder of this. Cassini’s analysis of ice grains from the plumes of this moon of Saturn found phosphates coming from its underground ocean, and researchers estimated that phosphorus could be present there in surprisingly high concentrations. Water, chemical elements, sources of energy – we are slowly assembling the kind of potentially habitable environment that once existed only in imagination.
And yet, in the end, all we can still say is:
It may be suitable for life.
We cannot say there is life there.
Mars is the same. Perseverance found structures and chemical combinations in a rock called Cheyava Falls that were formally described in a peer-reviewed 2025 study as “potential biosignatures.”
That is an important word.
Potential.
Because similar features could still form through chemical processes that do not involve life. NASA itself has explicitly kept those explanations open.
I actually like this almost frustrating level of scientific caution.
The K2–18 b story in 2025 was an especially good example.
Early JWST analysis reported a possible signal of DMS or DMDS. These molecules were exciting because, in Earth’s environment, they are closely associated with biological activity. News coverage quickly started talking about what might be “the strongest sign of extraterrestrial life yet.”
Then other research teams started taking the claim apart.
They reprocessed the data.
They changed the models.
They checked instrument noise.
They added other molecules that could absorb light in the same wavelength range.
By the time later independent analyses came out, the DMS/DMDS signal could no longer survive as a stable, statistically meaningful detection. Further work in 2026 also showed that the existing atmospheric data could be explained without invoking DMS at all.
Someone who really wants extraterrestrial life to be real could find that disappointing.
My reaction is almost the opposite.
It makes me more confident that, if we ever do make a genuine discovery, it might actually hold up.
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Because if even the answer we most want to be true is attacked from every possible direction, then the result that eventually refuses to fall apart is the one that will really deserve to be believed.
That leaves us with the most difficult part of the whole problem.
We simply do not know how hard it is for life to emerge from non-living chemistry.
We have only one known example: Earth.
Life appeared relatively early on Earth, which sounds encouraging. Maybe once the conditions are right, life appears easily. But statisticians and astrobiology researchers have pointed out for years that there is a selection effect here. Any observers capable of sitting around discussing this question can only exist on a world where life successfully appeared early enough to leave enough time for those observers to eventually evolve.
With only Earth as our sample, it is very hard to work backwards and estimate how often life begins across the universe.
That is also why I do not like saying, “Statistically, aliens almost certainly exist.”
We are not really in a position to say “almost certainly.”
We do not even know what number to put into the most important probability.
Life might emerge very easily when the environment is right.
Or it might be unbelievably rare.
The transition from simple life to complex cells might be another barrier.
Complex life becoming intelligent life might be another.
And intelligent life developing into a technological civilization that can be detected across interstellar distances would have to pass through even more filters.
At each step, my confidence goes down a little.
If I had to bet right now, I would put most of my money on simple life having existed, or still existing, somewhere in the universe.
For intelligent life, I would still bet yes, but with much less money.
As for whether an alien civilization has ever visited Earth, I would not place a bet at the moment.
Because that is no longer the same question.
“There is another civilization somewhere in the galaxy” and “that civilization has crossed interstellar space and reached Earth” are separated by physics, time, the lifespan of civilizations, methods of travel, and enormous distances. We are not even close to having searched thoroughly for technological civilizations. SETI researchers have compared the parameter space we have searched to examining a small pool of water out of all the oceans on Earth. Not finding a fish in that pool is not enough to prove that there are no fish in the ocean.
But the reverse is also true.
We cannot call every shadow on the surface a fish just because the ocean is huge.
That is probably the most stable version of my view on aliens.
I believe they exist, but I do not need them to have visited us.
I do not need a blurry video to keep that belief alive, and I do not need to fill every unexplained thing with the words “alien civilization.”
Even if we still find nothing over the next few decades, I hope I would be willing to lower my confidence instead of constantly inventing new reasons to protect what I already believe.
Because what fascinates me has never really been, “I finally proved that I was right all along.”
It is that humanity has arrived at a very strange point.
A little over thirty years ago, we did not even know whether planets outside our Solar System were common.
Today, we are beginning to read molecules in the atmospheres of distant planets, examine chemical traces left on Mars billions of years ago, and search for the elements needed for life inside ice grains spraying out of a small moon of Saturn.
We still have not found a second example of life.
There is no reason to dress that fact up.
But the ancient question – “Are we alone?” – is slowly changing from a philosophical question into something we can actually point instruments at and try to answer.
If the answer ever comes, I suspect it will not look anything like the movies.
No enormous spacecraft.
No White House lawn.
No entire planet looking up at the sky at the same time.
It might just be a very boring set of data.
A spectrum.
A rock.
A sample.
And then a group of scientists spending years trying every possible way to prove that it is wrong.
Until eventually, they fail.
At that point, I suppose we will no longer need the word “believe.”
