Astrophysicist Jonty Horner: Aliens almost certainly exist – but they are too far away (2 photos)

This article is an adaptation and compilation of astrophysicist Jonty Horner's ideas, based on his public speeches, articles, and commentary on the chances of finding extraterrestrial life. The narrative will be told in the first person to preserve the author's logic and tone.





To the question "Are there aliens?" I would unequivocally answer: yes. But a properly formulated question should be: are they close enough for us to notice them at all?

Space is monstrously vast. And over the past decades, we've learned something important: almost every star has planets. The Milky Way alone contains about 400 billion stars. If we imagine that each star has, on average, several planets, then even within our own galaxy there are trillions of worlds. And there are so many galaxies in the Universe that, by some estimates, their number in the observable Universe alone is comparable to the number of planets in our own Milky Way.

At such a scale, it's hard to believe that Earth is unique. Life, including intelligent and even technological life, almost certainly arose elsewhere. But this inspiring story has a troubling aspect for us (scientists): existing and being detected are two different things.

Imagine an extremely conservative scenario. Let's say technologically advanced life emerges around only one in a billion stars. Even then, the Milky Way would still contain about 400 "technological" star systems. This sounds reassuringly large until you consider the size of the Galaxy: approximately 100,000 light-years in diameter. Under these circumstances, these civilizations would be, on average, about 10,000 light-years apart (this is a rough estimate, but orders of magnitude are more important than precision here).



And that's practically a death sentence for the search. At such distances, "normal" radio signals—like those humanity unknowingly scatters into space—are too weak. They can only be detected if the alien transmitters are far more powerful than anything we can create, and if we know exactly where and when to "look."

That's why I believe that extraterrestrial life (including intelligent life) most likely exists, but evidence of its existence may not appear for a very long time. Not because we are alone in the Universe, but because the cosmos is structured in such a way that even our galactic neighbors are difficult to "hear."