That there could be other planets and other worlds outside our solar system, even without today’s incredible astronomical knowledge, has been thought about for centuries. Giordano Bruno he tried to say it, but as we know it cost him dearly. In fact, only in the last three decades have we begun to see the first exoplanets, planets that orbit around other stars, with a specific purpose: to find a habitable one, in which life is possible.
Eight years ago there was a lot of talk about Trappist 1bplanet of the star Trappist 1, a red dwarf “only” forty light years away. I say “only” because in cosmic terms it is very close, although forty light years means that light, traveling at three hundred thousand kilometers per second, takes forty years to go there and another forty to return. In any case, for Trappist 1b there is a contradiction compared to the data collected in 2013 by the James Web Telescope. In fact, if it was believed to be a dead, rocky planet without an atmosphere and without life, a study by the Max Planck Institute for Astronomy, analyzing different wavelengths, could reveal a planet with volcanic activity and an atmosphere dense with carbon dioxide. It could be, scientists say, an atmosphere never observed before.
We have technological limits for the observation of planets close to other stars: we can in fact observe them only when the planet passes in front of the star, reducing its brightness and analyzing the wavelength. But think about our Galaxy, the Milky Way: it has a diameter of one hundred thousand light years, and we will never see most of the billions of billions of planets. Of the two hundred billion galaxies in the visible Universe, the twin galaxy to ours is Andromeda, two and a half million light years away, and directed towards the Milky Way. The two galaxies will collide in five billion years, and nothing will happen, because the stars are so far apart that they will simply mix. In the meantime, however, our Sun will have already exploded.
So, Trappist 1b? Well, it’s certainly not habitable for us (not even for a trapper), and in any case, despite being astronomically close, it’s too far away. Consider that the Voyager 1 and Voyager 2 probes, launched in 1977, are now just outside the solar system, twenty and a half billion kilometers away from us. To get to the nearest star, Proxima Centaurijust four light years away, it would take eighty thousand years. Among other things, if we received a message from an intelligent civilization a billion light years away, it could have already become extinct, and if we replied they would receive it in a billion years, when we will have become extinct, absorbed by the Sun. «Hey, hello , we were here!». “Us too.” Click, all reduced to dust (for no other reason they say we are stardust).
For astronomers, however, everything is beautiful, and I understand them, every discovery electrifies them.
Even when Giacomo Leopardi wrote The infinite he could think “and it’s sweet for me to be shipwrecked in this sea”, and he certainly wasn’t someone who deluded himself, on the contrary. Today I would say that it is increasingly terrifying. On the other hand, on our Earth we’re not doing so well, where the hell do we want to go. Anyway, happy holidays eh.