The aliens are probably in a state of suspended animation.
Today, perhaps, only a few scientists believe that Earth is the only place in the Universe where life in all its diversity exists. Astronomers regularly discover potentially habitable or at least habitable exoplanets, but humanity still has no evidence of the existence of extraterrestrial life. A study carried out within the framework of the SETI project (search for extraterrestrial life) shows that the probability of the existence of highly developed extraterrestrial civilizations is extremely high, but we cannot make contact with them due to the fact that they are experiencing, for example, climate change . On distant exoplanets, as well as on Earth, seasons also change, weather conditions are transformed, and, most likely, not for the better. Probably, extraterrestrial civilizations found themselves in a situation where their planets became practically unsuitable for ordinary life. To survive a difficult and life-threatening period, progressive ali...