Modern people are accustomed to considering dreams a product of their own mind, a game of the subconscious, a set of experienced impressions, and do not suspect that much in the world of dreams goes beyond this theory. Perhaps, falling asleep, we find ourselves in another world with our own nature, where different physical laws apply. Dreams about nature are similar in many ways. A few suns in the sky or no sun at all, but brightly lit, as if during the day, clouds of unusual colors, tiny stars falling from the sky like hail, unnaturally bright seas, waves reaching great heights - these details coincide in the dreams of many people who have never met each other. Perhaps we live in two worlds - in sleep and in reality - and move between them at the moment of falling asleep and waking up.