In the universe there are many inhabitable planets. The Russian schoolmaster and physicist foresaw elements of the space community in his book . Tsiolkovsky had his space travelers building greenhouses and raising crops in Space. Tsiolkovsky believed that going into Space would help perfect human beings, leading to immortality and peace. "Earth - the cradle of humanity, but one can not eternally live in a cradle!" - he wrote.
book "Beyond Planet Earth"