This book tells about how distant worlds are explored: the Moon, the Sun, planets, stars, star islands. From it we learn what our knowledge of these worlds in the past and what data about them has advanced science - astronomy - in our days. Astronomy teaches us to understand the relationship between space and time Studying distant worlds, we come to understand that stars and stellar islands, although large, still have finite dimensions. We learn that the world space in which they all are is infinite. Every star, every star system once arose and will one day collapse. They exist, though for a very long time, but still finite time, the whole universe as a whole is infinite in time. This book does not outline all the issues of modern astronomy. But for those interested in astronomy, it could be