The tour starts close to home within the first domain, our own solar system. There is a tremendous variety here, from the sun scorched rocks of Mercury to the icy vastness of the Kuiper Belt beyond Pluto. We see the sun and planets born from the collapse of an interstellar dust cloud whose atoms were themselves created in long dead stars. Since many of these planets have been visited by space probes or landers, we are able to benefit from the incredible technology of exploration developed by NASA and its counterparts in other countries. The second domain is made up of the billions of stars in our own Milky Way galaxy. We walk in the steps of the American astronomer Edwin Hubble, who first established that the universe is made up of discrete galaxies, then go on to examine the fundamental constituents of those galaxies-the stars. We see stars not as eternal lights in the sky, but as objects born out of a desperate struggle between pressure and gravity. We trace the life cycle of our own sun, from its birth 4.5 billion years ago to its quiet end 6 billion years in the future. We see the galaxy not as a serene and placid place, but as a giant factory, where primordial material is ta