"And may I remind you of something I wrote in 1968, which is even more pertinent today. We need books such as this to  remind us not only of the advances we have made, but of what we could be missing. . . "

"The challenge of the great spaces between the worlds is a stupendous one, but if we fail to meet it, the story of our race will be drawing to a close.  Humanity will have turned its back upon the still untrodden heights and will be descending again the long slope that stretches, across a thousand million years of time, down to the shores of the primæval sea."

Sir Arthur C. Clarke

Without the Hubble Space Telescope we would not be aware of amazing celestial sights like Eta Carinae, a star which exploded 150 years ago, blowing off its outer layers and forming an expanding nebula in the form of two billowing polar clouds. It is as bright as 5 million Suns, and will eventually become a supernova and then a neutron star.

The view from a planet revolving around a pulsar, such as PSR 1257+12. When in its most active phase, the radiation from the pulsar would render the surface red-hot, though later it would become very cold. The sky is filled with shells of fluorescing gas, caught in whirling magnetic fields, as seen in the Crab Nebula.

It is now known that collisions between galaxies are quite common, despite the immensity of space. This will even occur between our own Milky Way and its neighbour, M31 in Andromeda ~ though not for about three billion years. The result is usually an elliptical galaxy, often with a strange 'tail. Here two galaxies are just beginning to pass through each other.