The Universe is a zoo inhabited by exotic creatures. The celestial menagerie reveals the creativity of physical forces: forces that astrophysicists untiringly try to explain by theory, experiment and observation.

In the 1930s, researchers like Lev Landau, Robert Oppenheimer, George Volkoff, Fritz Zwicky and Walter Baade, having gone through the calculations, became convinced of the theoretical existence of a star never hitherto observed. It was an extremely dense star, the core of which was just an aggregate of neutrons. Does it really exist? This question was asked for nearly thirty years until thanks to the observations of a young Irishwoman it was possible to confirm the theory. But what that theory could never have predicted was that one day a Polish researcher, employed by an American university and working on a radio telescope in Puerto Rico, would discover the first exoplanets around one of these dizzying stars.

PULSAR, YOU SAID A PULSAR?

At the age of eleven Susan Jocelyn Bell failed the entrance exam that would have enabled her to attend a state grammar school. However, her father, an architect who was curious about everything and astronomy in particular, instead sent her to a private school, where she thrived. Perhaps she owed her success there to her physics teacher, whose enthusiasm for the subject was matched by an ability to explain it. Whatever the reason, Susan developed a passion for her chosen subject that was to lead to one of the major astronomical discoveries of the twentieth century.