‘What makes pulsars tick?’

Abstract

The late astronomer David Allen once described in his beautiful style the most remarkable feature of pulsars: how fast they spin. Imagine, he once said, that you were looking at a pulsar spinning on a pedestal. Paint a mark on the side of the pulsar near its equator. Now ask yourself: how fast would I have to drive in a car to keep up with that mark if the pulsar was spinning once a minute? Given a diameter of 20 km or so, you would in fact have to drive at a speed of around 3,700 kilometers an hour. However, pulsars do not spin once a minute, he went on. The first ones discovered spin in just a few seconds and it would not be long before even faster ones were found. It is no wonder that astronomers found such a concept difficult to accept, and for a long time the idea of pulsars being a spinning phenomenon was not taken seriously at all. No, there had to be another explanation.