Timing of Optical Pulses from the Crab Nebula Pulsar

Timing the arrival of optical pulses from NP 0532 is a potentially important tool for studying the physics of this fascinating object. However, there are some difficulties in interpreting the data in terms of physical models. Some progress has been made on understanding the largest effect — the pulsar braking mechanism. The glitch of late September, 1969 can be interpreted as the speed-up, and subsequent relaxation, of the rotation of a neutron star crust. An alternate explanation is that of a planet in an eccentric orbit. Both models fit the rather meager data near the event. A small sinusoidal effect is indicated in a relatively quiet period of the data.