pulsar

Everyday

A tiny, very heavy, spinning dead star (a neutron star) that sends out beams of radio waves or light, which reach Earth as very regular pulses, like a lighthouse. tree →

In the lessons

In science and space lessons pulsars come up when talking about what happens after a giant star explodes in a supernova. Their pulses are so regular that scientists use them like cosmic clocks. The first pulsar was discovered by Jocelyn Bell Burnell, a student from Northern Ireland.

Examples

• A pulsar spins hundreds of times a second. tree →
• The pulsar's beam sweeps past Earth like a lighthouse. tree →
• Jocelyn Bell Burnell discovered the first pulsar. tree →
• At first scientists jokingly called the signal "little green men". tree →
• Pulsars are left over after a supernova. tree →
• Some pulsars keep time better than clocks on Earth. tree →

Note

Countable: a pulsar, pulsars. Comes from "pulsating star". Not the same as a quasar (a very bright centre of a faraway galaxy). A teaspoon of pulsar material would weigh millions of tonnes.