Pulsars

Spinning neutron-star lighthouses whose radio ticks rival atomic clocks — found by a graduate student.

Core Principles & Analysis

• Jocelyn Bell Burnell spotted the first in 1967; the mock label "LGM-1" nodded to little green men.
• Millisecond pulsars keep time so well they are used to hunt gravitational waves across the galaxy.
• The Hulse-Taylor binary pulsar’s orbital decay gave the first proof of gravitational radiation.