Neutron star

Definition

A neutron star is a highly dense remnant of a massive star that has undergone a supernova explosion and collapsed under gravity. Composed mostly of neutrons, it exhibits incredibly strong gravitational and magnetic fields.

5 Must Know Facts For Your Next Test

1. Neutron stars have masses between 1.4 and 3 times that of the Sun but radii of only about 10 kilometers.
2. The immense gravitational field of a neutron star means that its escape velocity is close to half the speed of light.
3. Neutron stars can spin rapidly, with some rotating several hundred times per second, known as pulsars.
4. The strong magnetic fields of neutron stars can be trillions of times stronger than Earth's magnetic field.
5. General Relativity predicts significant spacetime curvature around neutron stars, leading to phenomena such as gravitational lensing.

Review Questions

• What is the typical mass range for a neutron star?
• How does General Relativity describe the spacetime around a neutron star?
• Why are some neutron stars referred to as pulsars?

Related terms

Supernova: A powerful and luminous stellar explosion marking the end of a massive star's life cycle, often leading to the formation of neutron stars or black holes.

Pulsar: A type of rapidly rotating neutron star that emits beams of electromagnetic radiation out of its magnetic poles, observable as pulses when they sweep past Earth.

Gravitational Lensing: $\text{Einstein's}$ theory predicts that mass curves spacetime; thus, light passing near a massive object like a neutron star will bend, creating phenomena such as multiple images or magnification.