Astronomy Chapter 15 Summary

When a star dies, it can become a?

White dwarf, neutron star, or black hole.

When does a white dwarf form?

A low mass star expels its outer layers to form a planetary nebula shell and leaves its hot core exposed.

What is the approximate radius of a white dwarf?

About the same as the Earth’s.

What must the mass of a white dwarf be less than?

The Chandrasekhar limit, or it will collapse.

What may happen if a white dwarf is in a binary system?

It may accrete mass from its neighbor and explode either as a nova or as a type Ia supernova.

How does a neutron star form?

When a massive star’s iron core collapses and triggers a supernova explosion.

What happens to the core during the formation of a neutron star?

The core’s protons and electrons are compressed to make neutrons.

What do a neutron star's spinning and magnetic field generate?

Beams of radiation that sweep across space, making the spinning neutron star a pulsar.

What is formed when a massive star’s iron core contains more than about 3 M?

A black hole.