Neutron Stars

- Describe the nature of neutron stars...
- Describe how astronomers obtain evidence for the existence of neutron stars...

A star between 4 and 25 solar masses will grow to a red super giant and explode as a supernova, leaving a neutron star smaller than the size of Earth.

These stars are compressed so much that they are composed entirely of neutrons, parts of the atom without electrical charge.

This is the equivalent of the size of the Sun in the same area as a city or the human population on Earth fitting inside an area the size of a sugar cube.

Neutron stars rotate rapidly after formation, typically spinning between fractions of a second and half a minute. We can detect this because they emit radio pulses, and the ones we detect are known as pulsars. Radio astronomy has also detected brightness and temperature from neutron stars, and astronomers have used x-ray astronomy to detect them when matter from companion stars falls onto neutron stars.


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Imagine the Universe Neutron Stars


  • Describe a neutron star
    - What are they composed of?
    - How do they 'act'?
  • What technques have scientists used to discover neutron stars?


Did you know?
There are over 2000 known neutron stars that have been discovered in our galaxy.