When a massive star dies, it can leave behind an object so dense that a sugar-cube-sized piece would weigh as much as a mountain: a neutron star. Some spin hundreds of times a second and sweep the sky with beams of radiation like cosmic lighthouses. This episode explores the most extreme form of matter we know of, short only of a black hole.

You'll come away understanding how neutron stars form, just how unimaginably dense they are, what a pulsar is, and how colliding neutron stars forge the gold and platinum in the universe.

Talking Science is sponsored by Kinsoft. Visit www.kinsoft.com.au

Further reading: NASA – "Neutron Stars"; Jodrell Bank Observatory – pulsar resources; LIGO/Virgo – neutron star mergers.