What is the density of a neutron star?
A neutron star is so dense that one teaspoon of its material would have a mass over 5,500,000,000 tonnes (5.5 billion), about 900 times the mass of the Great Pyramid of Giza (often cited as 5.9 million tons / 5.3 million tonnes). At the extraordinarily high densities of neutron stars, ordinary matter is squeezed to nuclear densities. All of that matter is packed into a radius on the order of 10 kilometers (6 miles). Bonus fact: There are a number of sub-types of neutron stars, such as pulsars, magnetars, both pulsars and magnetars, x-ray pulsars, and more.
