A teaspoon of neutron star would weigh about as much as a mountain

Neutron stars pack more than the mass of the Sun into a ball roughly the size of a city. Their matter is so dense that a sugar-cube sample would weigh around a billion tonnes.

Neutron stars pack more than the mass of the Sun into a ball roughly the size of a city. Their matter is so dense that a sugar-cube sample would weigh around a billion tonnes.