A neutron star can have up to twice the mass of the Sun, but will be only about 20 kilometres in diameter. A matchbox full of neutron star material would weigh the same as Wales; a house full of it would weigh the same as the Moon.
(How much does Wales weigh? Surely it would depend on how deep you dug before scooping it out. But you get the point.)
© Haydn Thompson 2017