Space
How much would a teaspoon of neutron star weigh?
A teaspoon of neutron star material would weigh around a billion tonnes.
Source: Density about 5 × 10¹⁷ kg/m³; Science News (2017).
Context
Around a billion tonnes. Neutron star material has a density of about 5 × 10¹⁷ kg per cubic metre, because it is essentially atomic nuclei packed together with no empty space between them.
A neutron star packs more than the Sun's mass into a sphere about the width of a city. The teaspoon would not stay a teaspoon away from the star; it is the star's gravity that holds matter that dense.
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