A “teaspoon” of neutron-star matter is only a thought experiment
The claim that a teaspoon of neutron-star matter would have a mass on the order of a billion tons on Earth is a rough comparison meant to convey its extraordinary density. ESA estimates about a trillion kilograms. But such matter cannot literally be scooped up or safely transported: outside the star’s pressure, its state would change.
Illustration is AI-generated and conceptual; it does not depict a black hole’s interior.
The analogy does not work for a black hole. A black hole is not described as a lump of ordinary matter with a uniform density that could be measured by the spoonful. The event horizon is the black hole’s boundary; classical general relativity predicts a singularity at its center, which also signals the limits of the theory and the lack of a complete quantum-gravity description. Thus, “the weight of a teaspoon of a black hole” has no well-defined physical meaning.