2021-8-31 · Therefore, 5 ml of such material is 5.5 × 1012 kg, or 5 500 000 000 metric tons. This is about 15 times the total mass of the human world population. Alternatively, 5 ml from a neutron star of radius 20 km radius (average density 8.35 × 1010 kg cm−3) has a mass of about 400 million metric tons, or about the mass of all humans.