19/09/2026
Neutron stars are some of the strangest objects in the universe.
They’re not especially large. In fact, a typical neutron star is only around the size of a city. But inside that tiny object is an incredible amount of mass, packed together so tightly that the density becomes almost impossible to imagine.
So how does that happen?
It starts when a massive star reaches the end of its life and its core collapses. Under that extreme pressure, the space inside atoms is crushed down, and electrons and protons are forced together, forming neutrons.
Now all of that matter is packed into a ridiculously small space.
That’s why a neutron star can contain more mass than the Sun while being only around 20 kilometers wide.
And the density gets even crazier.
A teaspoon of neutron-star material would weigh around a billion tons on Earth.
In this Short, we break down why neutron stars are so heavy, how they form, and what makes them one of the most extreme objects in space.
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