What is formed when the remaining core of a high-mass star is too massive for a neutron star to support?
Answer
Black hole
If the remaining core of a star after a supernova is extremely massive, it collapses indefinitely because the density of a neutron star is not sufficient to counteract the inward gravitational pull. This creates a black hole, a region of space where gravity is so intense that nothing can escape its grasp, not even light itself.

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