Question

when was black hole formed?

Answer 1

When any star bursts then the back whole formed .

Answer 2

Black hole is formed when a massive star/planet dies and blasts out. The gases and the core of that star start spiraling around the place of the star creating and energy field along with a radiation spreading wide in a circular form. Due to vaccum the light is not produced by black hole and thus it remains dark. This is the formation of black hole.