black holes

A black hole is an area in space where gravity is so strong that nothing, not even light can escape from it. It forms when a massive star dies and its core collapses in on itself. The boundary of a black hole is called the event horizon, and any matter that passes this boundary will be pulled into the black hole. The mass of a black hole can range from a few times the mass of the sun to millions of times the mass of the sun. One example of a black hole is Cygnus X-1, located in the constellation Cygnus. It has 15 times the mass of our sun. Fun fact: Black holes can actually emit radiation, called Hawking Radiation, named after Stephen Hawking. This radiation is believed to be generated near the event horizon of a black hole and is thought to be responsible for the slow reduction in the mass and energy of a black hole.