Emerald Robinson: Hi! I am emerald Robinson. In this What is? video, we're going to take a closer look at supernovas.
A supernova is a massive explosion generated by dying star. A star in our galaxy goes supernova approximately, once every 100 years. The explosion hurls matter in the space and can shine as brightly as an entire galaxy, for short periods.
Stars are giant nuclear reactors, producing energy by fusing hydrogen into helium. Eventually however, stars run out of hydrogen to fuse, when this occurs the star fuses healing into heavier elements, including iron. The stars course shrinks while it's outer layers expand.
Creating a red giant that consumes surrounding planets. What happens when the sun runs out of helium? Fusion simply ends in small stars like our Sun. The stars becomes a white dwarf and slowly fades away. When a large star depletes it's helium reserve the core collapses within second, causing temperatures an excess of 100 billion degree.
The outer layers of the star collapse as well only to explode outwards in a massive explosion known at a supernova. Supernova generate enough energy to fuse elements heavier than iron, gold, silver, uranium, and other elements with high atomic numbers are created in supernovas.
What's left at the stars core becomes a dense neutron star or forms a black hole. An area of such densely packed matter that not even light escape it's gravitational pull. After a supernova material expelled in the explosion may form nebulae. Massive interstellar clouds of gas and dust.
Over millions of years gravity pulls nebulae material together into a dense hot core called a proto star. Proto stars eventually become new born stars. The new stars gravitation affects surrounding nebula material, which may form comets, asteroids, and new planet. It's truly the solar circle of life.