Massive Stars (Important Facts) {Part-9}

MASSIVE STARS HAVE A MASS AT LEAST THREE TIMES that of the Sun, and some stars are as massive as about 50 Suns. A massive star evolves in a similar way to a small star until it reaches the main sequence stage. During its life as a main sequence star, it shines steadily until the hydrogen

Massive Star

in its core has fused to form helium. This process takes billions of years in a small star, but only millions of years in a massive star. A massive star then becomes a Red Supergiant, which initially consists of a helium core surrounded by outer layers of cooling, expanding gas. Over the next few million years, a series of nuclear reactions from different elements in shells around as iron core. The core eventually collapses in less than a second, causing massive explosion called a Supernova.

Supernova

in which a shock wave blows away the outer layers of the star. Supernova shine brighter than a star.
Supernovae shine brighter than an entire galaxy for a short time. Sometimes, the core survives the supernova explosion. If the surviving core is between about one and a half and three solar masses, it contracts to become a tiny, dense Neutron Star. If the core is greater than three solar masses, it contracts to become a Black Hole.

Neutron Star

Black Hole