Stage 1 – Massive stars evolve in a similar way to a small star until it reaches its main sequence stage (see small stars, stages 1-4). The stars shine steadily until the hydrogen has fused to form helium ( it takes billions of years in a small star, but only millions in a massive star).
Stage 2 – The massive star then becomes a Red Supergiant and starts of with a helium core surrounded by a shell of cooling, expanding gas.
Stage 4 – The core collapses in less than a second, causing an explosion called a Supernova, in which a shock wave blows off the outer layers of the star. (The actual supernova shines brighter than the entire galaxy for a short time).
the tag called Supernova and contracting to become a neutron star
age 5 – Sometimes the core survives the explosion. If the surviving core is between 1.5 – 3 solar masses it contracts to become a tiny, very dense Neutron Star. If the core is much greater than 3 solar masses, the core contracts to become a Black Hole.
If you want to find out more about Messier objects then there is a good link to start you off.