A supernova remnant is the structure resulting from the explosion of a star in a supernova. There are two possible routes to a supernova: either a massive star may run out of fuel, ceasing to generate fusion energy in its core, and collapsing inward under the force of its own gravity to form a neutron star or a black hole; or a white dwarf star may accumulate material from a companion star until it reaches a critical mass and undergoes a thermonuclear explosion. One of the best observed young supernova remnants was formed by SN 1987A a supernova in the Large Magellanic Cloud that was observed in February 1987. Other well-known supernova remnants include the Crab Nebula.
A Supernova Remnant goes through these phases:
1. Free expansion of the ejecta 2. Sweeping up of a shell of shocked circumstellar and interstellar gas
3. Cooling of the Shell 4. Cooling of the interior
5. Merging with the surrounding interstellar medium
There are various types of Supernova Remnants including:
-Shell like, such as Cassiopeia A
-Composite, in which a shell contains a central pulsar wind nebula, such as G11.2-0.3 or G21.5-0.9
-Mixed-morphology
No comments:
Post a Comment