The dominant theory of planetary nebula
-
The dominant theory of planetary nebula formation previously involved only a single star – the red giant itself. With only a weak gravitational hold on its outer layers, it sheds mass very rapidly near the end of its life, losing as much as 1% per century. It also churns like a boiling pot of water underneath the surface, causing the outer layers to pulse in and out. Astronomers theorised that these pulsations produce shock waves that blast gas and dust into space, creating what's called a stellar wind. Yet it takes a great deal of energy to expel this material completely without having it fall back into the star. It cannot be any gentle zephyr, this wind – it needs to have the strength of a rocket blast.
Keep reading : โรงเรียนบ้านสวนอาย
Content : ไต