Why doesn't the Sun blow up?

In fact, the Sun is doing a slow-motion explosion. It is shedding about 600 million tons every second in light energy, and it is loosing about 100 trillionth of its mass every year in the so-called solar wind. Here is a satellite photo of obne of these mass ejections seen by the SOHO satellite on December 2, 2003:

But the sun will never blow up the way we think of a genuine explosion. It is the wrong kind of star to be either a nova or a supernova.

The energy of the Sun, the thermonuclear fusion which produces all the heat and light, is occurring in the core of the Sun. The weight of all the mass in the Sun in the overlying layers is so enormous that the Sun is in an equilibrium state where the internal thermal pressure is balanced by the gravitational pressure directed inwards.


Return to Ask the Astronomer