BEAUTIFUL BURSTS

1

Fusion

Stars generate energy through nuclear fusion. In massive stars it is via the carbon, nitrogen, oxygen (CNO) cycle, which act as catalysts for fusion involving hydrogen atoms.

2

Onion layers

Nuclear fusion of hydrogen creates helium. Temperatures grow so high that the helium begins to fuse to create oxygen, then nitrogen, carbon, silicon and so on.

3

Living fast

Massive stars struggle to stay aloft against the pull of gravity, so they have to generate a lot of energy, which uses up their vast stores of gas in just a few million years.

4

Iron star

Massive stars end up with cores of iron, which cannot undergo further nuclear fusion without putting in more energy than it produces. Fusion ceases in the star’s core.

5

Collapse

As the massive star reaches the end of its life and is unable to generate any more energy, the core of the star begins to collapse in on itself to form a black hole.

6

Jets

Gas inside the star swirls around the black hole and forms powerful jets that destroy it. Charged particles spiralling around the magnetic jets produce gamma rays.