ABSTRACT
At the centre of our sun, the extreme temperature of 10 to 20 million degrees causes protons to crash into one another, so converting some of their mass to energy. A cascade of reactions then produces energy-rich gamma photons, each of which eventually divides into a thousand photons during the several million years they take to reach the sun's surface. These photons then depart the sun at 300,000 kilometres a second and take about eight and a half minutes to travel the 154 million kilometres to our planet, the third nearest to the sun.
