The Sun, the center of the Solar System is our star which is a huge ball of very hot gas. Its diameter is over 100 times more than the Earth’s diameter. Its surface is 60 times as hot as boiling water. The temperature at its center is around 15 million degrees C, and the heat flows outwards in all directions to the surface.

Sun gives us energy, warmth, and light. The Sun is a star. Our nearest star is the Sun. Sun is a very small star. Millions of other stars are much bigger than the Sun.

The coolest spot on the sun is the dark eye of a spot. Sunspots appear where bundles of magnetic field lines punch through the photosphere (the surface 5700 degrees C) and slow the rise of heat. Sunspot usually forms in pairs; the largest seen here can swallow the earth.

As you move away from the sun, the temperature begins to soar in a region called the chromosphere. This is visible from the earth as a thin red band. The temperature continues to climb in the sun’s outer atmosphere, the corona. Coronal heat likely comes from complex actions in magnetic field lines that rise above the surface. The temperature rises up to 2 million degrees C when there is an interaction of the sun’s magnetic fields and its electrified gases. These are studied with a satellite called TRACE.

The sun’s core is a thermonuclear reactor, fusing hydrogen into helium. Because of the intense heat, these gases exist in an electrified state of matter called plasma. It takes hundreds of thousands of years for the light to cross the dense interior to the convection zone, where plasma then bubbles to the surface.

All the nine planets including our earth move round and round the sun. The sun holds its family of the planets near it by the pull of gravity. Gravity is the force that attracts objects and makes things fall to the ground when you drop them. The sun, the earth and other planets with their moons all have their own gravity attracting with different strengths. The gravitational pull on the planets by each other and by the sun keeps them all where they are.

The Sun and its planets are called the Solar System. The word solar means belonging to the Sun. We could not live without the heat and light that the sun gives us.