Life on Earth is totally dependent on the the energy it receives from the Sun. This energy is produced when hydrogen atoms inside the Sun fuse to form helium. The Sun consumes four million tons of hydrogen every second. Even so, it's so vast that our star has enough fuel to keep it shining for another five billion years. The Sun's energy output is estimated to be 386 billion, billion megawatts. So in 15 minutes our Sun radiates as much energy as mankind consumes in all forms, during an entire year. The Sun is by far the brightest object in the sky. It's so bright that during the day its light drowns out virtually everything else in space. The Sun is so powerful that even from the Earth, its light can damage your eyesight. So never look at the Sun directly or through a telescope. The best time to appreciate the majesty of the Sun from the Earth is during a solar eclipse. Then the Moon passes in front of the Sun and so it temporarily disappears from the sky.