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 What does this have to do with generating energy? If we put on a balance four hydrogen atoms and one helium atom, we see that the mass of the hydrogen atoms is slightly larger than the helium in 0.7 % or so. This means that during the fusion process of hydrogen atoms, part of the mass is lost!

DID YOU KNOW THAT…

''...the core of the Sun can reach 15 million Celsius degrees, and its pressure is 200 billion times higher than the atmospheric pressure on Earth? Only under these conditions, the fusion of lightweight elements can occur, transforming them into heavier ones.''

If you had heard that “the mass can neither be created nor destroyed” then, what happened with the mass loss on the fusion process? In this case, the energy is the one which transforms, and the mass is only a type of energy, such as light and heat. The famous formulae E=mc2, which reads “energy = mass times the speed of light squared,” precisely stands for this: if the mass of something is multiplied by the speed of light squared, it is obtained its rest energy.

If we want to or could transform 1 kg stone into energy, we would have to do it this way: E= mc2 Where c = 300 000 000 [m · s-1] (the speed of light in vacuum) m = 1 kg E= 1 x (300 000 000)2 [Kg · m2 · s-2] E= 9 x 1016 [Joules]

This energy is tremendous, similar to the total energy released by an earthquake magnitude 9.1 or half of the energy of the most powerful nuclear weapon ever detonated in human history: The Tsar Bomba.

The Sun has a luminosity of 3.8x10 26 J/s. If we divide this value by the speed of light squared, we obtain the mass that the Sun turns into energy at every second. It is more than four million tons of matter. Fortunately, as our star has so much mass, we can say that it can withstand those levels of energy production for at least 4.5 billion years more.

If it has lived that amount of years already, we might say that it is in the middle of its age as it is estimated that it will live about 9 or 10 billion years.

DID YOU KNOW THAT…

...the energy that the Sun produces takes at least 100,000 years to come out of it and reaches the Earth in only eight minutes?

DID YOU KNOW THAT…

at every second, the Sun produces more energy than all humanity has spent in its history? • • • 25