“To be a star, you must shine your own light, follow your own path, and don’t worry about the darkness, for that is when the stars shine brightest”

Can you believe that the very reason for life on earth to exist is the violent death of a massive star? Death of a star leads to the birth of life somewhere far away in the galaxy.

First the basic facts.

Most of the universe is made of just the first two elements in the periodic table ie Hydrogen and Helium, which were created when the universe was initially born during the Big Bang. And when we say most of the universe we mean more than 98% of the universe is made up of only the first two chemical elements in the periodic table. Hydrogen makes up around 73% of the universe, while Helium accounts for 25% of the mass of the universe! All remaining 100 odd elements account for only 2% of the mass of this universe!

And yet we now find that earth is mostly filled with only these other elements and without which life cannot exist! From where did all these elements come from?

The only place where other elements can be created in the universe are at the cores of stars where Hydrogen and Helium fuse to create heavier elements. Again in normal stars like Sun this can go up only till the creation of Oxygen which is still only the 8th element in a periodic table which contains more than 100 chemical elements!

Where did the other more than 90 elements (ie more than 90% of the variety) which we see on this planet come from? Where were Aluminium, Iron, Gold, Silver, Uranium, Lead all created?

Well, this can happen only in the core of a star many times massive than the Sun. And even such massively massive stars can create only elements upto Iron at their core. Now this again means that only less than 25% of the known elements can be created at the core of stars no matter how massive they are. So where did all the remaining heavier 75% of the elements come from? Where were all these lead, gold, silver, uranium, plutonium, all created. Where did all the Iodine, Copper, Zinc, Cobalt, Copper in our body come from?

The answer is this can happen only when a massive star undergoes a supermassive explosion at the end of its life. The hot Iron core of a supermassive star finally is unable to withstand the gravitational pressure and causes the star to explode. It is such a massive explosion that the energy radiated out in this explosion is more than the total energy emitted by our star, the Sun during its entire life time. A Supernova explosion in a galaxy is brighter than the rest of the entire galaxy! The stellar remnants fly at 10% of the speed of light during this supernova explosion!

And it is at the heart of these supernova explosions that all the heavier 75% of the chemical elements we see in the periodic table get created. And one such explosion threw away all those elements that we see on earth today. The gold in your ornaments, the silver in the statues, the uranium in the nuclear reactors, the radium in the watches, the copper in the utensils, the lead in the batteries, the Iodine in the seas were all created during the violent death of a massive star.

Earth, life on earth, we humans all are made up of supernova explosions. Sun was probably created from the left over hydrogen and helium in that explosion. Most of the elements that make up the computer which you are using now to read this article, most of the solar system and also your body – were originally created in a supernova explosion.

Just imagine how massive that star would have been? Our Sun would be a dwarf in front of that star.

What would happen if a nearby massive star in our galaxy undergoes a supernova explosion? Wouldn’t it this time cause life on earth to be destroyed instead of getting created? In fact scientists observed the occurrence of a radio active isotope of Iron which would have arrived on Earth only from a nearby Supernova explosion which would have occurred sometime around 5 million years ago ie just before Humans evolved on this planet. Birth and Death dont they look like the two faces of the same coin? Death of a star leads to the birth of complex life form. Isn’t this amazing, which we otherwise rarely think about?

Who are we? We find that we live on an insignificant planet of a humdrum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people. – Carl Sagan