Luckily for us, oxygen is one of the most abundant elements on Earth. It's in the air, the water, and the rocks beneath our feet. But the amount of oxygen on Earth is tiny compared to the amount created by an exploding star in the Small Magellanic Cloud, a companion galaxy to the Milky Way. It manufactured a hundred thousand times more oxygen than is found not just on Earth, but in our entire solar system.
The star manufactured the oxygen and many other elements in its core. It began life as a big ball of hydrogen and helium. Nuclear reactions in the core converted these elements into progressively heavier ones, producing energy in the process. Once the core was converted to iron, it could no longer produce energy, so the core collapsed and the star's outer layers exploded.
The explosion created a giant cloud that's expanding into space at thousands of miles per second. Observations by space-based X-ray telescopes showed that the cloud is rich in several elements, including oxygen.
Over the ages, some of the cloud's material will mix with other clouds. Perhaps triggered by the exploding star itself, these clouds will collapse and give birth to new stars and planets. It's a process that's played out countless times before -- including in our own solar system. That means that the oxygen in our air and water was forged in the heart of a star that long ago blew itself to bits, spreading life-giving elements through the galaxy.
Script by Damond Benningfield, Copyright 2010