The expanding shell of gas and dust from an exploded star glows in different wavelengths of energy in this composite image from three telescopes. The supernova remnant, known as E0102-72, is about 170,000 light-years away in the Small Magellanic Cloud, a small companion galaxy to the Milky Way. The outer shell, in red, shows the remnant's radio waves, which are produced as the expanding shell rams into slower-moving material around it. The blue, representing X-rays, shows that the remnant contains large amounts of oxygen and carbon -- elements that are essential for life. These elements were forged in the heart of the star, and may now be incorporated into future stars, planets, or even living beings. The green streamers show the remnant in optical wavelengths, so the eye alone would see only these structures (though not in green). [NASA/CXC/SAO/HST/ACTA]
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
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