Oxygen is essential for life on Earth, supporting every organism from the smallest microbes to the largest animals. However, space beyond Earth’s troposphere is a vacuum, devoid of oxygen. This raises a fascinating question: How does the sun shine so brightly in an environment without oxygen?
In classical terms ,we need oxygen to burn but the sun is not actually on fire. Its heat and light come from nuclear fusion reactions. This process doesn’t require oxygen to happen.
So, the burning of the sun is not a chemical combustion, it is a nuclear fusion. The sun is considered as the giant hydrogen bomb. In the nuclear fusion, the nuclei of the atoms fused with each other to form a larger nuclei.
Nuclear fusion produces much more energy than chemical reactions. In fusion, light atomic nuclei (like hydrogen) combine to form heavier nuclei (like helium), releasing tremendous amounts of energy. This is because the mass of the resulting nucleus is slightly less than the sum of the masses of the individual particles that fused. This “missing” mass is converted into energy.
For example, the fusion of hydrogen into helium in the Sun releases millions of times more energy per reaction than chemical processes like burning wood or fossil fuels. This is why stars, including our Sun, can shine for billions of years—nuclear fusion provides an incredibly efficient source of energy.
Hydrogen bomb is also based on fusion reactions. Energy released is so enormous that it is about 1000 times that of an atomic bomb. High temperatures of stars including the sun is due to fusion reactions.
Name: Dimple Shekhawat
Department: Chemistry Foundation
Narayana Jaipur Center (NIHQ)