Surprising discovery shows a strong link between Earth's magnetic field and atmospheric oxygen levels
Every breath we take in contains 21% oxygen, the gas that makes life on Earth possible. Oxygen, in its combined oxide state, has always been abundant in Earth's crust, but elemental diatomic oxygen became part of our atmosphere around 2.4 to 2.5 billion years ago as a gift from cyanobacteria, which triggered the Great Oxidation Event and breathed life into Earth.
Every breath we take in contains 21% oxygen, the gas that makes life on Earth possible. Oxygen, in its combined oxide state, has always been abundant in Earth's crust, but elemental diatomic oxygen became part of our atmosphere around 2.4 to 2.5 billion years ago as a gift from cyanobacteria, which triggered the Great Oxidation Event and breathed life into Earth.
