I just read an article about scientists pushing back origins of Earth's oxygen.
Did the oxygen actually begin to rise about 2.5 billion years ago? The scientists are finding some evidence from some rocks that the activity occured 50 to 100 million years before the Oxygen Catastrophe (known as the Great Oxidation Event).
For about the first half of the planet's existence, the environment had nearly no oxygen. I am curious to know how the planet acquire the oxygen after the atmosphere started to become thicker. Did part of oxygen get trapped inside the planet during its birth?
Like living things, oxygen and other gases have evolved for billions of years.