It took another 2 to 3 billion years for enough atmospheric carbon dioxide to become trapped in the rocks and used by plants to make oxygen, leading to the development of a new, nitrogen- and oxygen-rich atmosphere. As ozone formed, blocking out ultraviolet rays from the Sun, more complex organisms started to evolve.
|When you are on Earth…|
…gravity keeps you on the ground;
…oxygen in the atmosphere enables you to breathe;
…the Sun keeps you warm in the daytime;
…you can see changes in atmospheric composition and pressure in the form of cloud movements, rainfall and lightning;
…you can observe interactions between solar particles and Earth’s magnetic field by watching an aurora borealis such as the Northern Lights;
…you can look out through Earth’s atmosphere to see the stars in the night sky.