Earth formed around 4.54 billion years ago, approximately one-third the age of the universe, by accretion from the solar nebula. Volcanic outgassing probably created the primordial atmosphere and then the ocean, but the early atmosphere contained almost no oxygen.

What was before Earth?

Life may have arisen in our solar system before Earth even finished forming. Planetesimals, the rocky building blocks of planets, likely had all the ingredients necessary for life as we know it way back at the dawn of the solar system, said Lindy Elkins-Tanton, a planetary scientist at Arizona State University (ASU).

When was the Earth formed?

Earth formed from debris orbiting around our sun about 4 ½ billion years ago. That is also the approximate age of the sun, but it is not the beginning of our story. The story really begins with the Big Bang nearly 14 billion years ago, which spewed hydrogen atoms throughout the universe.