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  2. Earth formed around 4.54 billion years ago, approximately one-third the age of the universe, by accretion from the solar nebula. [4][5][6] Volcanic outgassing probably created the primordial atmosphere and then the ocean, but the early atmosphere contained almost no oxygen.

  3. Oct 19, 2023 · At its beginning, Earth was unrecognizable from its modern form. At first, it was extremely hot, to the point that the planet likely consisted almost entirely of molten magma. Over the course of a few hundred million years, the planet began to cool and oceans of liquid water formed.

    • What Is The CORE Accretion Model?
    • What Is The Disk Instability Model?
    • What Is Pebble Accretion?
    • Additional Resources

    Approximately 4.6 billion years ago, our solar system was just a cloud of dust and gas known as a solar nebula. Gravitycollapsed the material in on itself as it began to spin, condensing the matter and forming the sun in the center of the nebula. With the sun beginning to form, the remaining material started to clump up. Small particles drew togeth...

    While the core accretion model works for terrestrial planets, gas giants would need to evolve rapidly to grab hold of the significant mass of lighter gases they contain. But simulations with that model have not been able to account for this rapid formation. In those simulations, the process takes several million years, which is longer than light ga...

    The disk instability model contends with the core accretion model's issue with time; specifically how quickly massive gas giants would have to grab lighter components. But another, recent model known as pebble accretion, also helps to fill in this explanatory gap. In this model, researchers have shown how smaller, pebble-sized objects could have fu...

    Visit NASA's hubfor understanding Earth as a planet.
    Explore NASA's kid-friendly resourcesfor learning about Earth.
    Browse NASA's hubfor understanding exoplanets.
    • Birth of the Sky. Early Earth was a hellscape of molten lava and barren rock, bombarded by meteors, with no atmosphere at all. How did our familiar blue sky – the thin, life-giving band of gasses protecting our planet – come to be?
    • Frozen Planet. 700 million years ago, Earth was a giant snowball cloaked in ice from pole to pole. How did life manage to hold on through this deadly deep freeze, find creative ways to bounce back, and thrive in the dramatically different world that emerged?
    • Life Rising. For billions of years, life teemed in Earth’s oceans while the land was desolate and inhospitable. See how life made the leap to land, transforming a barren, rocky landscape into the lush, green world we call home.
    • Inferno. 252 million years ago, a devastating mass extinction wiped out about 90% of all species on Earth. Follow scientists as they piece together evidence to discover how life survived and set the stage for a new dominant life form: the dinosaurs.
  4. en.wikipedia.org › wiki › EarthEarth - Wikipedia

    Earth, like most other bodies in the Solar System, formed 4.5 billion years ago from gas and dust in the early Solar System. During the first billion years of Earth's history, the ocean formed and then life developed within it.

  5. How and when did the early Earth form? Scientists now think the Earth’s story began around 4.6 billion years ago in a disk-shaped cloud of dust and gas rotating around the early sun, made up of material left behind after the sun’s formation.

  6. Sep 22, 2014 · Scientists believe Earth formed in this way about 4.6 billion years ago. Early in the process of its formation, a planetesimal the size of Mars hit Earth, knocking a big chunk of Earth into space. Scientists believe that chunk started its own orbit around Earth, becoming our Moon.

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