Search results
Results from the WOW.Com Content Network
Earth formed in this manner about 4.54 billion years ago (with an uncertainty of 1%) [25] [26] [4] and was largely completed within 10–20 million years. [27] In June 2023, scientists reported evidence that the planet Earth may have formed in just three million years, much faster than the 10−100 million years thought earlier.
Altogether, the concordance of age dates of both the earliest terrestrial lead reservoirs and all other reservoirs within the Solar System found to date are used to support the fact that Earth and the rest of the Solar System formed at around 4.53 to 4.58 billion years ago.
Astronomers think the collision between Earth and Theia happened at about 4.4 to 4.45 billion years ago ; about 0.1 billion years after the Solar System began to form. [15] [16] In astronomical terms, the impact would have been of moderate velocity. Theia is thought to have struck Earth at an oblique angle when
Large and numerous impact craters can be recognised on planetary bodies across the Solar System. These craters are thought to date back to a period where there was an increased frequency and intensity of asteroid impacts with terrestrial planets, known as the Late Heavy Bombardment, which terminated approximately 4 billion years ago. [9]
Plate tectonics (from Latin tectonicus, from Ancient Greek τεκτονικός (tektonikós) 'pertaining to building') is the scientific theory that Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago.
The widely accepted giant impact hypothesis states that the Moon was created as a result of a catastrophic impact between Earth and another planet, resulting in a re-accumulation of fragments at an initial distance of 3.8 R 🜨 (24,000 km or 15,000 mi). [34] This theory assumes the initial impact to have occurred 4.5 billion years ago. [35]
The average age of Earth's current continental crust has been estimated to be about 2.0 billion years. [20] Most crustal rocks formed before 2.5 billion years ago are located in cratons . Such an old continental crust and the underlying mantle asthenosphere are less dense than elsewhere on Earth and so are not readily destroyed by subduction.
In 2017, fossilized microorganisms, or microfossils, were discovered in hydrothermal vent precipitates in the Nuvvuagittuq Belt of Quebec, Canada that may be as old as 4.28 billion years old, the oldest record of life on Earth, suggesting "an almost instantaneous emergence of life" (in a geological time-scale), after ocean formation 4.41 ...