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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.
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.
The age of Earth is about 4.54 billion years; [7] [33] [34] the earliest undisputed evidence of life on Earth dates from at least 3.5 billion years ago according to the stromatolite record. [35] Some computer models suggest life began as early as 4.5 billion years ago. [36] [37] The oldest evidence of life is indirect in the form of isotopic ...
Visual representation of the Logarithmic timeline in the scale of the universe. This timeline shows the whole history of the universe, the Earth, and mankind in one table. . Each row is defined in years ago, that is, years before the present date, with the earliest times at the top of the ch
According to evidence from radiometric dating and other sources, Earth formed about 4.54 billion years ago. [7] [8] [9] The current dominant theory of planet formation suggests that planets such as Earth form in about 50 to 100 million years but more recently proposed alternative processes and timescales have stimulated ongoing debate in the planetary science community. [10]
The rise in oxygen is attributed to photosynthesis by cyanobacteria, which are thought to have evolved as early as 3.5 billion years ago. [ 18 ] The current scientific understanding of when and how the Earth's atmosphere changed from a weakly reducing to a strongly oxidizing atmosphere largely began with the work of the American geologist ...
During the first billion years of Earth's history, the ocean formed and then life developed within it. Life spread globally and has been altering Earth's atmosphere and surface, leading to the Great Oxidation Event two billion years ago. Humans emerged 300,000 years ago in Africa and have spread
Holmes published The Age of the Earth, an Introduction to Geological Ideas in 1927 in which he presented a range of 1.6 to 3.0 billion years increasing the estimate in the 1940s to 4,500 ± 100 million years, based on measurements of the relative abundance of uranium isotopes established by Alfred O. C. Nier. Theories that did not comply with ...