Latest Hadean Stories
The first 500 million years after the Earth formed is a period known as the Hadean. Until recently, it was believed that this time in Earth's history was hellacious. A new study reveals that this assumption may be false and that the early Earth may have been surprisingly similar to present day.
Over four billion years ago, giant asteroid impacts collided with the Earth’s surface and gave the planet a facelift of sorts – mixing, burying and melting the landscape, according to a new terrestrial bombardment model devised by an international team of researchers.
Researchers, publishing a paper in the journal Nature Geoscience, say a rock in Australia is helping to paint a picture of how our planet became habitable 4.4 billion years ago.
Just eight percent of the nearly 5,000 different types of minerals currently found on Earth were present on or near the planet’s surface when life first originated, according to new research appearing in the latest edition of the American Journal of Science.
Investigating the history of water on Earth is critical to understanding the planet's climate. One central question is whether Earth has always had the same amount of water on and surrounding it, the same so-called "water budget".
Scientists in the New York Center for Astrobiology at Rensselaer Polytechnic Institute have used the oldest minerals on Earth to reconstruct the atmospheric conditions present on Earth very soon after its birth.
Large bombardments of meteorites approximately four billion years ago could have helped to make the early Earth and Mars more habitable for life by modifying their atmospheres.
The bombardment of Earth nearly 4 billion years ago by asteroids as large as Kansas would not have had the firepower to extinguish potential early life on the planet and may even have given it a boost.
The argument over whether an outcrop of rock in South West Greenland contains the earliest known traces of life on Earth has been reignited, in a study to be published in the Journal of the Geological Society on 23 February.
The Archean (formerly Archaeozoic) is a geologic eon between the Hadean and Proterozoic eons. The Archean Eon begins at roughly 3.8 billion years ago (Ga) and ends at about 2.5 Ga. But unlike all other geological ages, which are based on stratigraphy, The Archean eon is defined chronometrically. The lower boundary of 3.8 Ga has also not been officially recognized by the International Commission on Stratigraphy. The name Archean is derived from the ancient Greek (Arkhe), meaning...
The Hadean is the unofficial geological period of time that lies just before the Archean time period. The Hadean began with the formation of the Earth roughly 4.5 billion years ago (Ga) and ended about 3.8 Ga; the latter date varies according to different sources. Hadean is derived from Hades, Greek for “underworld,” referring to the hellish conditions on the planet at the time. The term was coined in 1972 by geologist Preston Cloud. The period was later classified as the “Priscoan...
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