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As Earth cooled, an atmosphere formed mainly from gases spewed from volcanoes. It included hydrogen sulfide, methane, and ten to 200 times as much carbon dioxide as today’s atmosphere. After about half a billion years, Earth’s surface cooled and solidified enough for water to collect on it.
- My How You've Changed
In the 4.6 billion years of Earth’s history, the composition...
- Modern Atmospheres
Since the Eocene is so recent (geologically speaking), many...
- The Archean Eon
The Archean Eon - The Earliest Atmosphere - Smithsonian...
- The Age of Oxygen
The Age of Oxygen - The Earliest Atmosphere - Smithsonian...
- Oxygen at Last
Oxygen at Last - The Earliest Atmosphere - Smithsonian...
- Oxygen Boom
Between 700-550 million years ago, in the late Proterozoic,...
- What Happens to Your Lunch
What Happens to Your Lunch - The Earliest Atmosphere -...
- Atmosphere Protects
The stratospheric ozone layer—the part of the atmosphere...
- My How You've Changed
27 Απρ 2021 · Research partly conducted at the Advanced Photon Source helped scientists discover the composition of Earth’s first atmosphere. What they found raises questions about the origin of life on Earth.
12 Φεβ 1993 · Ideas about atmospheric composition and climate on the early Earth have evolved considerably over the last 30 years, but many uncertainties still remain. It is generally agreed that the atmosphere contained little or no free oxygen initially and that oxygen concentrations increased markedly near 2.0 billion years ago, but the precise timing of ...
Visconti (1975) computed the temperature of Earth’s upper atmosphere if the lower atmosphere were anoxic. He obtained thermospheric temperatures well over 1000 K for current solar max EUV fluxes.
7 Σεπ 2006 · temperature or isotopic composition. It is theoretically possible that the early Earth could have been hot. Climate calculations by Kasting & Ackerman (1986) showed that a dense greenhouse atmosphere containing 10 bars of C02 could have produced a mean surface temperature of approximately 80?C at 4.5 Ga, despite a 30% lower solar luminosity at ...
5 Αυγ 2008 · Earth's earliest atmosphere was the product of late-accretionary and internal heat-driven processes acting on late-accreting material mixed with the outer (fairly hot) parts of the Earth. Fifty percent or more of Earth's volatiles may have been degassed during this earliest phase of Earth history, probably before 4.2 Ga.
20 Δεκ 2002 · The hazy color of Titan's atmosphere may originate from large organic molecules formed by photochemical processes, despite surface temperatures far below the melting point of water.
