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Heavier elements were mostly produced much later, in stellar nucleosynthesis. Hydrogen and helium are estimated to make up roughly 74% and 24% of all baryonic matter in the universe respectively. Despite comprising only a very small fraction of the universe, the remaining "heavy elements" can greatly influence astronomical phenomena.
Carbon is the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. Marc Kuchner and Sara Seager coined the term "carbon planet" in 2005 and investigated such planets following the suggestion of Katharina Lodders that Jupiter formed from a carbon-rich core. [2]
The Earth's crust is one "reservoir" for measurements of abundance. A reservoir is any large body to be studied as unit, like the ocean, atmosphere, mantle or crust. Different reservoirs may have different relative amounts of each element due to different chemical or mechanical processes involved in the creation of the reservoir.
It has been estimated that the solid earth as a whole contains 730 ppm of carbon, with 2000 ppm in the core and 120 ppm in the combined mantle and crust. [56] Since the mass of the earth is 5.972 × 10 24 kg, this would imply 4360 million gigatonnes of carbon. This is much more than the amount of carbon in the oceans or atmosphere (below).
The idea that black holes could form in the early universe was first suggested by Yakov Zeldovich and Igor Dmitriyevich Novikov in 1967, and independently by Stephen Hawking in 1971. It quickly became clear that such black holes might account for at least part of dark matter.
It was believed that the cutoff for round objects is somewhere between 100 km and 200 km in radius if they have a large amount of ice in their makeup; [1] however, later studies revealed that icy satellites as large as Iapetus (1,470 kilometers in diameter) are not in hydrostatic equilibrium at this time, [2] and a 2019 assessment suggests that ...
Carbon-based photosynthesis life caused a rise in oxygen on Earth. This increase of oxygen helped plate tectonics form the first continents. [10] It is frequently assumed in astrobiology that if life exists elsewhere in the Universe, it will also be carbon-based. [11] [12] Critics, like Carl Sagan in 1973, refer to this assumption as carbon ...
Porous chondrite dust particle. Cosmic dust – also called extraterrestrial dust, space dust, or star dust – is dust that occurs in outer space or has fallen onto Earth. [1] [2] Most cosmic dust particles measure between a few molecules and 0.1 mm (100 μm), such as micrometeoroids (<30 μm) and meteoroids (>30 μm). [3]