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The mineral pyrite (/ ˈ p aɪ r aɪ t / PY-ryte), [6] or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S 2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral .
The Sun's atmosphere is composed of five layers: the photosphere, the chromosphere, the transition region, the corona, and the heliosphere. The coolest layer of the Sun is a temperature minimum region extending to about 500 km above the photosphere, and has a temperature of about 4,100 K. [77]
If the extraterrestrial solar radiation is 1,367 watts per square meter (the value when the Earth–Sun distance is 1 astronomical unit), then the direct sunlight at Earth's surface when the Sun is at the zenith is about 1,050 W/m 2, but the total amount (direct and indirect from the atmosphere) hitting the ground is around 1,120 W/m 2. [6]
When the concentration of oxygen molecules in the atmosphere reached 1% of the present level, the chemical reactions during weathering were much like they are today. Siderite and pyrite were replaced by the iron oxides magnetite and hematite; dissolved Fe 2+ ions that had been carried out to sea were now deposited in extensive banded iron ...
The atmosphere of Earth is composed of a layer of gas mixture that surrounds the Earth's planetary surface (both lands and oceans), known collectively as air, with variable quantities of suspended aerosols and particulates (which create weather features such as clouds and hazes), all retained by Earth's gravity.
The mineral marcasite, sometimes called "white iron pyrite", is iron sulfide (FeS 2) with orthorhombic crystal structure. It is physically and crystallographically distinct from pyrite, which is iron sulfide with cubic crystal structure. Both structures contain the disulfide S 2 2− ion, having a short bonding distance between the sulfur atoms.
Charged particles known as plasma create space weather that interacts with an upper layer of Earth’s atmosphere, called the ionosphere. The region acts as a boundary between Earth’s lower ...
The solar wind is a stream of plasma released from the Sun's upper atmosphere. It consists of mostly electrons and protons with energies usually between 1.5 and 10 keV. The stream of particles varies in density, temperature and speed over time and over solar longitude. These particles can escape the Sun's gravity because of their high energy.