Jacchia Reference Atmosphere

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The Jacchia Reference Atmosphere is a reference atmospheric model that defines values for atmospheric temperature, density, pressure and other properties at altitudes from 90 to 2500 km. Unlike the more common US Standard Atmosphere and related models, the Jacchia model includes latitudinal, seasonal, geomagnetic, and solar effects, but must be supplemented with another model at lower altitudes. The model, first published in 1970 and updated in 1971 and 1977, is based on spacecraft drag data, and is primarily used in spacecraft modeling and related fields.

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A common assumption while using the Jacchia Model is that the atmosphere rotates with the Earth as a rigid body.

The statistical accuracy of the Jacchia Model is 15%.

See also

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International Standard Atmosphere Atmospheric model

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In astronomy, air mass or airmass is a measure of the amount of air along the line of sight when observing a star or other celestial source from below Earth's atmosphere. It is formulated as the integral of air density along the light ray.

NRLMSISE-00

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Density altitude

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Atmospheric refraction

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U.S. Standard Atmosphere

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A reference atmospheric model describes how the ideal gas properties of an atmosphere change, primarily as a function of altitude, and sometimes also as a function of latitude, day of year, etc. A static atmospheric model has a more limited domain, excluding time. A standard atmosphere is defined by the World Meteorological Organization as "a hypothetical vertical distribution of atmospheric temperature, pressure and density which, by international agreement, is roughly representative of year-round, midlatitude conditions."

Explorer 9 NASA satellite of the Explorer program

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Explorer 24 NASA satellite of the Explorer program

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