The Jacchia Reference Atmosphere is an atmospheric model that define 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. A common assumption while using the Jacchia Model is that the atmosphere rotates with the Earth as a rigid body.
Please compare the value of total mass density with newer models like MSISE series. I have improved some parts (i.e. computation of Sun's position) of the standard Jacchia 1970 model.
WARNING: Do not use.
Littered with bugs, poorly written, and poorly documented. Clearly the author did not apply any sort of academic or professional rigor to this implementation.
Average error vs. an industry standard J70 implementation is 70%. You're better off rolling your own.
Revised on 2018-01-20.