Patent ID: 7345286

Claim:
A method comprising: detecting a first intensity of 83.4 nm airglow from singly charged oxygen ions (O + ) along a vector from Earth to a satellite above the ionosphere; obtaining a first altitude at which the number density of singly charged oxygen ions (O + ) peaks in the F-region of the ionosphere along the vector from Earth to the satellite; obtaining a first peak singly charged oxygen ion (O + ) number density in the F-region of the ionosphere along the vector from Earth to the satellite; obtaining a first atomic oxygen scale height in the F-region of the ionosphere along the vector from Earth to the satellite; estimating a second altitude at which the number density of singly charged oxygen ions (O + ) peaks in the F-region of the ionosphere along the vector from Earth to the satellite; estimating a second peak singly charged oxygen ion (O + ) number density in the F-region of the ionosphere along the vector from Earth to the satellite; estimating a second atomic oxygen scale height in the F-region of the ionosphere along the vector from Earth to the satellite; estimating an amount of singly charged oxygen ions (O + ) in the F-region of the ionosphere at points along the vector from Earth to the satellite based on the estimated second altitude, the estimated second peak density and the estimated second atomic oxygen scale height; estimating a second intensity of 83.4 nm airglow from singly charged oxygen ions (O + ) along the vector from Earth to the satellite based on the estimated amounts of singly charged oxygen ions (O + ) in the F-region of the ionosphere at the points along the vector from Earth to the satellite; defining a generalized chi-squared function of the first altitude, the first peak density, the first atomic oxygen scale height, the estimated second altitude, the estimated second peak density, the estimated second atomic oxygen scale height, the first intensity and the estimated second intensity; minimizing the generalized chi-squared function by varying at least one of the estimated second altitude, the estimated second peak density and the estimated second atomic oxygen scale height to determine optimal estimates of the estimated second altitude, the estimated second peak density and the estimated second atomic oxygen scale height; and determining the altitude profile of the amount of singly charged atomic oxygen ions (O + ) in the F-region of the ionosphere between the Earth and the satellite based on the optimal estimates of the estimated second altitude, the estimated second peak density and the estimated second atomic oxygen scale height.