Modeling the behavior of hot oxygen ions

Zettergren, M. D.; Oliver, W. L.; Blelly, Pierre Louis; Alcaydé, D.

doi:10.5194/angeo-24-1625-2006

Cited by 3 publications

(2 citation statements)

References 22 publications

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“…4, the dispersion of experimental estimates of O h concentration at 400-500 km is very Zettergren et al (2006);6, Hubert and Gerard (1999).…”

Section: Discussionmentioning

confidence: 99%

“…However, in practical calculations, a diffusive equilibrium density profile is used with a reference density of 0.1-1% at an altitude of 400 km (Alcayde et al, 2001;Zettergren et al, 2006) with T h 4000-5000 K. These altitude profiles of the O h population are taken in order to fit the experimental data. However, they do not have much physical basis.…”

Section: Discussionmentioning

confidence: 99%

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Global modeling of hot O distribution in the upper thermosphere

Бессараб¹,

Korenkov²

2011

Earth Planet Sp

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The existence of hot oxygen (hot O, O h ) in the upper thermosphere is mainly confirmed by optical observations of high-altitude airglow. In the experiments described here, a peak of O h population was found at an altitude of approximately 550 km with a temperature of about 4000 K. Although it was shown that O h concentration could reach a value of 1-2% with respect to ambient (cold) O, a realistic global distribution of O h concentration and temperature has not been established. The presence of non-thermal atoms in the thermosphere leads to variations in the thermo-dynamical regime in the upper atmosphere. The major chemical processes involved in O h production were taken into account in the time-dependent, Global Self-consistent Model of Thermosphere, Ionosphere and Protonosphere (GSM TIP) of the Earth in order to simulate global distribution of O h concentration and temperature (T h ). Calculations were carried out in the geomagnetic coordinate system for moderate solar, quiet geomagnetic conditions, and winter season. It was shown that the maximum O h is located at −60• latitude, 300• longitude, and 24 UT. The T h maximum is about 2050 K. This temperature and O h concentration cause an increase in neutral gas temperature at high thermosphere by ∼100 K during daytime and by ∼70 K during nighttime. Variations in the neutral gas velocity circulation were calculated. The maximum increase in neutral velocity was about 36 m/s, corresponding to = 50• , = 180• in the northern and = −50• , = 270• in the southern hemisphere.

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“…4, the dispersion of experimental estimates of O h concentration at 400-500 km is very Zettergren et al (2006);6, Hubert and Gerard (1999).…”

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Global modeling of hot O distribution in the upper thermosphere

Бессараб¹,

Korenkov²

2011

Earth Planet Sp

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Spacecraft drag modelling

Prieto

Graziano

Roberts

2014

Progress in Aerospace Sciences

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This paper reviews currently available methods to calculate drag coefficients of spacecraft traveling in low Earth orbits (LEO). Aerodynamic analysis of satellites is necessary to predict the drag force perturbation to their orbital trajectory, which for LEO orbits is the second in magnitude after the gravitational disturbance due to the Earth's oblateness. Historically, accurate determination of the spacecraft drag coefficient (C D ) was rarely required. This fact was justified by the low fidelity of upper atmospheric models together with the lack of experimental validation of the theory. Therefore, the calculation effort was a priori not justified. However, advances on the field, such as new atmospheric models of improved precision, have allowed for a better characterization of the drag force. They have also addressed the importance of using physically consistent drag coefficients when performing aerodynamic calculations to improve analysis and validate theories. We review the most common approaches to predict these coefficients.

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