Satellite Orbit and Ephemeris Determination using Inter Satellite Links

Orbit ComputationInter Satellite LinksAmareamassρ air densityr D velocity vector with respect to earth centred earth fixed coordinatesAgain, shape and attitude of the satellite are simplified for the sake of generality, bycharacterising the satellite using the so called ballistic coefficientc D⋅ AEq. 4.2-50mDetermination of the air density is the most critical part in Eq. 4.2-49. It is subject to variationin solar flux and very difficult to model. Normally, the air density is modelled as aexponential function over a certain altitude range h L < h < h U .ρh−hH0( h) = ρ ⋅ ewith the so called scale heightLLEq. 4.2-51andH 0R ⋅ T=gρ(h) air density at altitude hρL air density an lower bound of altitude rangeR special gas constant (for air: 287 J / (kg * K))T Thermodynamic temperature in Kelving GravityEq. 4.2-52The following table, found in [WEZ-91], indicates the parameters for an atmospheric model:Page 34R. Wolf