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Satellite orbits .

Satellite orbits . Where is the satellite ? May we see it ?. CTS Referencesystem. Fixed with respect to the Earth. /. Inertial system. Newtons laws valid. Center in Gravity center Fixt in relation to The Fix-stars. Connection to CT Through siderial Time.

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Satellite orbits .

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  1. Satelliteorbits. Where is the satellite ? May wesee it ? Satellite geophysics, 2013-11-10
  2. CTS Referencesystem. Fixed with respect to the Earth. / Satellite geophysics, 2013-11-10
  3. Inertial system. Newtons laws valid. Center in Gravity center Fixt in relation to The Fix-stars. Connection to CT Through siderial Time. Satellite geophysics, 2013-11-10
  4. Satellitemoventaround ideal Earth. Spherical, homogeous, noathmosphere Newtons law of attraction: Force= F =G(Mm)/r2 M=Earth mass, m = satellittemass G= gravitationalconstant, r distance from C. / Satellite geophysics, 2013-11-10
  5. Orbit is curve in 3D-space. Orbitalcurve: Acceleration Force 2. orderdifferentalequation If in ONE point weknow: Velocity-vector (3 numbers) Position (3 numbers) Determinesorbit ! (6 numbers) State-vector Satellite geophysics, 2013-11-10
  6. The Kepler laws as consequences of the law of attraction 1. Law: Orbit is elliptic, with 1 focus in the gravity center of the Earth. Orbital plane fix in inertial coordinate-system – tree constants fixed. Witha, e 5 constants fixed ! / f b a C Satellite geophysics, 2013-11-10
  7. Kelper’s 2. law. Areas covered by the position-vector is proportional with time, t. Velocity of Satellite is NOT constant. Minumum: Apogee Maximum: Perigee Satellite geophysics, 2013-11-10
  8. Kepler’s 3. law. Satellite geophysics, 2013-11-10
  9. 3. law: Consequence: 2 satellites with same semi-major axis will have same revolution time, T, independent of the excentricity. / Satellite geophysics, 2013-11-10
  10. 6 Kepler-elements Position given by statevector or 6 Kepler- elements = Ascending nodes rectancention, i: orbit inclination, = perigee argument a= semi major axis, e: excentricity, f=latitude, Satellite geophysics, 2013-11-10
  11. Computation ofstate-vector from Kepler-elementer Coordinat system in Orbital plane, center in C. Polar coordinates f, r. E: excentric anomaly Satellite geophysics, 2013-11-10
  12. Velocity and angular velocity Linar in time ! Orbit is straight line expressed in Kepler-elementes in the 6-dimensional space Satellite geophysics, 2013-11-10
  13. To Inertial system by Rotations: Position = Rxqq, Velocity= Rxqq’ Composed of 3 rotations / Satellite geophysics, 2013-11-10
  14. Satellitorbits GPS, i= 55 - Torge 5.2. Satellite geophysics, 2013-11-10
  15. Forces acting on the satellite. Fc= Ideal spherical Earth, Fnc= deviation from ideal Fn,Fsfrom Sun and Moon Fr , solar pressure Fa=atmosphere, Tides, Magnetic Field / Satellite geophysics, 2013-11-10
  16. Satellite orbits – influence of non-central force. / Satellite geophysics, 2013-11-10
  17. Satellit orbits, solar pressure, atmosphere Forces depend on shade/non shade of sun. Relationship masse/surface area. Variations of 2 m. Depends on density of atmosphere, satellite diameter, mass and velocity. v=7500 m/s, force0.000001 m/s2 Neglicible for GPS. / Satellite geophysics, 2013-11-10
  18. Satellit-orbits – other bodies and mass changes. Moon most important, Planets small effect Earthdeformation, tides/loading Seasonal masse-changes. Satellite geophysics, 2013-11-10
  19. Satellit orbits – description of changes. 16 parametres, Update Every hour. Satellite geophysics, 2013-11-10
  20. Satellite orbital parameters for GPS Mean anomaly Mean movement difference Excentricity Square-roor of a Right acension Inclination att0e Perigee argument Time derivative of rectac. Time derivative of i Correction to f Correction to r Corrections to i Reference-time Satellite geophysics, 2013-11-10
  21. Computation of position, Torge p. 132. GM=3.98608x1014 m3/s2, =7.292115147x10-5 rad/s2 Trueanomaly fkfrom time-difference tk=t-t0e Mean-anomali: Solution iterativly wrt Ek, Satellite geophysics, 2013-11-10
  22. Satellit orbits . LEO: Low Earth Orbit h < 2000 km MEO: Medium Earth Orbit 5000-20000 km GEO: Geostationary, h=36000 km IGSO: Inclined Geo-syncronous Orbit HEO: Highly Elliptic Orbit Satellite geophysics, 2013-11-10
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