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How do we get from any arbitrary orbit to M288? The following techniques may not be optimal for minimal $ \Delta V $, but they set an upper bound. We will assume Kepler orbits and a circular M288 destination orbit, and heavy objects unaffected by light pressure. Actual thinsat orbits are elliptical and precess over a year with J2 and light pressure.

|| The origin elliptical Kepler orbit has four parameters we need to compute two $ \Delta V $ burns for our transfer orbit: <<BR>><<BR>> * Apogee $ r_a $ <<BR>><<BR>> * Perigee $ r_p $ <<BR>><<BR>> * Inclination $ i $ <<BR>><<BR>> * argument of perigee $ \omega $ <<BR>><<BR>>We can compute the semimajor axis $ a $ and the eccentricity $ e $ from the apogee and perigee <<BR>><<BR>>The angle of the ascending and descending nodes do not affect the $ \Delta V $ burns, though they do affect when we make our burns so we insert into the desired destination region of the M288 orbit.<<BR>><<BR>>|| {{http://upload.wikimedia.org/wikipedia/commons/thumb/e/eb/Orbit1.svg/2000px-Orbit1.svg.png||width=500}} ||

Manuevers use the least $ \Delta V $ farther out, so we will use different strategies depending on whether the apogee of the origin orbit is higher or lower than the M288 orbit $ r_288 $.

=== Describing an arbitrary Kepler Orbit ===

Assume an x,y,z coordinate space and an orbit in the x,z plane:

||

Changing Orbits to M288

How do we get from any arbitrary orbit to M288? The following techniques may not be optimal for minimal \Delta V , but they set an upper bound. We will assume Kepler orbits and a circular M288 destination orbit, and heavy objects unaffected by light pressure. Actual thinsat orbits are elliptical and precess over a year with J2 and light pressure.

The origin elliptical Kepler orbit has four parameters we need to compute two \Delta V burns for our transfer orbit:

* Apogee r_a

* Perigee r_p

* Inclination i

* argument of perigee \omega

We can compute the semimajor axis a and the eccentricity e from the apogee and perigee

The angle of the ascending and descending nodes do not affect the \Delta V burns, though they do affect when we make our burns so we insert into the desired destination region of the M288 orbit.

http://upload.wikimedia.org/wikipedia/commons/thumb/e/eb/Orbit1.svg/2000px-Orbit1.svg.png

Manuevers use the least \Delta V farther out, so we will use different strategies depending on whether the apogee of the origin orbit is higher or lower than the M288 orbit r_288 .

Describing an arbitrary Kepler Orbit

Assume an x,y,z coordinate space and an orbit in the x,z plane:

||

OrbitChange (last edited 2013-02-17 05:28:58 by KeithLofstrom)