Thanks Robert! Clear now. 73s Fabio iw8qku/5
On Fri, Jan 13, 2012 at 4:59 PM, Robert McGwier <[email protected]> wrote: > These maneuvers are not done continuously around the orbit. They are > typically done in burns done at apogee and perigee if all they are doing is > raising/lowering the orbit and minimizing any changes to the orbital plane. > > Think of it like this. When I turn the propulsion on, I do not change my > CURRENT instantaneous position while I am burning. What I change is my > velocity. So if I burn the motor at apogee and the motor is firing along > my velocity vector, then I am speeding myself up. THIS RAISES PERIGEE > because I will have the same height but my speed will cause the position on > the OTHER SIDE of the orbit to be raised. Similarly, I slow down at > apogee, perigee is lowered. If I speed up at perigee, apogee is raised, > ........ > > Did this help? > > Bob > > > On Fri, Jan 13, 2012 at 10:28 AM, Fabio Azzarello <[email protected]>wrote: > >> Hello everybody, >> >> ISS heights plots are available at the following link: >> >> http://www.heavens-above.com/OrbitHeight.aspx?satid=25544&startMJD=55610&lat=43&lng=11 >> >> I've noticed that Apogee and Perigee heights have different behaviour >> during reboosts (look at mid September for example), >> could anybody help me to understand why? >> >> Thanks in advance, >> 73s >> Fabio >> iw8qku/5 >> _______________________________________________ >> Sent via [email protected]. Opinions expressed are those of the author. >> Not an AMSAT-NA member? Join now to support the amateur satellite program! >> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb >> > > > > -- > Bob McGwier > Facebook: N4HYBob > ARS: N4HY > > > _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
