*HI all,Found this at this page:http://www.amsat.org/amsat/articles/g3ruh/111.html http://www.amsat.org/amsat/articles/g3ruh/111.htmlOrbit Plane:* Fixed (almost) with respect to the stars, in orientation defined by argument of perigee, inclination and RAAN. Origin: Earth's centre. X: Directed towards perigee Y: 90 degrees from perigee round the orbit in direction of satellite's motion Z: Perpendicular to orbit plane I think I understand most of the math in the algorithm. In the above context, what does RAAN mean? Sorry for being obtuse! Norm n3ykf
HI,
Right Ascention of the Ascending node.
The point in the orbit at which it crosses the equator going northbound.
Here 's a good example:
http://www.pe0sat.vgnet.nl/satellite/
73
Dave, G4DPZ
On 24/01/14 08:59, Lizeth Norman wrote:
*HI all,Found this at this page:http://www.amsat.org/amsat/articles/g3ruh/111.html http://www.amsat.org/amsat/articles/g3ruh/111.htmlOrbit Plane:* Fixed (almost) with respect to the stars, in orientation defined by argument of perigee, inclination and RAAN. Origin: Earth's centre. X: Directed towards perigee Y: 90 degrees from perigee round the orbit in direction of satellite's motion Z: Perpendicular to orbit plane I think I understand most of the math in the algorithm. In the above context, what does RAAN mean? Sorry for being obtuse! Norm n3ykf _______________________________________________ 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
Right Angle (of the) Ascending Node? I think I got it. Much to play with here. Norm n3ykf
On Fri, Jan 24, 2014 at 4:38 AM, David Johnson [email protected]wrote:
HI,
Right Ascention of the Ascending node.
The point in the orbit at which it crosses the equator going northbound.
Here 's a good example:
http://www.pe0sat.vgnet.nl/satellite/
73
Dave, G4DPZ
On 24/01/14 08:59, Lizeth Norman wrote:
*HI all,Found this at this page:http://www.amsat.org/amsat/articles/g3ruh/111.html http://www.amsat.org/amsat/articles/g3ruh/111.htmlOrbit Plane:* Fixed
(almost) with respect to the stars, in orientation defined by argument of perigee, inclination and RAAN. Origin: Earth's centre. X: Directed towards perigee Y: 90 degrees from perigee round the orbit in direction of satellite's motion Z: Perpendicular to orbit plane I think I understand most of the math in the algorithm. In the above context, what does RAAN mean? Sorry for being obtuse! Norm n3ykf _______________________________________________ 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
Yes, but one thing I've never quite understood was how to convert RAAN into Longitude. All the neat explanations on non-earthly frames of reference and vernal equinoxes stop short of explaining how to start with RAAN (in a set of elements) and compute forward in time from the epoch to get the longitude of the ascending node of the current orbit. Anyone with a link to an online resource that can help make this clear?
On 01/24/2014 05:38 AM, David Johnson wrote:
HI,
Right Ascention of the Ascending node.
The point in the orbit at which it crosses the equator going northbound.
Here 's a good example:
http://www.pe0sat.vgnet.nl/satellite/
73
Dave, G4DPZ
On 24/01/14 08:59, Lizeth Norman wrote:
*HI all,Found this at this page:http://www.amsat.org/amsat/articles/g3ruh/111.html http://www.amsat.org/amsat/articles/g3ruh/111.htmlOrbit Plane:* Fixed (almost) with respect to the stars, in orientation defined by argument of perigee, inclination and RAAN. Origin: Earth's centre. X: Directed towards perigee Y: 90 degrees from perigee round the orbit in direction of satellite's motion Z: Perpendicular to orbit plane I think I understand most of the math in the algorithm. In the above context, what does RAAN mean? Sorry for being obtuse! Norm n3ykf _______________________________________________ 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
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
Hi Norm,
RAAN = right ascension of the ascending node
http://www.amsat.org/amsat/keps/kepmodel.html#raan
73 Mike Dk3WN
-----Ursprüngliche Nachricht----- Von: [email protected] [mailto:[email protected]] Im Auftrag von Lizeth Norman Gesendet: Freitag, 24. Januar 2014 10:00 An: <,[email protected]>, Betreff: [amsat-bb] G3RUH plan 13 algorithm help
*HI all,Found this at this page:http://www.amsat.org/amsat/articles/g3ruh/111.html http://www.amsat.org/amsat/articles/g3ruh/111.htmlOrbit Plane:* Fixed (almost) with respect to the stars, in orientation defined by argument of perigee, inclination and RAAN. Origin: Earth's centre. X: Directed towards perigee Y: 90 degrees from perigee round the orbit in direction of satellite's motion Z: Perpendicular to orbit plane I think I understand most of the math in the algorithm. In the above context, what does RAAN mean? Sorry for being obtuse! Norm n3ykf _______________________________________________ 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
participants (4)
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David Johnson -
Gus -
Lizeth Norman -
Mike Rupprecht