Greetings, all:
How do you determine the orbit number of a satellite, and what are the conventions to determining when the orbit number changes?
Thanks in advance for the information.
-- bag KL7CN/W6 CM98fn
The orbit number changes when the satellite crosses the equator travelling in a South to North direction. I don't know whether orbits where the satellite is still attached to the launch vehicle count.
Bryan Green wrote:
Greetings, all:
How do you determine the orbit number of a satellite, and what are the conventions to determining when the orbit number changes?
Thanks in advance for the information.
-- bag KL7CN/W6 CM98fn _______________________________________________ Sent via AMSAT-BB@amsat.org. 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
If I recall correctly, a new orbit, or orbit number increase, occurs when the satellite crosses the equator from the southern hemisphere to the northern hemisphere.
73,
Jeff WB3JFS
----- Original Message ----- From: "Bryan Green" bag@mac.com To: "AMSAT-BB" amsat-bb@amsat.org Sent: Friday, November 28, 2008 7:09 AM Subject: [amsat-bb] Determining orbit number
Greetings, all:
How do you determine the orbit number of a satellite, and what are the conventions to determining when the orbit number changes?
Thanks in advance for the information.
-- bag KL7CN/W6 CM98fn _______________________________________________ Sent via AMSAT-BB@amsat.org. 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
But do the orbits whilst it is still attached to the launch vehicle count? And do partial orbits count (i.e. if it is launched from a site just south of the equator in a northerly direction the first eqx would be only after a very small portion of an orbit) or only complete orbits?
Jeff Yanko wrote:
If I recall correctly, a new orbit, or orbit number increase, occurs when the satellite crosses the equator from the southern hemisphere to the northern hemisphere.
73,
Jeff WB3JFS
I was told that while the bird(s) is still attached to the rocket body the orbital count increases to all objects by 1 by each passing of the equator in the south to north movement. In most cases the bird separates from the body well before the first orbit is completed, yet when it reaches the equator on it's south to north move, orbit number 00001 is logged.
As for determining the orbit number with a launch site south of the equator it would be the second south to north equatorial crossing after launch since the first crossing wouldn't count since it was just lauched and hasn't completed a whole, or near whole orbit or achived orbit.
Now here's a kicker. If a bird is launched from the southern hemisphere and it headed in a southerly direction, towards the south pole it would cross the equator south to north on its first equatorial pass but won't count as an orbit until the next pass. Which would technically mean the bird would have to orbit, say 1.25 to 1.5 times before the first "official" orbit is logged.
73,
Jeff WB3JFS
----- Original Message ----- From: "Nigel Gunn G8IFF/W8IFF" nigel@ngunn.net To: "AMSAT-BB" amsat-bb@amsat.org Sent: Friday, November 28, 2008 12:02 PM Subject: [amsat-bb] Re: Determining orbit number
But do the orbits whilst it is still attached to the launch vehicle count? And do partial orbits count (i.e. if it is launched from a site just south of the equator in a northerly direction the first eqx would be only after a very small portion of an orbit) or only complete orbits?
Jeff Yanko wrote:
If I recall correctly, a new orbit, or orbit number increase, occurs when the satellite crosses the equator from the southern hemisphere to the northern hemisphere.
73,
Jeff WB3JFS
Sent via AMSAT-BB@amsat.org. 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
No, it would cross the equator on a S to N direction around half an orbit after launch.
Jeff Yanko wrote:
Now here's a kicker. If a bird is launched from the southern hemisphere and it headed in a southerly direction, towards the south pole it would cross the equator south to north on its first equatorial pass but won't count as an orbit until the next pass. Which would technically mean the bird would have to orbit, say 1.25 to 1.5 times before the first "official" orbit is logged.
I believe that's what is stated in the paragraph below, South to North.
73,
Jeff WB3JFS
----- Original Message ----- From: "Nigel Gunn G8IFF/W8IFF" nigel@ngunn.net To: "Jeff Yanko" wb3jfs@cox.net Cc: "AMSAT-BB" amsat-bb@amsat.org Sent: Friday, November 28, 2008 12:31 PM Subject: Re: [amsat-bb] Re: Determining orbit number
No, it would cross the equator on a S to N direction around half an orbit after launch.
Jeff Yanko wrote:
Now here's a kicker. If a bird is launched from the southern hemisphere and it headed in a southerly direction, towards the south pole it would cross the equator south to north on its first equatorial pass but won't count as an orbit until the next pass. Which would technically mean the bird would have to orbit, say 1.25 to 1.5 times before the first "official" orbit is logged.
participants (3)
-
Bryan Green -
Jeff Yanko -
Nigel Gunn G8IFF/W8IFF