RE: [amsat-bb] AO40 velocity

[Robert McGwier <rwmcgwier@xxxxxxxxxxx>]

Bob:

The Vis-viva equation is what you are looking for I think.


V^2 = mu (2/r  - 1/a)

where r is the distance of the satellite from earth center and
a is the semimajor axis.

mu varies according to the units you use.  If the units are in
earth radii,  then mu is 1 and the velocity squared is given
in (earth radii per second)^2.  You take the square root
of this to get velocity.  If you measure the distances in  meters,
I believe mu is approximately 1501416 if I did the conversion
correctly!

Bob
N4HY


-----Original Message-----
From: owner-AMSAT-BB@AMSAT.Org [mailto:owner-AMSAT-BB@AMSAT.Org]On
Behalf Of Bob V Johnson
Sent: Thursday, August 29, 2002 2:27 PM
To: amsat-bb@AMSAT.Org
Subject: [amsat-bb] AO40 velocity


Hello
I was asked how fast "those things" go.  I took a guess and probably was
fairly correct.  That got me thinking how fast really is it.  Given the
MA, at that part of the orbit is there a formula that would yield the
velocity at that point?  

73...Bob...W7LRD
Seattle, Wa.
"everything is a learning curve"

----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org


----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org