Bob The following link is of Picodragon and 2 other satellites being released or launched. There is a picture and short video. http://amsat-uk.org/tag/picodragon/
73 John KC0BMF On Mon, Nov 25, 2013 at 9:54 AM, Robert Bruninga <bruni...@usna.edu> wrote: > Ø When there is a launch of several satellites in a single payload, > several cubesats for example, I assume they release each at > different locations on the deployer trajectory. Preliminary keps are based > on the trajectory when each is released? > > Ø Otherwise if they were released all at once, how would NORAD know which > is which? > > > Doesn’t much matter when they are released, they still are all in the same > orbit more or less for quite a while. Even if the springs release them at > 1/2 meter per second, they are all going at 7000 meters per second so it > takes days for them to separate very much. > > > > Let’s see, at ½ meter per second separation, then they are 100’ apart > after the first minute, 1 mile after the first hour. And not until they > are a few miles apart can NORAD distinguish them enough to start getting > good tracks on them. By then it is impossible to know which is which. > Hence the guessing game until each owner decides which object best fits his > downlink experience. > > > > Continuing on, they will be 24 miles apart after the first day where they > will be about 5 seconds apart when tracked from the ground. After a week, > then maybe 175 miles and ½ minute apart. After a month, maybe 750 miles > and 2 minutes apart. After a year, maybe 9000 miles and 30 minutes apart. > And finally, after about a year and a half, they will be half an orbit or > about 45 minutes apart, beyond which, they start getting closer again… > > > > Something like that unless I screwed up… > > > > Bob > _______________________________________________ > 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 > _______________________________________________ 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