David, Check this out.
http://celestrak.com/NORAD/documentation/tle-fmt.asp 73 W9KE Tom Doyle On Wed, Sep 19, 2012 at 7:19 PM, David A. Rush <[email protected]> wrote: > I've been working on some code to decode the two-line Keplerian data like > the ARRL sends out weekly (with a thank-you to AMSAT-NA). > > A couple of the values are in a somewhat cryptic format, the "BSTAR" and > "second derivative of the mean motion". The strings tend to be either a > space or a + sign, five digits, usually a minus sign (but seen at least once > as a plus sign) and finally another digit, such as: > > +00000-0 > +11682-3 > 00000-0 > 30767-3 > 00000-0 > 00000+0 > +00000-0 > +89689-4 > > What I have found about this format is that it is "decimal assumed", and > examples suggest that +89689-4 = 0.89689 * 10 ^-4 or 0.000089689, if I > converted that correctly. > I'm guessing that the first character is the sign (+ or -) of the number, > where a space is assumed positive. I've only seen one example of the 7th > character being a plus (and all the digits were zero), so I assume that + or > - are valid values for the exponent. I guess the format is fundamentally > limited to an exponent between +9 and -9. > > Am I interpreting it correctly? Any other insight? > > David, ky7dr > _______________________________________________ > 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 from my computer. tom ... _______________________________________________ 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
