[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

RE: Re: AO-40: more successful ARCJET operations



Mineo -- Nice work. The perigee difference is probably due to your
definition of altitude, i.e. distance from the surface of the earth. You
said:

> (18) r0=a(1-e^2)/(1+e*cos(s))   : Height from the center of the earth
> (19) r=r0-6371                  : Height from the face of the earth

The equatorial radius of the oblate earth is 6378.160 km, larger than
the 6371 km you use. Since the inclination is only 5.3 deg, it is
appropriate to use the equatorial value.

Therefore, using your formulation, I come up with:

> The solution of this algorism [posted by JE9PEL]
>                     Before      After
>   Perigee height :   286.0        288.4  ....... +2.4 km
>
> The report of Peter Guelzow, DB2OS
>                     Before      After
>   Perigee height :   279.754      282.2427  .... +2.5 km

  The JE9PEL perigee corrected by W3IWI:
                      Before        After
    Perigee height :   278.8        281.3  ....... +2.5 km

This agrees to ~1 km with the results that Peter reported. Since the
object of the "burn" was to raise perigee (with very little change in
apogee), and since a post-burn mean motion is not yet available, I
haven't bothered to examine the apogee differences.

73 de Tom, W3IWI

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


AMSAT Top AMSAT Home