REVOSAT

suivi des satellites artificiels

07 septembre 2007

ABOUT USA 129

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We saw that spy satellite only when it is near the perigee because when apart, it is too high (See Revosat on 31 may 07).
So we drew the visibility diagram with the argument of perigee printed on the 22H30 line, time when the Zenital Ascending Transit ZAT will take  place on this summer .
Precession of ascending node -.01124 degrees/day=-16.42 mn/year
Precession of perigee –3.26 degrees/day
Period 1.624H.
We saw that at the beginning of September there is a spell of visibility. To get a better prediction, we computed the height and the speed of the satellite versus the true anomaly so when it is over FRANCE we can estimate its height. The argument of perigee versus date  is drawn after the data published in heavens Above site.

Posté par revosat à 16:16 - Observation - Commentaires [1] - Permalien [#]

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