SEEDS

0005 UTC
Has anyone listened to SEEDS and wondered why at times it exhibits deep fading.
Maybe the following information will assist to explain why that occurs.
The explanation ignores the effects of potential Faraday Rotation etc.

The following graphic shows the Rotational Status of SEEDS (Cubesat Oscar 66) while over Australia. It can be observed that the craft is rotating around the Y-Y Axis at approximately 270 seconds per revolution. The satellite is also exhibiting Nutation or “wobble” about the Y-Y Axis. This is highlighted by the +Y and -Y Axis current values.
Prior to the acquisition of signals it can be deduced that the Y-Y axis flipped over relative to the Sun. Just prior to AOS the -Y face was being illuminated, followed by the +Y axis being illuminated during the Nutational period at a period of nominally 210 seconds.

Please note:
The timing values are made on the assumption that each AFSK frames is telemetered at 1.2 seconds.
seeds-afsk-0005utc-1405091

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