AO-73 : Funcube-1

Spin Period
06 Sep 2019 = 66.4 seconds (from averaged panel temperatures)
07 Sep 2019 = 65.2 seconds (from averaged panel temperatures)
08 Sep 2019 = 63.6 seconds (from averaged panel temperatures)
09 Sep 2019 = 61.4 seconds (from averaged panel temperatures)
10 Sep 2019 = 59.5 seconds (from averaged panel temperatures)
11 Sep 2019 = 57.4 seconds (from averaged panel temperatures)
12 Sep 2019 = 55.5 seconds (from averaged panel temperatures)

Over the last week AO-73 has continued to spin, reverse to what we know as the normal direction. In recent days increased Nutation has developed.
Based on past observations we should expect AO-73 to commence tumbling in coming days.
This may or may not result in AO-73 returning to its normal spin sequence.

73 de Colin VK5HI.

AO-73 : Funcube-1

Spin Period
30 Aug 2019 = 52.2 seconds (from averaged panel temperatures)
31 Aug 2019 = 61.8 seconds (from averaged panel temperatures)
01 Sep 2019 = 66.3 seconds (from averaged panel temperatures)
02 Sep 2019 = 69.9 seconds (from averaged panel temperatures)
03 Sep 2019 = 71.7 seconds (from averaged panel temperatures)
04 Sep 2019 = 69.1 seconds (from averaged panel temperatures)
05 Sep 2019 = 68.8 seconds (from averaged panel temperatures)

By the 29th August AO-73 had achieved a very unstable tumble.
On the 30th August that tumble ceased with a resultant Spin Reversal but with minimal Nutation.
That spin reversal has been maintained since the 30th August.
With reference to the Z+ and Z- Sun Sensors values over VK, I have noted that the “flip” near the South Magnetic Pole appears to have negligible affect on the spin direction.
A download of telemetry from the Northern Hemisphere by Rocky, W2RTV helped my analysis significantly. Thank You Rocky.

The above analysis indicates AO-73 may be increasing in speed again.
?? Another tumbling period. -> spin reversal. ??

73 de Colin VK5HI.

AO-73 : Funcube-1

Spin Period
23 Aug 2019 = 17.5 seconds (from sun sensor data)
24 Aug 2019 = 17.5 seconds (from sun sensor data)
25 Aug 2019 = 18.5 seconds (from sun sensor data)
26 Aug 2019 = 22.3 seconds (from sun sensor data)
27 Aug 2019 = 26.8 seconds (from sun sensor data)
28 Aug 2019 = 31.4 seconds (from averaged panel temperatures)
29 Aug 2019 = 42.2 seconds (from sun sensor data)

AO-73 continues to tumble.
This is very noticeable on the downlink signal.

73 de Colin VK5HI.