AO-73 : Funcube -1

Spin Period
04 Oct 2019 = 22.7 seconds (from averaged panel temperatures)
05 Oct 2019 = 21.9 seconds (from averaged panel temperatures)
06 Oct 2019 = 21.4 seconds (from averaged panel temperatures)
07 Oct 2019 = 20.9 seconds (from averaged panel temperatures)
08 Oct 2019 = 21.3 seconds (from averaged panel temperatures)
09 Oct 2019 = 20.8 seconds (from averaged panel temperatures)
10 Oct 2019 = 20.4 seconds (from averaged panel temperatures)

Over the last week AO-73 has continued to spin, reverse to what we know as the normal direction.
On the 8th October AO-73 started to exhibit a level of instability that indicated it was about to commence tumbling again.

73 de Colin VK5HI.

AO-73 : Funcube-1

Spin Period
27 Sep 2019 = 30.4 seconds (from averaged panel temperatures)
28 Sep 2019 = 29.3 seconds (from averaged panel temperatures)
29 Sep 2019 = 28.0 seconds (from averaged panel temperatures)
30 Sep 2019 = 27.0 seconds (from averaged panel temperatures)
01 Oct 2019 = 25.8 seconds (from averaged panel temperatures)
02 Oct 2019 = 24.8 seconds (from averaged panel temperatures)
03 Oct 2019 = 23.7 seconds (from averaged panel temperatures)

Over the last week AO-73 has continued to spin, reverse to what we know as the normal direction.
This week AO-73 has again maintained a high level of Nutation.

73 de Colin VK5HI.

AO-73 : Funcube-1

Spin Period
20 Sep 2019 = 40.8 seconds (from averaged panel temperatures)
21 Sep 2019 = 39.3 seconds (from averaged panel temperatures)
22 Sep 2019 = 37.8 seconds (from averaged panel temperatures)
23 Sep 2019 = 36.1 seconds (from averaged panel temperatures)
24 Sep 2019 = 34.5 seconds (from averaged panel temperatures)
25 Sep 2019 = 33.1 seconds (from averaged panel temperatures)
26 Sep 2019 = 31.4 seconds (from averaged panel temperatures)

Over the last week AO-73 has continued to spin, reverse to what we know as the normal direction.
This week AO-73 has again maintained a high level of Nutation.

73 de Colin VK5HI.

AO-73 : Funcube-1

Spin Period
13 Sep 2019 = 53.7 seconds (from averaged panel temperatures)
14 Sep 2019 = 52.3 seconds (from averaged panel temperatures)
15 Sep 2019 = 50.1 seconds (from averaged panel temperatures)
16 Sep 2019 = 48.4 seconds (from averaged panel temperatures)
17 Sep 2019 = 46.4 seconds (from averaged panel temperatures)
18 Sep 2019 = 44.5 seconds (from averaged panel temperatures)
19 Sep 2019 = 42.8 seconds (from averaged panel temperatures)

Over the last week AO-73 has continued to spin, reverse to what we know as the normal direction. This week AO-73 has maintained a high level of Nutation.

73 de Colin VK5HI.

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.

AO-73 : Funcube – 1

Spin Period
16 Aug 2019 = 23.8 seconds (from averaged panel temperatures)
17 Aug 2019 = 22.4 seconds (from averaged panel temperatures)
18 Aug 2019 = 20.8 seconds (from averaged panel temperatures)
19 Aug 2019 = 19.8 seconds (from averaged panel temperatures)
20 Aug 2019 = 18.7 seconds (from averaged panel temperatures)
21 Aug 2019 = 17.6 seconds (from averaged panel temperatures)
22 Aug 2019 = 15.1 seconds (from sun sensor data)

AO-73 has over the last two days commenced to tumble.
This is noticeable on the downlink signal.

73 de Colin VK5HI.

AO-73 : Funcube-1

Spin Period
09 Aug 2019 = 41.1 seconds (from averaged panel temperatures)
10 Aug 2019 = 37.8 seconds (from averaged panel temperatures)
11 Aug 2019 = 35.1 seconds (from averaged panel temperatures)
12 Aug 2019 = 32.6 seconds (from averaged panel temperatures)
13 Aug 2019 = 29.8 seconds (from averaged panel temperatures)
14 Aug 2019 = 27.8 seconds (from averaged panel temperatures)
15 Aug 2019 = 26.8 seconds (from averaged panel temperatures)

73 de Colin VK5HI.

AO-73 : Funcube 1

Spin Period
02 Aug 2019 = 68.6 seconds (from averaged panel temperatures)
03 Aug 2019 = 65.0 seconds (from averaged panel temperatures)
04 Aug 2019 = 60.2 seconds (from averaged panel temperatures)
05 Aug 2019 = 56.3 seconds (from averaged panel temperatures)
06 Aug 2019 = 52.1 seconds (from averaged panel temperatures)
07 Aug 2019 = 48.1 seconds (from averaged panel temperatures)
08 Aug 2019 = 44.8 seconds (from averaged panel temperatures)

Both my solar prediction programs, Stacey W4SM’s SolarC.exe and Mike DK3WN’s Illum.exe both showed AO-73 entered full sun early on the UTC morning of the 9th August.
Over the last week AO-73 has developed a small level of Nutation associated with increased rotational speed.

73 de Colin VK5HI.