November 21, 2021 marked the eighth anniversary of the FUNcube-1 CubeSat. Remarkably, the tiny spacecraft, launched from Russia on November 21, 2013, continues to perform well after traveling over a billion kilometers in space.
For the past two months, the spacecraft’s orbits have unfolded just along the edge of the terminator. At first, we effectively had full sun without an eclipse, but at the start of this month it seemed like the solar panels were not receiving enough solar radiation to keep the battery fully charged.
FUNcube-1 transmitted continuous high power telemetry and therefore consumed maximum power. The screenshot is from AMSAT-UK / BATC ground station at Goonhilly earth station. The FUNcube dashboard shows the rapid drop in bus voltage from an already below normal level of 8.0V to 7.8V. The spacecraft went into “safe” mode in the aftermath. noon on November 18. This reduced the total power consumption by almost 50% and, as can be seen, the spacecraft is once again in a happy situation of “positive power”.
Although Safe Mode provides less than 20mW of downlink RF, it is remarkable how many stations are still receiving and decoding 1k2 BPSK telemetry. It’s a good time to say a big thank you to the many stations around the world who, even after eight years, continue to submit their data to the FUNcube Data Warehouse. It’s really valuable for the team and it really helped us understand what’s going on up there!
We will continue to monitor telemetry over the next few weeks and plan to return FUNcube-1 to nominal autonomous operation, with the transponder on when the spacecraft is in eclipse, as soon as possible.
Interestingly, it looks like we will have no more “full sun” periods for the foreseeable future. However, the ones we have known have provided good data on the temperature that can reach a 1U CubeSat under such circumstances!