In the early morning of 27 February 2018, I was imaging a rocket stage from a classified launch, the NOSS 3-4 r/b, when suddenly a very fast, flashing object entered the FOV, and I followed it as it looked interesting (it was so fast that in the first instance I thought it was a meteor). It turned out to be the cubesat FLOCK 2E 4 (1998-067 JH, #41487).
FLOCK 2E 4 is a cubesat that was released from Cygnus OA-6 in May 2016. It is currently in a 247 x 260 km, 51.6 degree inclined orbit, and from the imagery it is clearly tumbling. It is coming down fast, with several km/day, as it is close to decay. An analysis with SatAna and SatEvo predicts that it will re-enter in about a week, on or near 2018 March 6-7.
The diagram below shows how the orbital altitude changed since it was released at 400 km altitude from Cygnus OA-6 in May 2016:
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| click diagram to enlarge |
FLOCK 2E 4 was built by Planet Labs and was one of the imagers in their FLOCK constellation. It basically is a small 9 cm telescope with a camera, and delivered imagery of the Earth's surface with a resolution of a few meters.
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| FLOCK cubesat (image: Planet Labs) |
It is a very small object, the smallest I have managed to image in Earth Orbit so far. The body measures only 34 x 10 x 10 cm, and with solar panels deployed, the maximum dimension is 34 x 30 cm. A lucky capture!
The camera used was the WATEC 902H with a Canon FD 1.8/50mm lens.
