Friday, 27 November 2020

USA 310 (NROL-101) and it's Centaur on 25 November

click image to enlarge

The image above was taken between 1:28:22 - 1:28:27 UT on November 25, and shows both USA 310 (the NROL-101 payload) and its Centaur upper stage in one image. 

At the moment of imaging they were only some 48 arcminutes apart in the sky. Their real distance to each other was ~541 km. The image was made with a Canon EOS 80D and Samyang 2.0/135 mm lens.

Since launch the Centaur, which is is a somewhate lower, more eccentric orbit than the payload, has gained one complete lap on the payload, and it was overtaking it while I was imaging them in the early hours of  November 25. Their closest approach (at a very safe distance of 533 km) was  a few minutes after the image above, at 1:33:29 UT (25 November 2020).

Note the brightness difference between the two, the Centaur upper stage being clearly brighter than the payload. In this image, the Centaur is near the peak of its periodic brightness variation. In a previous post I have detailed the character of the brightness variation of the Centaur.


gammaray said...

Hi, there is a small typo in your headline: It should be NROL-101 instead of NROL-31.

SatTrackCam Leiden said...

Thanks for catching that one! I have now corrected it. very odd mistake...