Sycorax, or Uranus XVII


Sycorax was discovered with the 5m Hale telescope at Palomar in September 1997 just 23 years before this image was taken on 2020-09-14. The satellite is only 150 km in diameter and was 2978 million km distant at that time, when it then had a V magnitude of 20.7. Sycorax is marked with the cross-lines; the star indicated with an asterisk is Gaia EDR3 75009958852730496, catalogued at magnitude g=19.03. A good number of background galaxies are also visible in this image, ranging in magnitude from 18.5 or so down to perhaps 21.5 though I have not yet identified and found good data for any of them.

The background glow at the top-right of the image comes from Uranus itself which is well outside the frame.

Image information
Date and time of observation  2020-09-14 03:00 UT
Telescope 0.4m f/6.5 Dilworth-Relay
Camera Starlight Xpress Trius-PRO SX814 CCD
Filter None
Exposure 8230s in 137 subs, median-stacked on the mean motion of the satellite
Centre of image RA 02h31m25.5s  Dec +14°18'58"
Image dimensions 10.7 arcmin × 6.1 arcmin