dscc5937.jpg

The mast on which the Unified S-Band high gain antenna is mounted.

Note that the antenna is mounted approximately 180° from its proper mounting position (because the antenna wouldn't be visible in the display if it were mounted in the correct location).

There are relatively few in-flight photos of the USB antenna, but ones I did find (e.g., AS15-88-11961 and AS15-88-11969) do not show the Kapton insulation depicted here. Pre-flight photos (e.g., S69-19197 and S75-26904) also lack the insulation, but it's hard to say whether insulation might have been added after those pre-flight photos were taken.