Originally Posted by NASA

Tensioning of all 5 layers of the sunshield is complete which puts the sunshield in its fully deployed state.

Temperatures on the Sun/hot side of the sunshield will reach a maximum of approximately 383K or approximately 230 degrees F and on the cold mirror/instruments side of the sunshield, a minimum of approximately 36K or around -394 degrees F. Due to the engineering of the sunshield, this incredible transition takes place across a distance of approximately six feet.