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Quiet regions on the Sun are becoming more and more common as solar activity decreases. The decrease of emerging active regions allows existing magnetic fields to relax into what is called a potential configuration. The region highlighted in the image shows a potential arcade loop, a necessary magnetic configuration for prominence formation.
Hinode XRT took 11s exposures using the thin-Be filter. A movie of the averaged data hints of structures inside the igloo-like arcade. An enhanced image of the region shows the contrast between the bright arcade loops and dark regions below. The location and the complex structure of the dark bands suggest a prominence could be struggling to form.
A quick look at an SDO/AIA image also hints of a prominence but a stable one never appears. Perhaps it is still too early and more time is needed. We can check back on 28 December 2015, when this region of the Sun will be near the east limb again.