Panel a: single-dish ALMA 248 GHz (1.21 mm, Band 6). Panel b: SDO-HMI magnetogram, with white box outlining the quiet Sun area shown in middle row panels. Both images were taken on 18 December 2015 at 20:12 UT. Magnetogram intensity was clipped at ±120 Gauss and ALMA contours of 6500 K were overlaid in green. Panel c: ALMA image of the quiet Sun shown enlarged and compared with panel d: SDO-HMI magnetogram, panel e: SDO-AIA 193 Å filtergram, and panel f: GOES-13 SXI tin (Sn) filter image, with ALMA contours overlaid (levels at 6300, 6400, 6500, 6600, and 6700 K). Panels g–j: enlargements of a single ALMA bright feature, marked in the white rectangle in panel c, at the same wavelengths as in the middle row. The beam size of the single-dish ALMA measurements, 26″, is given in panel c.