(a)–(c) Hinode/XRT Be-thin filter images at indicated times of a jet from AR 12259, with an HMI magnetogram from 2015 January 14, 14:20 39 UT, overlaid. In the magnetogram, green and blue represent positive and negative polarities, respectively, and the contours are at 50, 100, and 750 G. See Sterling et al. (2017) for more details and videos of this event. (d)–(f) Schematic showing the minifilament eruption coronal jet mechanism suggested by Sterling et al. (2015). [This version of the schematic is adopted from Sterling et al. (2016) by permission of the AAS.] Initially, (d) a cool (chromosphere/transition-region temperature) minifilament (blue circle) resides in a bipole on a magnetic neutral line (A)–(B), adjacent to a larger bipole (B)–(C). Black/red lines represent magnetic field lines before/after reconnection. As the minifilament erupts (e) it encounters the opposite-polarity field on the far side of the larger bipole, with resulting reconnections (red Xs) making a new open field along which the jet spire forms. Also, loop (A)–(B) brightens, forming a jet (or jet-base) bright point; this occurs due to flare-type reconnection occurring among the legs of the erupting minifilament field. As the eruption continues, (f) the spire broadens, and the large bipole (B)–(C) brightens and grows due to the addition of reconnection-formed loops. The long arrows between (d) and (a) show approximate correspondences between the schematic and the observed AR jet. This schematic picture was derived from coronal hole jet observations; the situation in ARs seems similar, but more complex, perhaps due to the more complex and stronger, more rapidly evolving fields of ARs compared to other regions (see text). In addition, in 3D the reconnections would be more complex than illustrated here. (Color online)