Top: spatial distributions of nickel, iron, and molecular lines normalized to 1 at photocenter (r = 70 km). Ni (circles) and Fe (crosses) flux ratios were taken as the mean of I(r)/I(r = 70) of the seven Ni and four Fe (7) lines present at all four distances. OH (downward-pointing triangles) and NH (upward-pointing triangles) fluxes and cometocentric distances were digitized from Meier et al. (1998). Bottom: comparison of present Ni and Fe lines (red circles and red crosses, respectively) to the Fe line profile of comet 103P/Hartley 2 (squares, shifted +70 km) reported in Manfroid et al. (2021). A 1/r profile normalized to 1 at r = 70 km is shown in black, with gray contours indicating position uncertainty of the 0″ pointing of Hyakutake. A Haser model of atomic Ni is shown as a dotted red line, assuming daughter and parent scale lengths of 8.9 × 10⁵ km and 200 km, respectively, with red shaded contours showing the uncertainty of the Ni Haser spatial distribution assuming the uncertainty of the photocenter pointing at 0″.