Perseus cluster maps. Shown is the 0.5 to 2 keV X-ray surface brightness and contours (log cts s⁻¹ per 1.6 arcsec pixel; top left), fractional difference of surface brightness to radial average (top right), temperature (keV; centre left), metallicity (Z_⊙; centre right), velocity relative to the cluster value in H16 (km s⁻¹; bottom left) and 1σ statistical uncertainty on velocity (km s⁻¹; bottom right). Maps were created by a moving 3:1 elliptical region (rotated to lie tangentially to the nucleus) containing ∼700 Fe-K counts (see example ellipses in velocity error plot). The pixels are not statistically independent.