Empirical mass-to-light relation, ( M _☉/ L _☉), derived from WISE 3.4 μm in-band luminosity ( W1 − W2 color (left panel), W2 − W3 color (right panel)) and K _s -derived stellar masses using the Zhu et al. (2010) relation (see also Figure 18). The color error bars represent the formal uncertainties (Table 2) and a 1.5% photometric calibration uncertainty. The linear trend (dashed line) is described by Equations (9) and (10). The dotted line (left panel) represents the ( M _☉/ L _☉) derived for nearby galaxies in the GAMA survey (see the text for details).