Extended Data Fig. 7: The optical and NIR light curves of GRB 211211A have similar luminosities and decay rates compared with past kilonovae and kilonova candidates.

The rest-frame i-band (a) and K-band (b) light curves of GRB 211211A (purple diamonds), GW170817/AT 2017gfo (grey points, ref. ²⁰ and references therein) and previous short GRB kilonova upper limits (yellow triangles) and detections (yellow circles^{105,147,150,151}). As there are no other rest-frame K-band kilonova light curves beyond AT 2017gfo, we plot rest-frame J-band and H-band short GRB kilonova observations for comparison (open circles and triangles^{105,147,150,151,152,153,154,155}). At z = 0.076, the K-band counterpart to GRB 211211A is of similar luminosity to AT 2017gfo and fades on similar timescales.