The layer of nickel (Ni) atoms in the upper mesosphere and lower thermosphere (MLT) as well the layers of other metals (Fe, Na, Mg, Ca, and K) produced by meteoric ablation provide a unique means of observing the physics and chemistry of the atmosphere between 75 and 110 km (Plane, 2003;Plane et al., 2015). Although the Ni layer was only observed for the first time in 2012 (Collins et al., 2015), much progress in understanding the characteristic features of the layer has been made in the past 5 years. This has been achieved through a combination of further observations (

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