Day 171 of #LMB365 shows Richard Henderson with a model of the membrane protein, bacteriorhodopsin. Richard used high-resolution electron cryo-microscopy, developing new methods for analysing micrographs from tilted specimens, in his landmark paper, published on this day in 1990. The Nobel Committee cited this paper when Richard was awarded the 2017 Nobel Prize for Chemistry. Reference: Richard Henderson et al. Model for the structure of bacteriorhodopsin based on high-resolution electron cryo-microscopy. Journal of Molecular Biology. 213:899-929, 1990