The bending of light by a gravitational body was predicted by Albert Einstein in 1912, a few years before the publication of general relativity in 1916 (Renn et al. 1997). The ring effect was first mentioned in the academic literature by Orest Khvolson in a short article in 1924, in which he mentioned the “halo effect” of gravitation when the source, lens, and observer are in near-perfect alignment. Einstein remarked upon this effect in 1936 in a paper prompted by a letter by a Czech engineer, R W Mandl [http://www.slac.stanford.edu/pubs/beamline/31/1/31-1-maurer.pdf], but stated