Projected local-sky regions for comet X/773 B1 over Cobá. The left panel shows the west-southwestern sky at 02:00 LMT; the right panel shows the southeastern sky at 19:00. The pale and orange envelopes show the January 15 projections for directions within Shen and immediately beneath it. Shen is plotted on the Chinese record date, January 17. The Japanese Dai Nihon shi records its visibility on January 20; the account gives no celestial position (J. Chapman et al. 2014). Each smooth envelope encloses 90% of its equally stratified family. The comet symbols trace one representative trajectory; tail lengths are illustrative.