A mean profile of molecular emission observed with the SMA (black) in V838 Mon is compared to the SiO v = 1 J = 2–1 spectrum and an optical absorption profile of Ca I at 6573 Å. The profile of molecular emission is a mean of normalized unblended lines of CO and of ^28,29SiO observed in 2016. The maser emission near 86 GHz was observed with the IRAM 30 m telescope in 2015. The maser defines the systemic velocity of the star which is marked with a vertical dashed line. The absorption profile of Ca I was extracted from a spectrum obtained in 2012 with VLT/UVES; it was normalized and shifted by –1. Its deep double absorption trough represents circumstellar absorption on the line of sight toward the star. A wavy pattern in the optical spectrum is caused by molecular absorption features, mainly by electronic bands of TiO.