Left: SiO ﹩J=1{\mbox{--}} 0﹩, ﹩\nu =2﹩ maser in R Aqr on 2006 September 16. Color indicates velocity, red = −16.0 km s⁻¹, blue = −26.7 km s⁻¹, and the displayed intensity is proportional to the square root of the measured intensity. The yellow circle has the diameter of the H₂O shell from Table 2 (26.7 mas) and is concentric with the maser ring, which is assumed to be approximately centered on the star. Right: Same as left, but for ﹩J=1{\mbox{--}} 0﹩, ﹩\nu =1﹩ transition.