We used the Submillimeter Array to image the SiO maser emission in the v = 1 , J = 5 - 4 transition associated with the peculiar red supergiant VY Canis Majoris .
We identified seven maser components and measured their relative positions and linear polarization properties .
Five of the maser components are coincident to within about 150 mas ( \sim 200 AU at the distance of 1.5 kpc ) ; most of them may originate in the circumstellar envelope at a radius of about 50 mas from the star along with the SiO masers in the lowest rotational transitions .
Our measurements show that two of the maser components may be offset from the inner stellar envelope ( at the 3 \sigma level of significance ) and may be part of a larger bipolar outflow associated with VY CMa identified by Shinnaga et al .
The strongest maser feature at a velocity of 35.9 kms ^ { -1 } has a 60 percent linear polarization , and its polarization direction is aligned with the bipolar axis .
Such a high degree of polarization suggests that maser inversion is due to radiative pumping .
Five of the other maser features have significant linear polarization .