The asymmetric nebula surrounding the extreme red supergiant VY Canis Majoris

We present HST/WFPC2 images plus ground-based infrared images and photometr y of the very luminous OH/IR star VY Canis Majoris. Our WFPC2 data show a c omplex distribution of knots and filamentary arcs in the asymmetric reflect ion nebula around the obscured central star. The reflection arcs may result from multiple, asymmetric ejection episodes due to localized events on VY CMa's surface. Such events probably involve magnetic fields and convection, by analogy with solar activity. Surface photometry indicates that the star may have experienced enhanced mass loss over the past 1000 yr. We also dem onstrate that the apparent asymmetry of the nebula results from a combinati on of high extinction and backscattering by dust grains. Thermal-infrared i mages reveal a more symmetric distribution, elongated along a nearly east-w est direction. VY CMa probably has a flattened disklike distribution of dus t with a northeast-southwest polar axis and may be experiencing activity an alogous to solar prominences. The presence of an axis of symmetry raises in teresting questions for a star the size of Saturn's orbit. Magnetic fields and surface activity may play an important role in VY CMa's mass-loss histo ry.