1998/10/01 by J. D. Monnier, John D. Monnier, Peter Tuthill +8 · 7 citations
Physics and Astronomy · #Adaptive optics #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Star Formation Studies #Circumstellar dust #Cosmic dust #Galaxy #Integral field spectrograph #Luminosity #Nebula #Physics #Red supergiant #Rotation period #Spectral line #Spectrograph #Stars #Stellar, planetary, and galactic studies #Supergiant #Telescope #astro-ph
paper · pdf · doi:10.1086/306761
25 pages total with 1 table and 5 figures. Accepted by Astrophysical Journal (to appear in February 1999)
arxiv created 1998/10/01 · openalex publication_date 1999/02/10 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
We present new observations of the red supergiant VY CMa at 1.25, 1.65, 2.26, 3.08, and 4.8 μm. Two complementary observational techniques were utilized: nonredundant aperture masking on the 10 m Keck I telescope, yielding images of the innermost regions at unprecedented resolution, and adaptive optics imaging on the ESO 3.6 m telescope at La Silla, attaining an extremely high (~10 5 ) peak-to-noise dynamic range over a wide field. For the first time the inner dust shell has been resolved in the near-infrared to reveal a one-sided extension of circumstellar emission within 0 1 (~15 R * ) of the star. The line-of-sight optical depths of the circumstellar dust shell at 1.65, 2.26, and 3.08 μm have been estimated to be 1.86±0.42, 0.85±0.20, and 0.44±0.11, respectively. These new results allow the bolometric luminosity of VY CMa to be estimated independent of the dust shell geometry, yielding L * ≈ 2 × 10 5 L ☉ . A variety of dust condensations, including a large scattering plume and a bow-shaped dust feature, were observed in the faint, extended nebula up to 4'' from the central source. While the origin of the nebulous plume remains uncertain, a geometrical model is developed assuming the plume is produced by radially driven dust grains forming at a rotating flow insertion point with a rotational period between 1200 and 4200 yr, which is perhaps the stellar rotational period or the orbital period of an unseen companion.