Pinwheel Nebula around WR 98a

@article{Monnier1999PinwheelNA,
  title={Pinwheel Nebula around WR 98a},
  author={John D. Monnier and Peter G. Tuthill and William C. Danchi},
  journal={The Astrophysical Journal Letters},
  year={1999},
  volume={525},
  pages={L97 - L100}
}
We present the first near-infrared images of the dusty Wolf-Rayet star WR 98a. Aperture-masking interferometry has been utilized to recover images at the diffraction limit of the Keck I telescope, ≲50 mas at 2.2 μm. Multiepoch observations spanning about 1 yr have resolved the dust shell into a "pinwheel" nebula, the second example of a new class of dust shell first discovered around WR 104 by Tuthill, Monnier, & Danchi. Interpreting the collimated dust outflow in terms of an interacting winds… 

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