Large convection cells as the source of Betelgeuse's extended atmosphere

  title={Large convection cells as the source of Betelgeuse's extended atmosphere},
  author={Jeremy Lim and Christopher L. Carilli and Stephen M. White and Anthony J. Beasley and Ralph G. Marson},
Supergiant stars such as Betelgeuse have very extended atmospheres, the properties of which are poorly understood. Alfvén waves, acoustic waves,, and radial pulsations have all been suggested as likely mechanisms for elevating these atmospheres and driving the massive outflows of gas seen in these stars: such mechanisms would heat the atmosphere from below, and there are indeed observations showing that Betelgeuse's extended atmosphere is hotter than the underlying photosphere,. Here we report… 
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