Proxima’s orbit around α Centauri

  title={Proxima’s orbit around $\alpha$ Centauri},
  author={Pierre Kervella and F. Th{\'e}venin and Christophe Lovis},
  journal={Astronomy and Astrophysics},
Proxima and α Centauri AB have almost identical distances and proper motions with respect to the Sun. Although the probability of such similar parameters is, in principle, very low, the question as to whether they actually form a single gravitationally bound triple system has been open since the discovery of Proxima one century ago. Owing to HARPS high-precision absolute radial velocity measurements and the recent revision of the parameters of the α Cen pair, we show that Proxima and α Cen are… 

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