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HD 20781 is a star which is part of a wide binary system with HD 20782. Both stars possess their own planetary systems in S type orbits. This is the first time that planets have been found in both components of a wide binary system.
Mayor, M. Marmier,M. Lovis,C. Udry,S. Ségransan,D. Pepe,F. Benz,W. Bertaux,J.-L. Bouchy,F. Dumusque, G. Curto,Lo Mordasini,C. Queloz,D. Santos,N. C.; et al. (2011). "The HARPS search for southern extra-solar planets XXXIV. Occurrence, mass distribution and orbital properties of super-Earths and Neptune-mass planets". arXiv:1109.2497 . {{cite arXiv}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
Schneider, J. "Notes for star HD 20781". The Extrasolar Planets Encyclopaedia. Retrieved 2011-09-12.