Red Dwarfs pp 285-312 | Cite as

The Failure of Early Optimism

  • David S. Stevenson


When the first edition of this book was written there were only two plausible candidate systems that might host planets in their stars’ habitable zone, Gliese 581 and Gliese 667C. Both systems hosted a number of super-terrans, whose numbers varied often by the month as radial velocity data was interpreted, reinterpreted, discarded, recovered—only for vexing to continue. Obviously, like many of the authors of the papers upon which the book was centered, hyperbole tended to replace considered thought as the possibility of fame and further grants beckoned. The Gliese 581 system was a source of particular ire as rival groups made claims for the existence of planet 581g, which was at the time the best candidate for an Earth-like world—albeit a tidally locked one. This chapter rounds up some of the acrimony and resolution that surrounded the dissection of these star systems and discusses, in the light of the earlier chapters, just how habitable these worlds really were.


Barnard b

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Gliese 832c

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Luyten b (GJ 273b)

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LHS 1140

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Proxima b

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  2. Feng, F., & Jones, H. R. A. (2018). Was Proxima captured by alpha Centauri A and B? Monthly Notices of the Royal Astronomical Society, 473(3), 3185–3189. Scholar
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  1. Bonfils, X., Astudillo-Defru, N., Díaz, R., Almenara, J.-M., Forveille, T., Bouchy, F., Delfosse, X., Lovis, C., Mayor, M., Murgas, F., Pepe, F., Santos, N. C., Ségransan, D., Udry, S., & Wünsche, A. (2016). A temperate exo-Earth around a quiet M dwarf at 3.4 parsecs. Astronomy & Astrophysics, 613, 9. Scholar

Teegarden b and c

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  1. LePage, A. (2017). I also draw the reader’s attention to an article by Andrew LePage at:
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Gliese 581d

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • David S. Stevenson
    • 1
  1. 1.SherwoodUK

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