American Journal of Astronomy and Astrophysics

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Lifetime Against Sublimation and an Initial Mass Estimate for the Exoplanet α Centauri Bb

Received: 22 August 2015    Accepted: 06 September 2015    Published: 18 September 2015
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Abstract

A two-component, core-mantle, model is developed to estimate the lifetime against destruction via sublimation of close-orbit, terrestrial-mass exoplanets. We specifically focus on the nearest terrestrial exoplanet, α Centauri Bb, since the parent star α Cen B has a reasonably well determined age of 6 ± 1 Gyr. This latter knowledge specifically enables an estimate to be made of the amount of mantle material lost by α Cen Bb since the system formed. Our planet model allows for an iron-core and olivine mantle structure, and it also follows the luminosity evolution of α Cen B. Our results suggest that α Cen Bb had an initial mass of order 2 MEarth, and that of order 0.2 MEarth of mantle material has been lost through sublimation since the planet formed. We additionally consider the fate of any putative planets, moving on circular orbits, interior to α Cen Bb (which has an orbital radius of 0.04 au), and it is found that any Earth mass, or lesser objects, orbiting closer than 0.024 au to α Cen B have lifetimes against destruction by sublimation smaller than 5 billion years.

DOI 10.11648/j.ajaa.20150304.11
Published in American Journal of Astronomy and Astrophysics (Volume 3, Issue 4, July 2015)
Page(s) 70-76
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Exoplanets, α Centauri AB Star System, α Centauri Bb, Sublimation Lifetime

References
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Author Information
  • Campion College, the University of Regina, Regina, SK., Canada; Department of Physics, the University of Regina, Regina, SK., Canada

  • Department of Physics, the University of Regina, Regina, SK., Canada

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  • APA Style

    Martin Beech, Lowell Peltier. (2015). Lifetime Against Sublimation and an Initial Mass Estimate for the Exoplanet α Centauri Bb. American Journal of Astronomy and Astrophysics, 3(4), 70-76. https://doi.org/10.11648/j.ajaa.20150304.11

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    Martin Beech; Lowell Peltier. Lifetime Against Sublimation and an Initial Mass Estimate for the Exoplanet α Centauri Bb. Am. J. Astron. Astrophys. 2015, 3(4), 70-76. doi: 10.11648/j.ajaa.20150304.11

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    AMA Style

    Martin Beech, Lowell Peltier. Lifetime Against Sublimation and an Initial Mass Estimate for the Exoplanet α Centauri Bb. Am J Astron Astrophys. 2015;3(4):70-76. doi: 10.11648/j.ajaa.20150304.11

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  • @article{10.11648/j.ajaa.20150304.11,
      author = {Martin Beech and Lowell Peltier},
      title = {Lifetime Against Sublimation and an Initial Mass Estimate for the Exoplanet α Centauri Bb},
      journal = {American Journal of Astronomy and Astrophysics},
      volume = {3},
      number = {4},
      pages = {70-76},
      doi = {10.11648/j.ajaa.20150304.11},
      url = {https://doi.org/10.11648/j.ajaa.20150304.11},
      eprint = {https://download.sciencepg.com/pdf/10.11648.j.ajaa.20150304.11},
      abstract = {A two-component, core-mantle, model is developed to estimate the lifetime against destruction via sublimation of close-orbit, terrestrial-mass exoplanets. We specifically focus on the nearest terrestrial exoplanet, α Centauri Bb, since the parent star α Cen B has a reasonably well determined age of 6 ± 1 Gyr. This latter knowledge specifically enables an estimate to be made of the amount of mantle material lost by α Cen Bb since the system formed. Our planet model allows for an iron-core and olivine mantle structure, and it also follows the luminosity evolution of α Cen B. Our results suggest that α Cen Bb had an initial mass of order 2 MEarth, and that of order 0.2 MEarth of mantle material has been lost through sublimation since the planet formed. We additionally consider the fate of any putative planets, moving on circular orbits, interior to α Cen Bb (which has an orbital radius of 0.04 au), and it is found that any Earth mass, or lesser objects, orbiting closer than 0.024 au to α Cen B have lifetimes against destruction by sublimation smaller than 5 billion years.},
     year = {2015}
    }
    

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  • TY  - JOUR
    T1  - Lifetime Against Sublimation and an Initial Mass Estimate for the Exoplanet α Centauri Bb
    AU  - Martin Beech
    AU  - Lowell Peltier
    Y1  - 2015/09/18
    PY  - 2015
    N1  - https://doi.org/10.11648/j.ajaa.20150304.11
    DO  - 10.11648/j.ajaa.20150304.11
    T2  - American Journal of Astronomy and Astrophysics
    JF  - American Journal of Astronomy and Astrophysics
    JO  - American Journal of Astronomy and Astrophysics
    SP  - 70
    EP  - 76
    PB  - Science Publishing Group
    SN  - 2376-4686
    UR  - https://doi.org/10.11648/j.ajaa.20150304.11
    AB  - A two-component, core-mantle, model is developed to estimate the lifetime against destruction via sublimation of close-orbit, terrestrial-mass exoplanets. We specifically focus on the nearest terrestrial exoplanet, α Centauri Bb, since the parent star α Cen B has a reasonably well determined age of 6 ± 1 Gyr. This latter knowledge specifically enables an estimate to be made of the amount of mantle material lost by α Cen Bb since the system formed. Our planet model allows for an iron-core and olivine mantle structure, and it also follows the luminosity evolution of α Cen B. Our results suggest that α Cen Bb had an initial mass of order 2 MEarth, and that of order 0.2 MEarth of mantle material has been lost through sublimation since the planet formed. We additionally consider the fate of any putative planets, moving on circular orbits, interior to α Cen Bb (which has an orbital radius of 0.04 au), and it is found that any Earth mass, or lesser objects, orbiting closer than 0.024 au to α Cen B have lifetimes against destruction by sublimation smaller than 5 billion years.
    VL  - 3
    IS  - 4
    ER  - 

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