Os tardígrados (ursos-d'água) sobreviverão ao fim do mundo que nós conhecemos

sexta-feira, julho 21, 2017

The Resilience of Life to Astrophysical Events

David Sloan, Rafael Alves Batista & Abraham Loeb

Scientific Reports 7, Article number: 5419 (2017)


Download Citation

Astrobiology Exoplanets

Received: 18 January 2017 Accepted: 05 June 2017 

Published online: 14 July 2017

Source/Fonte: Science News

Abstract

Much attention has been given in the literature to the effects of astrophysical events on human and land-based life. However, little has been discussed on the resilience of life itself. Here we instead explore the statistics of events that completely sterilise an Earth-like planet with planet radii in the range 0.5–1.5R⊕ and temperatures of ∼300 K, eradicating all forms of life. We consider the relative likelihood of complete global sterilisation events from three astrophysical sources – supernovae, gamma-ray bursts, large asteroid impacts, and passing-by stars. To assess such probabilities we consider what cataclysmic event could lead to the annihilation of not just human life, but also extremophiles, through the boiling of all water in Earth’s oceans. Surprisingly we find that although human life is somewhat fragile to nearby events, the resilience of Ecdysozoa such as Milnesium tardigradum renders global sterilisation an unlikely event.

Acknowledgements

D.S. and R.A.B. acknowledge the financial support from the John Templeton Foundation.

Author information

Affiliations

Department of Physics - Astrophysics, University of Oxford, Denys Wilkinson Building, Keble Road, OX1 3RH, Oxford, UK

David Sloan & Rafael Alves Batista

Astronomy Department, Harvard University, 60 Garden Street, Cambridge, MA, 02138, USA

Abraham Loeb

Contributions

The idea of this work was conceived by A.L., D.S. and R.A.B. contributed equally to the analysis of results, with some input from A.L. D.S. did most of the writing, with aid of R.A.B. Figures were produced by R.A.B., A.L. was responsible for the scope and accuracy checking of the analysis.

Competing Interests

The authors declare that they have no competing interests.

Corresponding author

Correspondence to Rafael Alves Batista.

FREE PDF GRATIS: Science Reports