Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-25T14:53:37.080Z Has data issue: false hasContentIssue false

Exoplanet transits as the foundation of an interstellar communications network

Published online by Cambridge University Press:  12 March 2018

Duncan H. Forgan*
Affiliation:
SUPA, School of Physics and Astronomy, University of St Andrews, UK St Andrews Centre for Exoplanet Science, UK

Abstract

Two fundamental problems for extraterrestrial intelligences (ETIs) attempting to establish interstellar communication are timing and energy consumption. Humanity's study of exoplanets via their transit across the host star highlights a means of solving both problems. An ETI ‘A’ can communicate with ETI ‘B’ if B is observing transiting planets in A's star system, either by building structures to produce artificial transits observable by B, or by emitting signals at B during transit, at significantly lower energy consumption than typical electromagnetic transmission schemes. This can produce a network of interconnected civilizations, establishing contact via observing each other's transits. Assuming that civilizations reside in a Galactic Habitable Zone (GHZ), I conduct Monte Carlo Realization simulations of the establishment and growth of this network, and analyse its properties in the context of graph theory. I find that at any instant, only a few civilizations are correctly aligned to communicate via transits. However, we should expect the true network to be cumulative, where a ‘handshake’ connection at any time guarantees connection in the future via e.g. electromagnetic signals. In all our simulations, the cumulative network connects all civilizations together in a complete network. If civilizations share knowledge of their network connections, the network can be fully complete on timescales of order a hundred thousand years. Once established, this network can connect any two civilizations either directly, or via intermediate civilizations, with a path much less than the dimensions of the GHZ.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2018 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Arnold, L. (2013). Int. J. Astrobiol. 12, 212.Google Scholar
Arnold, L.F.A. (2005). Astrophys. J, 627, 534.Google Scholar
Benford, G., Benford, J. & Benford, D. (2010a). Astrobiology 10, 491.Google Scholar
Benford, J., Benford, G. & Benford, D. (2010b). Astrobiology 10, 475.Google Scholar
Bhattacharjee, P., Chaudhury, S. & Kundu, S. (2014). Astrophys. J. 785, 63.Google Scholar
Bodman, E.H.L. & Quillen, A. (2016). Astrophys. J. 819, L34.Google Scholar
Boyajian, T.S. et al. (2016). Mon. Not. R. Astron. Soc. 457, 3988.Google Scholar
Conn Henry, R., Kilston, S. & Shostak, S. (2008). Bull. Am. Astron. Soc. 40, 194.Google Scholar
Dijkstra, E.W. (1959). Numer. Math. 1, 269.Google Scholar
Doyle, L.R. et al. (2011). Science 333, 1602.Google Scholar
Duquennoy, A. & Mayor, M. (1991). Astron. Astrophys. 248, 485.Google Scholar
Filippova, L.N. & Strelnitskij, V.S. (1988). Astron. Tsirk. 1531, 31.Google Scholar
Forgan, D. & Nichol, R. (2010). Int. J. Astrobiol. 10, 77.Google Scholar
Forgan, D., Dayal, P., Cockell, C. & Libeskind, N. (2017). Int. J. Astrobiol. 16, 60.Google Scholar
Forgan, D.H. (2013). J. Br. Interplanet. Soc. 66, 144.Google Scholar
Forgan, D.H. (2014). J. Br. Interplanet. Soc. 67, 232.Google Scholar
Forgan, D.H. (2016). Int. J. Astrobiol. 16, 349354.Google Scholar
Gaudi, B.S. (2011). Exoplanets, pp. 79–110.Google Scholar
Gowanlock, M.G., Patton, D.R. & McConnell, S.M. (2011). Astrobiology 11, 855.Google Scholar
Haqq-Misra, J., Kopparapu, R.K. & Wolf, E.T. (2017). Int. J. Astrobiol. 17, 7786.Google Scholar
Heller, R. & Pudritz, R.E. (2016). Astrobiology 16, 259.Google Scholar
Isaacson, H. et al. (2017). eprint arXiv:1701.06227.Google Scholar
Jarník, V. (1930). Práce moravské prírodovědecké společnosti 6, 57.Google Scholar
Kipping, D.M. & Teachey, A. (2016). MNRAS 459, 1233.Google Scholar
Lineweaver, C.H., Fenner, Y. & Gibson, B.K. (2004). Science 303, 59.Google Scholar
Lovis, C. & Fischer, D. (2011). Exoplanets, pp. 2754.Google Scholar
Martin, D.V. & Triaud, A.H.M.J. (2015). Mon. Not. R. Astron. Soc. 449, 781.Google Scholar
Metzger, B.D., Shen, K.J. & Stone, N.C. (2016). eprint arXiv:1612.07332.Google Scholar
Ostlie, D. & Carroll, B. (1996). In An Introduction to Modern Stellar Astrophysics, ed. Ostlie, D. & Carroll, B., Pearson Education. Chapter 24 The Milky Way Galaxy, pp. 885–952. Addison-Wesley, Boston, MA and University of Michigan, Ann Arbor, Michigan.Google Scholar
Prim, R.C. (1957). Bell Syst. Tech. J. 36, 1389.Google Scholar
Raghavan, D. et al. (2010). Astrophys. J. Supl. Ser. 190, 1.Google Scholar
Tarter, J. (2007). In Planets and Life – The Emerging Science of Astrobiology, ed. Sullivan, W.T. III & Baross, T., Searching for extraterrestrial intelligence, pp. 513536. Cambridge University Press, Cambridge.Google Scholar
Traub, W.A. & Oppenheimer, B.R. (2010). Exoplanets 372, 111.Google Scholar
Vukotić, B., Steinhauser, D., Martinez-Aviles, G., Ćirković, M.M., Micic, M. & Schindler, S. (2016). Mon. Not. R. Astron. Soc. 459, 3512.Google Scholar
Winn, J.N. (2011). In Exoplanets, ed. Seager, S., exoplanet transits and occultations, in exoplanets, pp. 5578. University of Arizona Press, Tucson.Google Scholar
Wright, J.T. & Sigurdsson, S. (2016). ApJ 829, L3.Google Scholar
Wright, J.T., Cartier, K.M.S., Zhao, M., Jontof-Hutter, D. & Ford, E.B. (2015). Astrophys. J. 816, 17.Google Scholar
Zeng, W. & Church, R.L. (2009). Int. J. Geogr. Inf. Sci. 23, 531.Google Scholar