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Expecting the unexpected in the search for extraterrestrial life

Published online by Cambridge University Press:  06 October 2020

Peter Vickers*
Affiliation:
Department of Philosophy, Durham University, UK
*
Author for correspondence: Peter Vickers, E-mail: [email protected]

Abstract

On p. 10 of the 2018 National Academies Exoplanet Science Strategy document (NASEM 2018), ‘Expect the unexpected’ is described as a general principle of the exoplanet field. But for the next 150 pages, this principle is apparently forgotten, as strategy decisions are repeatedly put forward based on our expectations. This paper explores what exactly it might mean to ‘expect the unexpected’, and how this could possibly be achieved by the space science community. An analogy with financial investment strategies is considered, where a balanced portfolio of low/medium/high-risk investments is recommended. Whilst this kind of strategy would certainly be advisable in many scientific contexts (past and present), in certain contexts – especially exploratory science – a significant disanalogy needs to be factored in: financial investors cannot choose low-risk high-reward investments, but sometimes scientists can. The existence of low-risk high-impact projects in cutting-edge space science significantly reduces the warrant for investing in high-risk projects, at least in the short term. However, high-risk proposals need to be fairly judged alongside medium- and low-risk proposals, factoring in both the degree of possible reward and the expected cost of the project. Attitudes towards high-risk high-impact projects within NASA since 2009 are critically analysed.

Type
Research Article
Copyright
Copyright © The Author(s), 2020. Published by Cambridge University Press

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References

Baumeister, RF, Bratslavsky, E, Finkenauer, C and Vohs, KD (2001) Bad is stronger than good. Review of General Psychology 5, 323370.CrossRefGoogle Scholar
Bodman, EHL, Wright, JT, Desch, SJ and Lisse, CM (2018) Inferring the composition of disintegrating planet interiors from dust tails with future James Webb Space Telescope observations. The Astronomical Journal 156, 173, (8pp).10.3847/1538-3881/aadc60CrossRefGoogle Scholar
Boss, A (2009) The Crowded Universe. New York: Basic Books.Google Scholar
Bruner, JS and Postman, L (1949) On the perception of incongruity: a paradigm. Journal of Personality 18, 206223.CrossRefGoogle ScholarPubMed
Cleland, CE (2019a) Moving beyond definitions in the search for extraterrestrial life. Astrobiology 19, 722729.10.1089/ast.2018.1980CrossRefGoogle Scholar
Cleland, CE (2019b) The Quest for a Universal Theory of Life: Searching for Life as We Don't Know It. Cambridge: Cambridge University Press.10.1017/9781139046893CrossRefGoogle Scholar
Dencs, Z and Regály, ZS (2019) Water delivery to the TRAPPIST-1 planets. Monthly Notices of the Royal Astronomical Society 487, 21912199.CrossRefGoogle Scholar
Dong, C, Jin, M, Lingam, M, Airapetian, VS, Ma, Y and van der Holst, B (2018) Atmospheric escape from the TRAPPIST-1 planets and implications for habitability. Proceedings of the National Academy of Sciences of the USA 115, 260.CrossRefGoogle ScholarPubMed
Gillon, M, Triaud, AHMJ, Demory, B, Jehin, E, Agol, E, Deck, KM, Lederer, SM, Wit, J, Burdanov, A, Ingalls, JG, Bolmont, E, Leconte, J, SN, Raymond, Selsis, F, Turbet, M, Barkaoui, K, Burgasser, A, MR, Burleigh, SJ, Carey, Chaushev, A, CM, Copperwheat, Delrez, L, CS, Fernandes, DL, Holdsworth, EJ, Kotze, VV, Grootel, Almleaky, Y, Benkhaldoun, Z, Magain, P and Queloz, D (2017) Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1. Nature 542, 456460.CrossRefGoogle ScholarPubMed
Goldsmith, D (2018) Hidden Worlds and the Quest for Extraterrestrial Life. Cambridge, Mass.: Harvard University Press.10.4159/9780674988897CrossRefGoogle Scholar
Hacking, I (1983) Representing and Intervening. Cambridge, UK: Cambridge University Press.CrossRefGoogle Scholar
Haufe, C (2013) Why do funding agencies favor hypothesis testing? Studies in History and Philosophy of Science 44, 363374.CrossRefGoogle Scholar
Huang, CX, Shporer, A, Dragomir, D, Fausnaugh, M, Levine, AM, Morgan, EH, Nguyen, T, Ricker, GR, Wall, M, Woods, DF and Vanderspek, RK (2018) Expected yields of planet discoveries from the TESS primary and extended missions. Earth and Planetary Astrophysics 1807, 11129.Google Scholar
Institute of Medicine (2007) Rising Above the Gathering Storm: Energizing and Employing America for a Brighter Economic Future. Washington, DC: The National Academies Press.Google Scholar
Joshi, MM and Haberle, RM (2012) Suppression of the water ice and snow albedo feedback on planets orbiting red dwarf stars and the subsequent widening of the habitable zone. Astrobiology 12, 3.CrossRefGoogle ScholarPubMed
Kempton, EM-R, Bean, JL, Louie, DR, Deming, D, Koll, DDB, Mansfield, M, López-Morales, M, MR, Swain, RT, Zellem, Ballard, S, Barclay, T, JK, Barstow, NE, Batalha, TG, Beatty, Berta-Thompson, Z, Birkby, J, LA, Buchhave, Charbonneau, D, NB, Cowan, Crossfield, I, Val-Borro, M, Doyon, R, Dragomir, D, Gaidos, E, Heng, K, Hu, R, Kane, SR, Kreidberg, L, Mallonn, M, CV, Morley, Narita, N, Nascimbeni V, Pallé E, EV, Quintana, Rauscher, E, Seager, S, EL, Shkolnik, DK, Sing, Sozzetti, A, KG, Stassun, JA, Valenti and von Essen, C (2018) A framework for prioritizing the TESS Planetary candidates most amenable to atmospheric characterization. Publications of the Astronomical Society of the Pacific 130, Number 993, 114401, (14pp).CrossRefGoogle Scholar
Kitcher, P (1990) The division of cognitive labor. The Journal of Philosophy 87, 522.10.2307/2026796CrossRefGoogle Scholar
Kuhn, T (1970) The Structure of Scientific Revolutions, 2nd Edn., Chicago: University of Chicago Press.Google Scholar
Luger, R and Barnes, R (2015) Extreme water loss and abiotic O-2 buildup on planets throughout the habitable zones of M dwarfs. Astrobiology 15, 119143.CrossRefGoogle Scholar
Lustig-Yaeger, J, Meadows, VS and Lincowski, AP (2019) The detectability and characterization of the TRAPPIST-1 exoplanet atmospheres with JWST. The Astronomical Journal 158, 27, (28pp).CrossRefGoogle Scholar
Maccrimmon, KR and Wehrung, DA (1988) Taking Risks: The Management of Uncertainty. New York: Macmillan.Google Scholar
Marcy, GW and Butler, RP (1998) Detection of extrasolar giant planets. Annual Review of Astronomy and Astrophysics 36, 5797.10.1146/annurev.astro.36.1.57CrossRefGoogle Scholar
Mayor, M and Queloz, D (1995) A Jupiter-mass companion to a solar-type star. Nature 378, 355359.CrossRefGoogle Scholar
Moores, JE, Atreya, SK, Gough, RV, Martinez, GM, Meslin, PY, CL, Smith, SK, Atreya, PR, Mahaffy, CE, Newman and CR, Webster (2019) Methane seasonal cycle at Gale crater on Mars consistent with regolith adsorption and diffusion. Nature Geoscience 12, 321325.CrossRefGoogle Scholar
NASEM (2017) Review of the Restructured Research and Analysis Programs of NASA's Planetary Science Division (National Academies of Science, Engineering, and Medicine). Washington, DC: The National Academies Press; Available at https://www.nap.edu/catalog/24759/review-of-the-restructured-research-and-analysis-programs-of-nasas-planetary-science-division.Google Scholar
NASEM (2018) Exoplanet Science Strategy (September 2018, National Academies of Science, Engineering, and Medicine). Washington, DC: The National Academies Press; Available at https://sites.nationalacademies.org/SSB/CompletedProjects/SSB_180659.Google Scholar
National Research Council (2010) An Enabling Foundation for NASA's Earth and Space Science Missions. Washington, DC: The National Academies Press.Google Scholar
Oreskes, N and Conway, EM (2010) Merchants of Doubt. New York, USA: Bloomsbury Press.Google ScholarPubMed
Psillos, S (1999) Scientific Realism: How Science Tracks Truth. London, UK: Routledge.Google Scholar
Schingler, R, Marshall, W, MacDonald, A, Lupisella, M and Lewis, B (2009) ROSI – Return on Science Investment: A System for Mission Evaluation Based on Maximizing Science, a White Paper in Support of the Planetary Science Decadal Survey 2013–2022, a Report of the National Research Council. Washington, DC: National Academies Press.Google Scholar
Schwieterman, EW, Meadows, VS, Domagal-Goldman, SD, Deming, D, Arney, GN, Luger, R, Harman, CE, Misra, A and Barnes, R (2016) Identifying planetary biosignature impostors: spectral features of CO and O4 resulting from abiotic O2/O3 production. Astrophysical Journal Letters 819, L13.10.3847/2041-8205/819/1/L13CrossRefGoogle ScholarPubMed
Simons, DJ and Chabris, CF (1999) Gorillas in our midst: sustained inattentional blindness for dynamic events. Perception 28, 10591074.CrossRefGoogle ScholarPubMed
Stanford, K (2019) Unconceived alternatives and conservatism in science: the impact of professionalization, peer-review, and Big Science. Synthese 196, 39153932.10.1007/s11229-015-0856-4CrossRefGoogle Scholar
Strevens, M (2003) The role of the priority rule in science. The Journal of Philosophy 100, 5579.10.5840/jphil2003100224CrossRefGoogle Scholar
Walker, GAH (2003) Seeking other solar systems. Chapter Twenty In Garwin, L and Lincoln, T (eds), A Century of Nature: Twenty-One Discoveries that Changed Science and the World. Chicago: University of Chicago Press, pp. 313332.CrossRefGoogle Scholar
Walker, GAH, Walker, AR, Irwin, AW, Larson, AM, Yang, SLS and Richardson, DC (1995) A search for Jupiter-Mass companions to nearby stars. Icarus 116, 359375.10.1006/icar.1995.1130CrossRefGoogle Scholar
Weisberg, M and Muldoon, R (2009) Epistemic landscapes and the division of cognitive labor. Philosophy of Science 76, 225252.CrossRefGoogle Scholar
Zollman, KJS (2010) The epistemic benefit of transient diversity. Erkenntnis 72, 1735.CrossRefGoogle Scholar