Advertisement

The Detectability of Earth’s Biosignatures Across Time

  • Enric Pallé
Living reference work entry

Abstract

Over the past two decades, enormous advances in the detection of exoplanets have taken place. Currently, we have discovered hundreds of Earth-sized planets, several of them within the habitable zone of their star. In the coming years, the efforts will concentrate in the characterization of these planets and their atmospheres to try to detect the presence of biosignatures. However, even if we discovered a second Earth, it is very unlikely that it would present a stage of evolution similar to the present-day Earth. Our planet has been far from static since its formation about 4.5 Ga ago; on the contrary, during this time, it has undergone multiple changes in its atmospheric composition, its temperature structure, its continental distribution, and even changes in the forms of life that inhabit it. All these changes have affected the global properties of Earth as seen from an astronomical distance. Thus, it is of interest not only to characterize the observables of the Earth as it is today but also at different epochs. Here we review the detectability of the Earth’s globally averaged properties over time. This includes atmospheric composition and biosignatures and surface properties that can be interpreted as signs of habitability (bioclues). The resulting picture is that truly unambiguous biosignatures are only detectable for about 1/4 of the Earth’s history. For the rest of the time, we rely on detectable bioclues that can only establish an statistical likelihood for the presence of life on a given planet.

Notes

Acknowledgements

This work is partly financed by the Spanish Ministry of Economics and Competitiveness through projects ESP2014-57495-C2-1-R and ESP2016-80435-C2-2-R of the Spanish Secretary of State for R&D&i (MINECO).

References

  1. Abe Y, Matsui T (1988) Evolution of an impact-generated H2O–CO2 atmosphere and formation of a hot proto-ocean on Earth. J Atmos Sci 45:3081–3101Google Scholar
  2. Abramov O, Mojzsis SJ (2009) Microbial habitability of the Hadean Earth during the late heavy bombardment. Nature 459:419–422ADSCrossRefGoogle Scholar
  3. Ackerman AS, Marley MS (2001) Precipitating condensation clouds in substellar atmospheres. ApJ 556:872–884Google Scholar
  4. Albani AE, Bengtson S, Canfield DE et al (2010) Large colonial organisms with coordinated growth in oxygenated environments 2.1 Gyr ago. Nature 466:100–104Google Scholar
  5. Anglada-Escudé G, Tuomi M, Gerlach E et al (2013) A dynamically-packed planetary system around GJ 667C with three super-Earths in its habitable zone. A&A 556:A126ADSCrossRefGoogle Scholar
  6. Anglada-Escudé G, Amado PJ, Barnes J et al (2016) A terrestrial planet candidate in a temperate orbit around Proxima Centauri. Nature 536:437–440ADSCrossRefGoogle Scholar
  7. Arney G, Domagal-Goldman SD, Meadows VS et al (2016) The pale orange dot: the spectrum and habitability of hazy archean Earth. Astrobiology 16:873–899ADSCrossRefGoogle Scholar
  8. Arnold L, Gillet S, Lardière O, Riaud P, Schneider J (2002) A test for the search for life on extrasolar planets. Looking for the terrestrial vegetation signature in the Earthshine spectrum. A&A 392:231–237Google Scholar
  9. Bahcall JN, Pinsonneault MH Basu S (2001) Solar models: current epoch and time dependences, neutrinos, and helioseismological properties. ApJ 555:990–1012ADSCrossRefGoogle Scholar
  10. Barclay T, Burke CJ, Howell SB et al (2013) A super-earth-sized planet orbiting in or near the habitable zone around a sun-like star. ApJ 768:101ADSCrossRefGoogle Scholar
  11. Borucki WJ, Koch DG, Batalha N et al (2012) Kepler-22b: a 2.4 Earth-radius planet in the habitable zone of a Sun-like Star. ApJ 745:120Google Scholar
  12. Borucki WJ, Agol E, Fressin F et al (2013) Kepler-62: a five-planet system with planets of 1.4 and 1.6 earth radii in the habitable zone. Science 340:587–590Google Scholar
  13. Bowring SA, Williams IS (1999) Priscoan (4.00–4.03 Ga) orthogneisses from northwestern Canada. Contrib Mineral Petrol 134:3–16Google Scholar
  14. Buick R (2010) Early life: ancient acritarchs. Nature 463:885–886ADSCrossRefGoogle Scholar
  15. Cassan A, Kubas D, Beaulieu JP et al (2012) One or more bound planets per Milky Way star from microlensing observations. Nature 481:167–169Google Scholar
  16. Charbonneau D, Berta ZK, Irwin J et al (2009) A super-Earth transiting a nearby low-mass star. Nature 462:891–894ADSCrossRefGoogle Scholar
  17. Charnay B, Forget F, Wordsworth R et al (2013) Exploring the faint young Sun problem and the possible climates of the Archean Earth with a 3-D GCM. J Geophys Res (Atmos) 118:10Google Scholar
  18. Cowan NB, Robinson T, Livengood TA et al (2011) Rotational variability of earth’s polar regions: implications for detecting snowball planets. ApJ 731:76Google Scholar
  19. Crow CA, McFadden LA, Robinson T et al (2011) Views from EPOXI: colors in our solar system as an analog for extrasolar planets. ApJ 729:130ADSCrossRefGoogle Scholar
  20. Des Marais DJ, Harwit MO, Jucks KW et al (2002) Remote sensing of planetary properties and biosignatures on extrasolar terrestrial planets. Astrobiology 2:153–181Google Scholar
  21. Domagal-Goldman SD, Meadows VS, Claire MW, Kasting JF (2011) Using biogenic sulfur gases as remotely detectable biosignatures on anoxic planets. Astrobiology 11:419–441ADSCrossRefGoogle Scholar
  22. Ford EB, Seager S, Turner EL (2001) Characterization of extrasolar terrestrial planets from diurnal photometric variability. Nature 412:885–887ADSCrossRefGoogle Scholar
  23. Fressin F, Torres G, Rowe JF et al (2012) Two Earth-sized planets orbiting Kepler-20. Nature 482:195–198ADSCrossRefGoogle Scholar
  24. Fressin F, Torres G, Charbonneau D et al (2013) The false positive rate of Kepler and the occurrence of planets. ApJ 766:81ADSCrossRefGoogle Scholar
  25. Fujii Y, Kawahara H (2012) Mapping Earth analogs from photometric variability: spin-orbit tomography for planets in inclined orbits. ApJ 755:101ADSCrossRefGoogle Scholar
  26. Fujii Y, Turner EL, Suto Y (2013) Variability of water and oxygen absorption bands in the disk-integrated spectra of Earth. ApJ 765:76Google Scholar
  27. Furukawa Y, Sekine T, Oba M, Kakegawa T, Nakazawa H (2009) Biomolecule formation by oceanic impacts on early Earth. Nat Geosci 2:62–66Google Scholar
  28. Gebauer S, Grenfell JL, Stock JW et al (2017) Evolution of Earth-like extrasolar planetary atmospheres: assessing the atmospheres and biospheres of early Earth analog planets with a coupled atmosphere biogeochemical model. Astrobiology 17:27–54ADSCrossRefGoogle Scholar
  29. Gilliland RL, Marcy GW, Rowe JF et al (2013) Kepler-68: three planets, one with a density between that of Earth and ice giants. ApJ 766:40ADSCrossRefGoogle Scholar
  30. Gillon M, Triaud AHMJ, Demory BO et al (2017) Seven temperate terrestrial planets around the nearby ultracool dwarf star TRAPPIST-1. Nature 542:456–460ADSCrossRefGoogle Scholar
  31. Gomes R, Levison HF, Tsiganis K, Morbidelli A (2005) Origin of the cataclysmic late heavy bombardment period of the terrestrial planets. Nature 435:466–469Google Scholar
  32. Gough DO (1981) Solar interior structure and luminosity variations. Sol Phys 74:21–34ADSCrossRefGoogle Scholar
  33. Govindasamy B, Caldeira K (2000) Geoengineering Earth’s radiation balance to mitigate CO2-induced climate change. Geophys Res Lett 27:2141–2144ADSCrossRefGoogle Scholar
  34. Hamdani S, Arnold L, Foellmi C et al (2006) Biomarkers in disk-averaged near-UV to near-IR Earth spectra using Earthshine observations. A&A 460:617–624Google Scholar
  35. Haqq-Misra JD, Domagal-Goldman SD, Kasting PJ, Kasting JF (2008) A revised, hazy methane greenhouse for the archean Earth. Astrobiology 8:1127–1137ADSCrossRefGoogle Scholar
  36. Hegde S, Kaltenegger L (2013) Colors of extreme exo-Earth environments. Astrobiology 13:47–56Google Scholar
  37. Hoffman PF, Kaufman AJ, Halverson GP, Schrag DP (1998) A neoproterozoic snowball Earth. Science 281:1342ADSCrossRefGoogle Scholar
  38. Kaltenegger L, Traub WA, Jucks KW (2007) Spectral evolution of an Earth-like planet. ApJ 658:598–616ADSCrossRefGoogle Scholar
  39. Kamber BS (2015) The evolving nature of terrestrial crust from the Hadean, through the Archaean, into the Proterozoic. Precambrian Res 258:48–82ADSCrossRefGoogle Scholar
  40. Kasting JF (1993) Earth’s early atmosphere. Science 259:920–926ADSCrossRefGoogle Scholar
  41. Kasting JF, Brown LL (1998) Methanogenesis and the climates of early Earth and Mars. In: Celnikier LM, Trân Thanh Vân J (eds) Planetary systems: the long view, p 443. http://adsabs.harvard.edu/abs/1998pslv.conf..443K
  42. Kawahara H, Fujii Y (2010) Global mapping of Earth-like exoplanets from scattered light curves. ApJ 720:1333–1350ADSCrossRefGoogle Scholar
  43. Kawahara H, Fujii Y (2011) Mapping clouds and terrain of earth-like planets from photometric variability: demonstration with planets in face-on orbits. ApJ 739:L62ADSCrossRefGoogle Scholar
  44. Kiang NY, Segura A, Tinetti G et al (2007a) Spectral signatures of photosynthesis. II. Coevolution with other stars and the atmosphere on extrasolar worlds. Astrobiology 7:252–274ADSCrossRefGoogle Scholar
  45. Kiang NY, Siefert J, Govindjee, Blankenship RE (2007b) Spectral signatures of photosynthesis. I. Review of Earth organisms. Astrobiology 7:222–251ADSCrossRefGoogle Scholar
  46. Kiehl JT, Dickinson RE (1987) A study of the radiative effects of enhanced atmospheric CO_2 and CH_4 on early Earth surface temperatures. J Geophys Res 92:2991–2998Google Scholar
  47. Krissansen-Totton J, Bergsman DS, Catling DC (2016) On detecting biospheres from chemical thermodynamic disequilibrium in planetary atmospheres. Astrobiology 16:39–67ADSCrossRefGoogle Scholar
  48. Lingam M, Loeb A (2017) Natural and artificial spectral edges in exoplanets. ArXiv e-printsADSCrossRefGoogle Scholar
  49. Lovelock JE (1975) Thermodynamics and the recognition of alien biospheres. Proc R Soc Lond Ser B 189:167–180Google Scholar
  50. Miles-Páez PA, Pallé E, Zapatero Osorio MR (2014) Simultaneous optical and near-infrared linear spectropolarimetry of the earthshine. A&A 562:L5ADSCrossRefGoogle Scholar
  51. Mojzsis SJ, Arrhenius G, McKeegan KD et al (1996) Evidence for life on Earth before 3,800 million years ago. Nature 384:55–59ADSCrossRefGoogle Scholar
  52. Mojzsis SJ, Harrison TM, Pidgeon RT (2001) Oxygen-isotope evidence from ancient zircons for liquid water at the Earth’s surface 4300 Myr ago. Nature 409:178–181Google Scholar
  53. Montañés-Rodríguez P, Pallé E, Goode PR, Martín-Torres FJ (2006) Vegetation signature in the observed globally integrated spectrum of earth considering simultaneous cloud data: applications for extrasolar planets. ApJ 651:544–552Google Scholar
  54. Muirhead PS, Johnson JA, Apps K et al (2012) Characterizing the cool KOIs. III. KOI 961: a small star with large proper motion and three small planets. ApJ 747:144Google Scholar
  55. Olson J (2006) Photosynthesis in the archean era. Photosynth Res 88(2):109–117CrossRefGoogle Scholar
  56. O’Malley-James JT, Greaves JS, Raven JA, Cockell CS (2013) Swansong biospheres: refuges for life and novel microbial biospheres on terrestrial planets near the end of their habitable lifetimes. Int J Astrobiol 12:99–112ADSCrossRefGoogle Scholar
  57. O’Malley-James JT, Cockell CS, Greaves JS, Raven JA (2014) Swansong biospheres II: the final signs of life on terrestrial planets near the end of their habitable lifetimes. Int J Astrobiol 13:229–243ADSCrossRefGoogle Scholar
  58. Pallé E, Goode PR, Yurchyshyn V et al (2003) Earthshine and the Earth’s albedo: 2. Observations and simulations over 3 years. J Geophys Res (Atmos) 108:4710Google Scholar
  59. Pallé E, Goode PR, Montanes-Rodriguez P, Koonin SE (2004) Changes in Earth’s reflectance over the past two decades. Science 304:1299–1301ADSCrossRefGoogle Scholar
  60. Pallé E, Ford EB, Seager S, Montañés-Rodríguez P, Vazquez M (2008) Identifying the rotation rate and the presence of dynamic weather on extrasolar Earth-like planets from photometric observations. ApJ 676:1319–1329ADSCrossRefGoogle Scholar
  61. Pallé E, Zapatero Osorio MR, Barrena R, Montañés-Rodríguez P, Martín EL (2009) Earth’s transmission spectrum from lunar eclipse observations. Nature 459:814–816ADSCrossRefGoogle Scholar
  62. Parenteau MN, Kiang NY, Blankenship RE, Sanromá E, Palle Bago, E, Hoehler TM, Pierson BK, Meadows VS (2015) Global surface photosynthetic biosignatures prior to the rise of Oxygen. In: AGU fall meeting abstracts, p P32B–05. http://adsabs.harvard.edu/abs/2015AGUFM.P32B..05P
  63. Pepe F, Lovis C, Ségransan D et al (2011) The HARPS search for Earth-like planets in the habitable zone. I. Very low-mass planets around <ASTROBJ>HD 20794</ASTROBJ>, <ASTROBJ>HD 85512</ASTROBJ>, and <ASTROBJ>HD 192310</ASTROBJ>. A&A 534:A58Google Scholar
  64. Pinto JP, Gladstone GR, Yung YL (1980) Photochemical production of formaldehyde in earth’s primitive atmosphere. Science 210:183–185ADSCrossRefGoogle Scholar
  65. Qiu J, Goode PR, Pallé E et al (2003) Earthshine and the Earth’s albedo: 1. Earthshine observations and measurements of the lunar phase function for accurate measurements of the Earth’s bond albedo. J Geophys Res (Atmos) 108:4709Google Scholar
  66. Reinhard CT, Olson SL, Schwieterman EW, Lyons TW (2017) False negatives for remote life detection on ocean-bearing planets: lessons from the early Earth. Astrobiology 17:287–297ADSCrossRefGoogle Scholar
  67. Robinson TD, Meadows VS, Crisp D et al (2011) Earth as an extrasolar planet: Earth model validation using EPOXI Earth observations. Astrobiology 11:393–408Google Scholar
  68. Rosing MT, Bird DK, Sleep NH, Bjerrum CJ (2010) No climate paradox under the faint early Sun. Nature 464:744–747Google Scholar
  69. Rossow WB, Walker AW, Beuschel DE, Roiter MD (1996) International satellite cloud climatology project (ISCCP): documentation of new cloud datasets. World climate research programme report WMO/TD 737, World meteorological organization, GenevaGoogle Scholar
  70. Rushby AJ, Claire MW, Osborn H, Watson AJ (2013) Habitable zone lifetimes of exoplanets around main sequence stars. Astrobiology 13:833–849ADSCrossRefGoogle Scholar
  71. Sanromá E Pallé E (2012) Reconstructing the photometric light curves of Earth as a planet along its history. ApJ 744:188Google Scholar
  72. Sanromá E, Pallé E, García Munõz A (2013) On the effects of the evolution of microbial mats and land plants on the Earth as a planet. photometric and spectroscopic light curves of Paleo-Earths. ApJ 766:133ADSCrossRefGoogle Scholar
  73. Scheer H (2003) The pigments. In: Green BR, Parson WW (eds) Advances in photosynthesis and respiration. Light-harvesting antennas in photosynthesis, vol 13. Kluwer Academic, Dordrecht, pp 29–81CrossRefGoogle Scholar
  74. Schneider J, Léger A, Fridlund M et al (2010) The far future of exoplanet direct characterization. Astrobiology 10:121–126ADSCrossRefGoogle Scholar
  75. Schulze-Makuch D, Guinan E (2016) Another Earth 2.0? not so fast. Astrobiology 16:817–821Google Scholar
  76. Seager S, Turner EL, Schafer J, Ford EB (2005) Vegetation’s red edge: a possible spectroscopic biosignature of extraterrestrial plants. Astrobiology 5:372–390Google Scholar
  77. Seckbach J, Oren A (2010) Microbial mats: modern and ancient microorganisms in stratified systems. Cellular origin, life in extreme habitats and astrobiology. Springer, LondonGoogle Scholar
  78. Sterzik MF, Bagnulo S, Pallé E (2012) Biosignatures as revealed by spectropolarimetry of Earthshine. Nature 483:64–66ADSCrossRefGoogle Scholar
  79. Stüeken EE (2016) Nitrogen in ancient mud: a biosignature? Astrobiology 16:730–735ADSCrossRefGoogle Scholar
  80. Stüeken EE, Kipp MA, Koehler MC et al (2016) Modeling pN2 through geological time: implications for planetary climates and atmospheric biosignatures. Astrobiology 16:949–963Google Scholar
  81. Tarduno JA, Cottrell RD, Watkeys MK et al (2010) Geodynamo, solar wind, and magnetopause 3.4 to 3.45 billion years ago. Science 327:1238Google Scholar
  82. Tarduno JA, Cottrell RD, Davis WJ, Nimmo F, Bono RK (2015) A Hadean to Paleoarchean geodynamo recorded by single zircon crystals. Science 349:521–524Google Scholar
  83. Tian F, Toon OB, Pavlov AA, De Sterck H (2005) A Hydrogen-rich early Earth atmosphere. Science 308:1014–1017Google Scholar
  84. Tinetti G, Meadows VS, Crisp D et al (2006a) Detectability of planetary characteristics in disk-averaged spectra. I: the Earth model. Astrobiology 6:34–47ADSCrossRefGoogle Scholar
  85. Tinetti G, Meadows VS, Crisp D et al (2006b) Detectability of planetary characteristics in disk-averaged spectra II: synthetic spectra and light-curves of Earth. Astrobiology 6:881–900ADSCrossRefGoogle Scholar
  86. Tinetti G, Rashby S, Yung YL (2006c) Detectability of red-edge-shifted vegetation on terrestrial planets orbiting M Stars. ApJ 644:L129–L132ADSCrossRefGoogle Scholar
  87. Turnbull MC, Traub WA, Jucks KW et al (2006) Spectrum of a habitable world: earthshine in the near-infrared. ApJ 644:551–559ADSCrossRefGoogle Scholar
  88. Udry S, Bonfils X, Delfosse X et al (2007) The HARPS search for southern extra-solar planets. XI. super-earths (5 and 8 M{øplus}) in a 3-planet system. A&A 469:L43–L47Google Scholar
  89. Vázquez M, Pallé E Montañés Rodríguez P (2010a) The earth as a distant planet. https://doi.org/10.1007/978-1-4419-1684-6
  90. Vázquez M, Pallé E, Rodríguez PM (2010b) The Earth as a distant planet. https://doi.org/10.1007/978-1-4419-1684-6
  91. Walker JCG (1977) Evolution of the atmosphere. Macmillan/Collier Macmillan, New York/London. http://adsabs.harvard.edu/abs/1977evat.book.....W
  92. Wilde SA, Valley JW, Peck WH, Graham CM (2001) Evidence from detrital zircons for the existence of continental crust and oceans on the Earth 4.4 Gyr ago. Nature 409:175–178ADSCrossRefGoogle Scholar
  93. Woolf NJ, Smith PS, Traub WA, Jucks KW (2002) The spectrum of earthshine: a pale blue dot observed from the ground. ApJ 574:430–433ADSCrossRefGoogle Scholar
  94. Wright JT, Sigurdsson S (2016) Families of plausible solutions to the puzzle of Boyajian Star. ApJ 829:L3ADSCrossRefGoogle Scholar
  95. Xiong J, Fischer W, Inoue K, Nakahara M, Bauer C (2000) Molecular evidence for the early evolution of photosynthesis. Science 289(5485):1724–1730ADSCrossRefGoogle Scholar

Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Instituto de Astrofísica de CanariasLa LagunaSpain

Section editors and affiliations

  • Victoria Meadows
    • 1
  • Rory Barnes
    • 2
  1. 1.Astronomy DepartmentUniversity of WashingtonSeattleUSA
  2. 2.Astronomy DepartmentUniversity of WashingtonSeattleUSA

Personalised recommendations