A search for life on Earth from the Galileo spacecraft
Abstract
In its December 1990 fly-by of Earth, the Galileo spacecraft found evidence of abundant gaseous oxygen, a widely distributed surface pigment with a sharp absorption edge in the red part of the visible spectrum, and atmospheric methane in extreme thermodynamic disequilibrium; together, these are strongly suggestive of life on Earth. Moreover, the presence of narrow-band, pulsed, amplitude-modulated radio transmission seems uniquely attributable to intelligence. These observations constitute a control experiment for the serach for extraterrestrial life by modern interplanetary spacecraft.
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The detection of both O2 and CH4, a classic disequilibrium biosignature, would have been lost to observers.
“Moreover, the detection of both, a classic disequilibrium biosignature (e.g., Sagan et al., 1993), would have been lost to observers.”
From Oxygenation, Life, and the Planetary System during Earth's Middle History: An Overview (2021) · cites this paper as Sagan et al., 1993
The Galileo spacecraft demonstrated that atmospheric disequilibrium could be remotely detected via spectroscopy of Earth's atmosphere.
“The Galileo spacecraft, when doing a flyby of Earth, demonstrated that this disequilibrium could be remotely detected via spectroscopy of the atmosphere of the planet; this is similar to plans to detect this disequilibrium on potentially habitable extrasolar planets (Sagan et al., 1993; see also Section 7.2.2).”
From The Astrobiology Primer v2.0 (2016) · cites this paper as Sagan et al., 1993
Atmospheric species such as oxygen and methane (and other reduced gases) should not coexist in appreciable quantities in an equilibrium atmosphere, yet they do on Earth.
“Atmospheric species such as oxygen and methane (and other reduced gases) should not coexist in appreciable quantities in an equilibrium atmosphere (Lovelock, 1965; Sagan et al., 1993), yet they do on our living planet.”
From The Astrobiology Primer v2.0 (2016) · cites this paper as Sagan et al., 1993
Atmospheric chemical disequilibrium is a more general biosignature, evident in the coexistence of two or more long-term incompatible gases.
“A more general biosignature, which has not been considered for the early Earth, is atmospheric chemical disequilibrium, evident in the coexistence of two or more long-term incompatible gases (17–20).”
From Disequilibrium biosignatures over Earth history and implications for detecting exoplanet life (2018) · cites this paper as [20]
Cites
Gold, T. (1992) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.89.13.6045 · Cited by 655 · see citing works
The Earth as a radio source: Terrestrial kilometric radiation
Gurnett, D. A. (1974) · Journal of Geophysical Research Atmospheres · doi:10.1029/ja079i028p04227 · Cited by 589 · see citing works
Self-citationA Physical Basis for Life Detection Experiments
LOVELOCK, J. E. (1965) · Nature · doi:10.1038/207568a0 · Cited by 446 · see citing works
Intelligent life in the Universe
ÖPIK, E. J. (1967) · Planetary and Space Science · doi:10.1016/0032-0633(67)90095-5 · Cited by 333 · see citing works
Chapman, S. (1931) · Proceedings of the Physical Society · doi:10.1088/0959-5309/43/5/302 · Cited by 321 · see citing works
Intelligent Life in the Universe
Ulmschneider, P. (2006) · Advances in astrobiology and biogeophysics · doi:10.1007/3-540-32838-6 · Cited by 274 · see citing works
Near-Infrared Mapping Spectrometer experiment on Galileo
Carlson, R. W., WEISSMAN, P. R., Smythe, W. D., Mahoney, J. C., & Teams, T. N. S. A. E. (1992) · Space Science Reviews · doi:10.1007/bf00216865 · Cited by 223 · see citing works
Self-citationThe Galileo Solid-State Imaging experiment
Belton, M. J. S., Klaasen, K. P., Clary, M. C., Anderson, J. L., Anger, C. D., Carr, M. H., Chapman, C. R., Davies, M. E., Greeley, R., Anderson, D. L., et al. (1992) · Space Science Reviews · doi:10.1007/bf00216864 · Cited by 138 · see citing works
Satellite observations of type III solar radio bursts at low frequencies
Fainberg, J., & Stone, R. (1974) · Space Science Reviews · doi:10.1007/bf00240885 · Cited by 125 · see citing works
Signs of Life: Criterion-System of Exobiology
Lederberg, J. (1965) · Nature · doi:10.1038/207009a0 · Cited by 123 · see citing works
The Galileo Plasma wave investigation
Gurnett, D. A., Kurth, W. S., Shaw, R. R., Roux, A., Gendrin, R., Kennel, C. F., Scarf, F. L., & Shawhan, S. D. (1992) · Space Science Reviews · doi:10.1007/bf00216861 · Cited by 120 · see citing works
Self-citationMethane on the greenhouse agenda
Hogan, K. B., Hoffman, J. S., & Thompson, A. M. (1991) · Nature · doi:10.1038/354181a0 · Cited by 117 · see citing works
Owen, T. (1980) · Astrophysics and space science library · doi:10.1007/978-94-009-9115-6_17 · Cited by 112 · see citing works
The Galileo Plasma Wave Investigation
Gurnett, D. A., Kurth, W. S., Shaw, R. R., Roux, A., Gendrin, R., Kennel, C. F., Scarf, F. L., & Shawhan, S. D. (1992) · Springer eBooks · doi:10.1007/978-94-011-2512-3_14 · Cited by 112 · see citing works
Self-citationMitchell, A., & Henderson, L. J. (1913) · The Journal of Philosophy Psychology and Scientific Methods · doi:10.2307/2013288 · Cited by 107 · see citing works
Strategies for the Search for Life in the Universe
Papagiannis, M. D. (1980) · Astrophysics and space science library · doi:10.1007/978-94-009-9115-6 · Cited by 100 · see citing works
Stevenson, D. J. (1984) · Icarus · doi:10.1016/0019-1035(84)90178-7 · Cited by 79 · see citing works
Eavesdropping: The Radio Signature of the Earth
Sullivan, W. T., Brown, S., & Wetherill, C. (1978) · Science · doi:10.1126/science.199.4327.377 · Cited by 79 · see citing works
Thermodynamic Equilibria in Planetary Atmospheres
Lippincott, E. R., Eck, R. V., Dayhoff, M. O., & Sagan, C. (1967) · The Astrophysical Journal · doi:10.1086/149051 · Cited by 73 · see citing works
Self-citationBiology and the Exploration of Mars
Roland, C. G. (1966) · JAMA · doi:10.1001/jama.1966.03110090100047 · Cited by 60 · see citing works
Galileo Ultraviolet Spectrometer experiment
Hord, C. W., McClintock, W. E., Stewart, A. I. F., Barth, C. A., Esposito, L. W., Thomas, G. E., Sandel, B. R., Hunten, D. M., Broadfoot, A. L., Shemansky, D. E., et al. (1992) · Space Science Reviews · doi:10.1007/bf00216866 · Cited by 53 · see citing works
Self-citationBiology and the Exploration of Mars
National Research Council (1966) · National Academies Press eBooks · doi:10.17226/12409 · Cited by 50 · see citing works
MICROENVIRONMENTS FOR LIFE ON MARS
Lederberg, J., & Sagan, C. (1962) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.48.9.1473 · Cited by 46 · see citing works
Self-citationPhysics of the Earth's Upper Atmosphere
Dwight, C. H. (1966) · American Journal of Physics · doi:10.1119/1.1973181 · Cited by 32 · see citing works
A search for life on Earth at kilometer resolution
Kilston, S. D., Drummond, R. R., & Sagan, C. (1966) · Icarus · doi:10.1016/0019-1035(66)90010-8 · Cited by 18 · see citing works
Self-citationNatural and man‐made emissions at 1.0–5.6 MHz measured between 10 and 18 RE
LaBelle, J. W., Treumann, R. A., Boehm, M. H., & Gewecke, K. (1989) · Radio Science · doi:10.1029/rs024i006p00725 · Cited by 17 · see citing works
A search for life on Earth at 100 meter resolution
Sagan, C., & Wallace, D. K. (1971) · Icarus · doi:10.1016/0019-1035(71)90132-1 · Cited by 8 · see citing works
Self-citation
Flagged first, then by citations
1 of the 28 references couldn’t be matched to a known paper.
Cited by
Sorted by citations
Biogeochemical Controls and Feedbacks on Ocean Primary Production
Falkowski, P. G., Barber, R. T., & Smetacek, V. (1998) · Science · doi:10.1126/science.281.5374.200 · Cited by 2,848 · see citing works
Anaerobic Metabolism: Linkages to Trace Gases and Aerobic Processes
Megonigal, J. P., Hines, M. E., & Visscher, P. T. (2003) · Elsevier eBooks · doi:10.1016/b0-08-043751-6/08132-9 · Cited by 577 · see citing works
Remote Sensing of Planetary Properties and Biosignatures on Extrasolar Terrestrial Planets
Marais, D. J. D., Harwit, M. O., Jucks, K. W., Kasting, J. F., Lin, D. N. C., Lunine, J. I., Schneider, J. L., Seager, S., Traub, W. A., & WOOLF, N. J. (2002) · Astrobiology · doi:10.1089/15311070260192246 · Cited by 526 · see citing works
Exoplanet Biosignatures: A Review of Remotely Detectable Signs of Life
Schwieterman, E. W., Kiang, N. Y., Parenteau, M. N., Harman, C. E., DasSarma, S., Fisher, T. M., Arney, G. N., Hartnett, H. E., Reinhard, C. T., Olson, S. L., et al. (2018) · Astrobiology · doi:10.1089/ast.2017.1729 · Cited by 581 · see citing works
Exoplanet Biosignatures: A Review of Remotely Detectable Signs of Life
Schwieterman, E. W., Kiang, N. Y.-L., Parenteau, M. N., Harman, C. E., DasSarma, S., Fisher, T. M., Arney, G., Hartnett, H. E., Reinhard, C. T., Olson, S. L., et al. (2017) · eScholarship (California Digital Library) · Cited by 452 · see citing works
ExoMol line lists – IV. The rotation–vibration spectrum of methane up to 1500 K
Yurchenko, S. N., & Tennyson, J. (2014) · Monthly Notices of the Royal Astronomical Society · doi:10.1093/mnras/stu326 · Cited by 428 · see citing works
Perryman, M. A. C. (2011) · Cambridge University Press eBooks · doi:10.1017/9781108304160 · Cited by 343 · see citing works
Ozone Concentrations and Ultraviolet Fluxes on Earth-Like Planets Around Other Stars
Segura, A., Krelove, K., Kasting, J. F., Sommerlatt, D., Meadows, V., Crisp, D., Cohen, M., & Mlawer, E. (2003) · Astrobiology · doi:10.1089/153110703322736024 · Cited by 379 · see citing works
The Pale Orange Dot: The Spectrum and Habitability of Hazy Archean Earth
Arney, G., Domagal-Goldman, S. D., Meadows, V. S., Wolf, E. T., Schwieterman, E., Charnay, B., Claire, M., Hébrard, E., & Trainer, M. G. (2016) · Astrobiology · doi:10.1089/ast.2015.1422 · Cited by 327 · see citing works
“Additionally, although we anticipate planetary diversity in the exoplanet population, existing spectral studies are largely focused on the observables of modern-day Earth ( e.g. , Sagan et al. , 1993; Woolf et al. , 2002; Robinson et al. , 2011, 2014a).”
Spectral Signatures of Photosynthesis. I. Review of Earth Organisms
Kiang, N. Y., Siefert, J., Govindjee, & Blankenship, R. E. (2007) · Astrobiology · doi:10.1089/ast.2006.0105 · Cited by 327 · see citing works
Vegetation's Red Edge: A Possible Spectroscopic Biosignature of Extraterrestrial Plants
Seager, S., Turner, E. L., Schafer, J., & Ford, E. B. (2005) · Astrobiology · doi:10.1089/ast.2005.5.372 · Cited by 340 · see citing works
Neveu, M. F., Hays, L. E., Voytek, M. A., New, M. H., & Schulte, M. D. (2018) · Astrobiology · doi:10.1089/ast.2017.1773 · Cited by 277 · see citing works
How to Characterize Habitable Worlds and Signs of Life
Kaltenegger, L. (2017) · Annual Review of Astronomy and Astrophysics · doi:10.1146/annurev-astro-082214-122238 · Cited by 245 · see citing works
Spectral signatures of photosynthesis I: Review of Earth organisms
Kiang, N. Y., Siefert, J., & Blankenship, R. E. (2007) · CERN Document Server (European Organization for Nuclear Research) · Cited by 238 · see citing works
ALIEN MAPS OF AN OCEAN-BEARING WORLD
Cowan, N. B., Agol, E., Meadows, V., Robinson, T. D., Livengood, T. A., Deming, D., Lisse, C. M., A’Hearn, M. F., Wellnitz, D. D., Seager, S., et al. (2009) · The Astrophysical Journal · doi:10.1088/0004-637x/700/2/915 · Cited by 226 · see citing works
Exoplanet Biosignatures: A Framework for Their Assessment
Catling, D. C., Krissansen-Totton, J., Kiang, N. Y., Crisp, D., Robinson, T. D., DasSarma, S., Rushby, A. J., Del Genio, A., Bains, W., & Domagal-Goldman, S. (2018) · Astrobiology · doi:10.1089/ast.2017.1737 · Cited by 225 · see citing works
Characterization of extrasolar terrestrial planets from diurnal photometric variability
Ford, E. B., Seager, S., & Turner, E. L. (2001) · Nature · doi:10.1038/35091009 · Cited by 212 · see citing works
Oxygenation, Life, and the Planetary System during Earth's Middle History: An Overview
Lyons, T. W., Diamond, C. W., Planavsky, N. J., Reinhard, C. T., & Li, C. (2021) · Astrobiology · doi:10.1089/ast.2020.2418 · Cited by 211 · see citing works
“Moreover, the detection of both, a classic disequilibrium biosignature (e.g., Sagan et al., 1993), would have been lost to observers.”
BackgroundJacquemoud, S., & Ustin, S. L. (2019) · Cambridge University Press eBooks · doi:10.1017/9781108686457 · Cited by 210 · see citing works
Dartnell, L. R. (2011) · Astrobiology · doi:10.1089/ast.2010.0528 · Cited by 206 · see citing works
Earth as an Extrasolar Planet: Earth Model Validation Using EPOXI Earth Observations
Robinson, T. D., Meadows, V., Crisp, D., Deming, D., A’Hearn, M. F., Charbonneau, D., Livengood, T. A., Seager, S., Barry, R. K., Hearty, T., et al. (2011) · Astrobiology · doi:10.1089/ast.2011.0642 · Cited by 204 · see citing works
The physical properties of extra-solar planets
Baraffe, I., Chabrier, G., & Barman, T. (2009) · Reports on Progress in Physics · doi:10.1088/0034-4885/73/1/016901 · Cited by 193 · see citing works
Detection of Ozone on Ganymede
Noll, K., Johnson, R. E., Lane, A. L., Domingue, D. L., & Weaver, H. A. (1996) · Science · doi:10.1126/science.273.5273.341 · Cited by 187 · see citing works
FEASIBILITY STUDIES FOR THE DETECTION OF O2IN AN EARTH-LIKE EXOPLANET
Rodler, F., & López‐Morales, M. (2014) · The Astrophysical Journal · doi:10.1088/0004-637x/781/1/54 · Cited by 184 · see citing works
EFFECT OF UV RADIATION ON THE SPECTRAL FINGERPRINTS OF EARTH-LIKE PLANETS ORBITING M STARS
Rugheimer, S., Kaltenegger, L., Segura, A., Linsky, J. L., & Mohanty, S. (2015) · The Astrophysical Journal · doi:10.1088/0004-637x/809/1/57 · Cited by 181 · see citing works
Spectral comparison of heavily hydrated salts with disrupted terrains on Europa
Dalton, J. B., Prieto‐Ballesteros, O., Kargel, J. S., Jamieson, C. S., Jolivet, J., & Quinn, R. C. (2005) · Icarus · doi:10.1016/j.icarus.2005.02.023 · Cited by 179 · see citing works
Signature of life on exoplanets: Can Darwin produce false positive detections?
Selsis, F., Despois, D., & Parisot, J. P. (2002) · Astronomy and Astrophysics · doi:10.1051/0004-6361:20020527 · Cited by 175 · see citing works
Earth’s transmission spectrum from lunar eclipse observations
Πάλλη, Ε., Osorio, M. R. Z., Barrena, R., Montañés-Rodríguez, P., & Martín, E. L. (2009) · Nature · doi:10.1038/nature08050 · Cited by 177 · see citing works
Arnold, L., Gillet, S., Lardière, O., Riaud, P., & Schneider, J. (2002) · arXiv (Cornell University) · doi:10.1051/0004-6361:20020933 · Cited by 9 · see citing works
Disequilibrium biosignatures over Earth history and implications for detecting exoplanet life
Krissansen-Totton, J., Olson, S., & Catling, D. C. (2018) · Science Advances · doi:10.1126/sciadv.aao5747 · Cited by 177 · see citing works
Reflections on O <sub>2</sub> as a Biosignature in Exoplanetary Atmospheres
Meadows, V. S. (2017) · Astrobiology · doi:10.1089/ast.2016.1578 · Cited by 173 · see citing works
Spectropolarimetric signatures of Earth-like extrasolar planets
Stam, D. M. (2008) · Astronomy and Astrophysics · doi:10.1051/0004-6361:20078358 · Cited by 166 · see citing works
Habitability and Biosignatures of Hycean Worlds
Madhusudhan, N., Piette, A. A. A., & Constantinou, S. (2021) · The Astrophysical Journal · doi:10.3847/1538-4357/abfd9c · Cited by 170 · see citing works
Biosignatures as revealed by spectropolarimetry of Earthshine
Sterzik, M., Bagnulo, S., & Πάλλη, Ε. (2012) · Nature · doi:10.1038/nature10778 · Cited by 164 · see citing works
Hu, R., Seager, S., & Bains, W. (2013) · The Astrophysical Journal · doi:10.1088/0004-637x/769/1/6 · Cited by 150 · see citing works
Spectroscopy of planetary atmospheres in our Galaxy
Tinetti, G., Encrenaz, T., & Coustenis, A. (2013) · The Astronomy and Astrophysics Review · doi:10.1007/s00159-013-0063-6
Using Biogenic Sulfur Gases as Remotely Detectable Biosignatures on Anoxic Planets
Domagal-Goldman, S. D., Meadows, V. S., Claire, M. W., & Kasting, J. F. (2011) · Astrobiology · doi:10.1089/ast.2010.0509 · Cited by 191 · see citing works
The dual origin of the terrestrial atmosphere
Dauphas, N. (2003) · Icarus · doi:10.1016/s0019-1035(03)00198-2 · Cited by 115 · see citing works
DETECTING OCEANS ON EXTRASOLAR PLANETS USING THE GLINT EFFECT
Robinson, T. D., Meadows, V. S., & Crisp, D. (2010) · The Astrophysical Journal Letters · doi:10.1088/2041-8205/721/1/l67 · Cited by 152 · see citing works
Spectral Fingerprints of Earth-like Planets Around FGK Stars
Rugheimer, S., Kaltenegger, L., Zsom, A., Segura, A., & Sasselov, D. (2013) · Astrobiology · doi:10.1089/ast.2012.0888 · Cited by 143 · see citing works
Feng, Y. K., Robinson, T. D., Fortney, J. J., Lupu, R. E., Marley, M. S., Lewis, N. K., Macintosh, B., & Line, M. R. (2018) · The Astronomical Journal · doi:10.3847/1538-3881/aab95c · Cited by 138 · see citing works
The transmission spectrum of Earth-size transiting planets
Ehrenreich, D., Tinetti, G., Etangs, A. L. D., Vidal‐Madjar, A., & Selsis, F. (2006) · Astronomy and Astrophysics · doi:10.1051/0004-6361:20053861 · Cited by 133 · see citing works
Domagal-Goldman, S. D., Wright, K. E., Domagal-Goldman, S. D., Wright, K. E., Adamala, K., Arina de la Rubia, L., Bond, J., Dartnell, L. R., Goldman, A. D., Lynch, K., et al. (2016) · Astrobiology · doi:10.1089/ast.2015.1460 · Cited by 136 · see citing works
“…when doing a flyby of Earth, demonstrated that this disequilibrium could be remotely detected via spectroscopy of the atmosphere of the planet; this is similar to plans to detect this disequilibrium on potentially habitable extrasolar planets (Sagan et al., 1993; see also Section 7.2.2).”
InfluentialDeciphering Biosignatures in Planetary Contexts
Chan, M. A., Hinman, N. W., Potter‐McIntyre, S. L., Schubert, K. E., Gillams, R. J., Awramik, S. M., Boston, P. J., Bower, D. M., Marais, D. J. D., Farmer, J. D., et al. (2019) · Astrobiology · doi:10.1089/ast.2018.1903 · Cited by 127 · see citing works
Pilcher, C. B. (2003) · Astrobiology · doi:10.1089/153110703322610582 · Cited by 126 · see citing works
Exoplanet Biosignatures: Future Directions
Walker, S. I., Bains, W., Cronin, L., DasSarma, S., Danielache, S. O., Domagal-Goldman, S. D., Kaçar, B., Kiang, N. Y.-L., Lenardic, A., Reinhard, C. T., et al. (2018) · Astrobiology · doi:10.1089/ast.2017.1738 · Cited by 122 · see citing works
Tides and the Evolution of Planetary Habitability
Barnes, R., Raymond, S. N., Jackson, B., & Greenberg, R. (2008) · Astrobiology · doi:10.1089/ast.2007.0204 · Cited by 122 · see citing works
On Detecting Biospheres from Chemical Thermodynamic Disequilibrium in Planetary Atmospheres
Krissansen-Totton, J., Bergsman, D. S., & Catling, D. C. (2016) · Astrobiology · doi:10.1089/ast.2015.1327 · Cited by 132 · see citing works
Spectrum of hot methane in astronomical objects using a comprehensive computed line list
Yurchenko, S. N., Tennyson, J., Bailey, J., Hollis, M. D. J., & Tinetti, G. (2014) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1324219111 · Cited by 119 · see citing works
Synthetic Spectra of Simulated Terrestrial Atmospheres Containing Possible Biomarker Gases
Schindler, T. (2000) · Icarus · doi:10.1006/icar.2000.6340 · Cited by 117 · see citing works
The Pale Orange Dot: The Spectrum and Habitability of Hazy Archean Earth
Arney, G., Domagal-Goldman, S. D., Meadows, V., Wolf, E. T., Schwieterman, E. W., Charnay, B., Claire, M. W., Hébrard, É., & Trainer, M. G. (2025) · Figshare · Cited by 117 · see citing works
DETECTION OF OCEAN GLINT AND OZONE ABSORPTION USINGLCROSSEARTH OBSERVATIONS
Robinson, T. D., Ennico, K., Meadows, V., Sparks, W. B., Bussey, D. B. J., Schwieterman, E. W., & Breiner, J. (2014) · The Astrophysical Journal · doi:10.1088/0004-637x/787/2/171 · Cited by 115 · see citing works
Gaia as a complex adaptive system
Lenton, T. M., & Oijen, M. A. V. (2002) · Philosophical Transactions of the Royal Society B Biological Sciences · doi:10.1098/rstb.2001.1014 · Cited by 115 · see citing works
Astrobiology: Exploring the Origins, Evolution, and Distribution of Life in the Universe
Marais, D. J. D., & Walter, M. R. (1999) · Annual Review of Ecology and Systematics · doi:10.1146/annurev.ecolsys.30.1.397 · Cited by 113 · see citing works
<i>Darwin</i> —A Mission to Detect and Search for Life on Extrasolar Planets
Cockell, C. S., Léger, A., Fridlund, M., Herbst, T. M., Kaltenegger, L., Absil, O., Beichman, C., Benz, W., Blanc, M., Brack, A., et al. (2009) · Astrobiology · doi:10.1089/ast.2007.0227 · Cited by 115 · see citing works
Montañés-Rodríguez, P., Πάλλη, Ε., Goode, P. R., & Martín‐Torres, J. (2006) · The Astrophysical Journal · doi:10.1086/507694 · Cited by 105 · see citing works
Habitability and Biosignatures of Hycean Worlds
Madhusudhan, N., Piette, A. A. A., & Constantinou, S. (2021) · Apollo (University of Cambridge) · doi:10.17863/cam.76040 · Cited by 104 · see citing works
Abiotic Production of Methane in Terrestrial Planets
Guzmán-Marmolejo, A., Segura, A., & Escobar-Briones, E. (2013) · Astrobiology · doi:10.1089/ast.2012.0817 · Cited by 96 · see citing works
False Negatives for Remote Life Detection on Ocean-Bearing Planets: Lessons from the Early Earth
Reinhard, C. T., Olson, S. L., Schwieterman, E. W., & Lyons, T. W. (2017) · Astrobiology · doi:10.1089/ast.2016.1598 · Cited by 93 · see citing works
Optical Sensing and Imaging of Trace Oxygen with Record Response
Nagl, S., Baleizão, C., Borisov, S. M., Schäferling, M., Berberan-Santos, M. N., & Wolfbeis, O. S. (2007) · Angewandte Chemie International Edition · doi:10.1002/anie.200603754 · Cited by 92 · see citing works
ExoMol molecular line lists – XXVII. Spectra of C2H4
Mant, B. P., Yachmenev, A., Tennyson, J., & Yurchenko, S. N. (2018) · Monthly Notices of the Royal Astronomical Society · doi:10.1093/mnras/sty1239 · Cited by 91 · see citing works
Ecosystem functioning and intrinsic value of biodiversity
Ghilarov, A. M. (2000) · Oikos · doi:10.1034/j.1600-0706.2000.900222.x · Cited by 105 · see citing works
DETECTING AND CONSTRAINING N<sub>2</sub>ABUNDANCES IN PLANETARY ATMOSPHERES USING COLLISIONAL PAIRS
Schwieterman, E. W., Robinson, T. D., Meadows, V. S., Misra, A., & Domagal-Goldman, S. (2015) · The Astrophysical Journal · doi:10.1088/0004-637x/810/1/57 · Cited by 100 · see citing works
Deciphering Spectral Fingerprints of Habitable Exoplanets
Kaltenegger, L., Selsis, F., Fridlund, M., Lammer, H., Beichman, C., Danchi, W., Eiroa, C., Henning, T., Herbst, T., Léger, A., et al. (2009) · Astrobiology · doi:10.1089/ast.2009.0381 · Cited by 86 · see citing works
Properties of an Earth-Like Planet Orbiting a Sun-Like Star: Earth Observed by the EPOXI Mission
Livengood, T. A., Deming, D., A’Hearn, M. F., Charbonneau, D., Hewagama, T., Lisse, C. M., McFadden, L. A., Meadows, V., Robinson, T. D., Seager, S., et al. (2011) · Astrobiology · doi:10.1089/ast.2011.0614 · Cited by 87 · see citing works
On the Habitability and Future Exploration of Ocean Worlds
Hand, K. P., Sotin, C., Hayes, A. G., & Coustenis, A. (2020) · Space Science Reviews · doi:10.1007/s11214-020-00713-7 · Cited by 86 · see citing works
Perryman, M. A. C. (2018) · Cambridge University Press eBooks · doi:10.1017/9781108304160.017 · Cited by 89 · see citing works
Nonphotosynthetic Pigments as Potential Biosignatures
Schwieterman, E. W., Cockell, C. S., & Meadows, V. (2015) · Astrobiology · doi:10.1089/ast.2014.1178 · Cited by 82 · see citing works
Non-equilibrium thermodynamics of light absorption
Meszéna, G., & Westerhoff, H. V. (1999) · Journal of Physics A Mathematical and General · doi:10.1088/0305-4470/32/2/006 · Cited by 81 · see citing works
A Review of Exoplanetary Biosignatures
Grenfell, J. (2017) · Physics Reports · doi:10.1016/j.physrep.2017.08.003 · Cited by 55 · see citing works
Spectra of Earth-like Planets through Geological Evolution around FGKM Stars
Rugheimer, S., & Kaltenegger, L. (2018) · The Astrophysical Journal · doi:10.3847/1538-4357/aaa47a · Cited by 76 · see citing works
Detecting Ocean Glint on Exoplanets Using Multiphase Mapping
Lustig‐Yaeger, J., Meadows, V., Mendoza, G. T., Schwieterman, E. W., Fujii, Y., Luger, R., & Robinson, T. D. (2018) · The Astronomical Journal · doi:10.3847/1538-3881/aaed3a · Cited by 73 · see citing works
HABITABLE ZONES AROUND LOW MASS STARS AND THE SEARCH FOR EXTRATERRESTRIAL LIFE
Kasting, J. F. (1997) · Origins of Life and Evolution of Biospheres · doi:10.1023/a:1006586517202 · Cited by 73 · see citing works
State-of-the-art instruments for detecting extraterrestrial life
Bada, J. L. (2001) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.98.3.797 · Cited by 71 · see citing works
Exoplanet Biosignatures: At the Dawn of a New Era of Planetary Observations
Kiang, N. Y.-L., Domagal-Goldman, S. D., Parenteau, M. N., Catling, D. C., Fujii, Y., Meadows, V., Schwieterman, E. W., & Walker, S. I. (2018) · Astrobiology · doi:10.1089/ast.2018.1862 · Cited by 68 · see citing works
Spectral Behavior of Hydrated Sulfate Salts: Implications for Europa Mission Spectrometer Design
Dalton, J. B. (2003) · Astrobiology · doi:10.1089/153110703322736097 · Cited by 71 · see citing works
The Earth as an extrasolar transiting planet
Vidal‐Madjar, A., Arnold, L., Ehrenreich, D., Ferlet, R., Etangs, A. L. D., Bouchy, F., Ségransan, D., Boisse, I., Hébrard, G., Moutou, C., et al. (2010) · Astronomy and Astrophysics · doi:10.1051/0004-6361/201014751 · Cited by 71 · see citing works
Barge, L. M., Branscomb, E., Brucato, J. R., Cardoso, S. S. S., Cartwright, J. H. E., Danielache, S. O., Galante, D., Kee, T. P., Miguel, Y., Mojzsis, S. J., et al. (2016) · Origins of Life and Evolution of Biospheres · doi:10.1007/s11084-016-9508-z · Cited by 70 · see citing works
Lammer, H., Sproß, L., Grenfell, J. L., Scherf, M., Fossati, L., Lendl, M., & Cubillos, P. E. (2019) · Astrobiology · doi:10.1089/ast.2018.1914 · Cited by 67 · see citing works
Chen, H., Wolf, E. T., Zhan, Z., & Horton, D. E. (2019) · The Astrophysical Journal · doi:10.3847/1538-4357/ab4f7e · Cited by 65 · see citing works
Anaerobic Metabolism: Linkages to Trace Gases and Aerobic Processes
Megonigal, J. P., Hines, M. E., & Visscher, P. T. (2013) · Elsevier eBooks · doi:10.1016/b978-0-08-095975-7.00808-1 · Cited by 78 · see citing works
Astrobiology: Future Perspectives
Ehrenfreund, P., Irvine, W. M., Owen, T., Becker, L., Blank, J. G., Brucato, J. R., Colangeli, L., Derenne, S., Dutrey, A., Despois, D., et al. (2005) · Springer eBooks · doi:10.1007/1-4020-2305-7 · Cited by 69 · see citing works
Xu, J., Ramian, G. J., Galan, J. F., Savvidis, P. G., Scopatz, A., Birge, R. R., Allen, S. J., & Plaxco, K. W. (2003) · Astrobiology · doi:10.1089/153110703322610609 · Cited by 67 · see citing works
ASTRONOMICAL SEARCHES FOR EARTH-LIKE PLANETS AND SIGNS OF LIFE
WOOLF, N. J., & Angel, J. R. P. (1998) · Annual Review of Astronomy and Astrophysics · doi:10.1146/annurev.astro.36.1.507 · Cited by 67 · see citing works
Detecting Oceans on Extrasolar Planets Using the Glint EffectPreprint
Crisp, D. (2016) · Cited by 67 · see citing works
Habitable Zones Around Low Mass Stars and the Search for Extraterrestrial Life
Kasting, J. F. (1997) · Springer eBooks · doi:10.1007/978-94-015-8907-9_15 · Cited by 65 · see citing works
ROTATIONAL VARIABILITY OF EARTH'S POLAR REGIONS: IMPLICATIONS FOR DETECTING SNOWBALL PLANETS
Cowan, N. B., Robinson, T. D., Livengood, T. A., Deming, D., Agol, E., A’Hearn, M. F., Charbonneau, D., Lisse, C. M., Meadows, V., Seager, S., et al. (2011) · The Astrophysical Journal · doi:10.1088/0004-637x/731/1/76 · Cited by 64 · see citing works
Lineweaver, C., & Chopra, A. (2012) · Annual Review of Earth and Planetary Sciences · doi:10.1146/annurev-earth-042711-105531 · Cited by 61 · see citing works
On the protection of extrasolar Earth-like planets around K/M stars against galactic cosmic rays
Grießmeier, J. ‐., Stadelmann, A., Grenfell, J. L., Lammer, H., & Motschmann, U. (2008) · Icarus · doi:10.1016/j.icarus.2008.09.015 · Cited by 63 · see citing works
From NO to OO: Nitric Oxide and Dioxygen in Bacterial Respiration
Hendriks, J. H. M., Gohlke, U., & Saraste, M. (1998) · Journal of Bioenergetics and Biomembranes · doi:10.1023/a:1020547225398 · Cited by 63 · see citing works
Surface biosignatures of exo-Earths: Remote detection of extraterrestrial life
Hegde, S., Paulino‐Lima, I. G., Kent, R., Kaltenegger, L., & Rothschild, L. J. (2015) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1421237112 · Cited by 59 · see citing works
Spectral Fingerprints of Earth-like Planets Around FGK Stars
Rugheimer, S., Kaltenegger, L., Zsom, A., Segura, A., & Sasselov, D. D. (2012) · DSpace@MIT (Massachusetts Institute of Technology) · Cited by 61 · see citing works
Perryman, M. A. C. (2011) · Cambridge University Press eBooks · doi:10.1017/cbo9780511994852.011 · Cited by 71 · see citing works
Near-Infrared Detection of Potential Evidence for Microscopic Organisms on Europa
Dalton, J. B., Mogul, R., Kagawa, H. K., Chan, S. L., & Jamieson, C. S. (2003) · Astrobiology · doi:10.1089/153110703322610618 · Cited by 60 · see citing works
Using Deep Space Climate Observatory Measurements to Study the Earth as an Exoplanet
Jiang, J. H., Zhai, A. J., Herman, J. R., Zhai, C., Hu, R., Su, H., Natraj, V., Li, J., Xu, F., & Yung, Y. L. (2018) · The Astronomical Journal · doi:10.3847/1538-3881/aac6e2 · Cited by 60 · see citing works
Lenton, T. M., Dutreuil, S., & Latour, B. (2020) · The Anthropocene Review · doi:10.1177/2053019620918939 · Cited by 60 · see citing works
VIEWS FROMEPOXI: COLORS IN OUR SOLAR SYSTEM AS AN ANALOG FOR EXTRASOLAR PLANETS
Crow, C. A., McFadden, L. A., Robinson, T. D., Meadows, V., Livengood, T. A., Hewagama, T., Barry, R. K., Deming, D., Lisse, C. M., & Wellnitz, D. D. (2011) · The Astrophysical Journal · doi:10.1088/0004-637x/729/2/130 · Cited by 59 · see citing works
Globally Integrated Measurements of the Earth’s Visible Spectral Albedo
Montanes‐Rodriguez, P., Palle, E., Goode, P. R., Hickey, J., & Koonin, S. E. (2005) · The Astrophysical Journal · doi:10.1086/431420 · Cited by 57 · see citing works
Detecting Life‐bearing Extrasolar Planets with Space Telescopes
Beckwith, S. V. W. (2008) · The Astrophysical Journal · doi:10.1086/590466 · Cited by 56 · see citing works
First fullyab initiopotential energy surface of methane with a spectroscopic accuracy
Nikitin, A. V., Rey, M., & Tyuterev, V. G. (2016) · The Journal of Chemical Physics · doi:10.1063/1.4961973 · Cited by 53 · see citing works
- Authors
- Sagan, C., Thompson, W. R., Carlson, R., Gurnett, D., & Hord, C.
- Affiliations
- Cornell University (US)
- Jet Propulsion Laboratory (US)
- University of Iowa (US)
- University of Colorado Boulder (US)
- Venue
- Nature
- Published
- 1993-10
- Volume
- 365
- Issue
- 6448
- Pages
- 715-721
- ISSN
- 0028-0836 (ISSN-L)
- 1476-4687
- OpenAlex
- W1972716255
- Cited by
- 507
- References
- 28
- Citations by year
- 2026: 14 · 2025: 26 · 2024: 25 · 2023: 47 · 2022: 13 · 2021: 28 · 2020: 19 · 2019: 51 · 2018: 57 · 2017: 19 · 2016: 11 · 2015: 11 · 2014: 10 · 2013: 14 · 2012: 11
- FWCI
- 6.61
- Type
- journal article
- Language
- en
- Open access
- closed
- Licence
- www.springer.com/tdm (tdm)
- Locations
- Nature (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Space Science and Extraterrestrial Life
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Planetary Science and Exploration
- Physical Sciences › Earth and Planetary Sciences › Atmospheric Science › Earth Systems and Cosmic Evolution
- Keywords
- Galileo spacecraft, gaseous oxygen, atmospheric methane, thermodynamic non-equilibrium, radio transmission, extraterrestrial life detection, interplanetary spacecraft, planetary atmospheres
- MeSH terms
- Atmosphere, Extraterrestrial Environment, Methane, Oxygen, Radio Waves, Space Flight, Spectrophotometry, Infrared, Spectrophotometry, Ultraviolet, Water, Spacecraft, Earth, Planet, Exobiology
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