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Lam KWF, Csizmadia S, Astudillo-Defru N, Bonfils X, Gandolfi D, Padovan S, Esposito M, Hellier C, Hirano T, Livingston J, Murgas F, Smith AMS, Collins KA, Mathur S, Garcia RA, Howell SB, Santos NC, Dai F, Ricker GR, Vanderspek R, Latham DW, Seager S, Winn JN, Jenkins JM, Albrecht S, Almenara JM, Artigau E, Barragán O, Bouchy F, Cabrera J, Charbonneau D, Chaturvedi P, Chaushev A, Christiansen JL, Cochran WD, De Meideiros JR, Delfosse X, Díaz RF, Doyon R, Eigmüller P, Figueira P, Forveille T, Fridlund M, Gaisné G, Goffo E, Georgieva I, Grziwa S, Guenther E, Hatzes AP, Johnson MC, Kabáth P, Knudstrup E, Korth J, Lewin P, Lissauer JJ, Lovis C, Luque R, Melo C, Morgan EH, Morris R, Mayor M, Narita N, Osborne HLM, Palle E, Pepe F, Persson CM, Quinn SN, Rauer H, Redfield S, Schlieder JE, Ségransan D, Serrano LM, Smith JC, Šubjak J, Twicken JD, Udry S, Van Eylen V, Vezie M. GJ 367b: A dense, ultrashort-period sub-Earth planet transiting a nearby red dwarf star. Science 2021; 374:1271-1275. [PMID: 34855492 DOI: 10.1126/science.aay3253] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Kristine W F Lam
- Centre for Astronomy and Astrophysics, Technical University Berlin, 10585 Berlin, Germany.,Institute of Planetary Research, German Aerospace Center, 12489 Berlin, Germany
| | - Szilárd Csizmadia
- Institute of Planetary Research, German Aerospace Center, 12489 Berlin, Germany
| | - Nicola Astudillo-Defru
- Departamento de Matemática y Física Aplicadas, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Xavier Bonfils
- Université Grenoble Alpes, Centre national de la recherche scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, F-38000 Grenoble, France
| | - Davide Gandolfi
- Dipartimento di Fisica, Università degli Studi di Torino, I-10125, Torino, Italy
| | - Sebastiano Padovan
- Institute of Planetary Research, German Aerospace Center, 12489 Berlin, Germany.,WorkGroup Solutions GmbH at European Organisation for the Exploitation of Meteorological Satellites, 64295 Darmstadt, Germany
| | | | - Coel Hellier
- Astrophysics Group, Keele University, Staffordshire, ST5 5BG, UK
| | - Teruyuki Hirano
- Department of Earth and Planetary Sciences, Tokyo Institute of Technology, Tokyo, Japan
| | | | - Felipe Murgas
- Instituto de Astrofísica de Canarias, 38205 La Laguna, Tenerife, Spain.,Departamento de Astrofísica, Universidad de La Laguna, 38206 La Laguna, Tenerife, Spain
| | - Alexis M S Smith
- Institute of Planetary Research, German Aerospace Center, 12489 Berlin, Germany
| | - Karen A Collins
- Center for Astrophysics, Harvard and Smithsonian, Cambridge, MA, USA
| | - Savita Mathur
- Instituto de Astrofísica de Canarias, 38205 La Laguna, Tenerife, Spain.,Departamento de Astrofísica, Universidad de La Laguna, 38206 La Laguna, Tenerife, Spain
| | - Rafael A Garcia
- Institut de Recherche sur les Lois Fondamentales de l'Universe, Commissariat à l'Énergie Atomique et aux énergies alternatives, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France.,Astrophysique, Instrumentation et modélisation, Commissariat à l'Énergie Atomique et aux énergies alternatives, Centre National de la recherche scientifique, Université Paris-Saclay, Université Paris Diderot, Sorbonne Paris Cité, F-91191 Gif-sur-Yvette, France
| | | | - Nuno C Santos
- Instituto de Astrofísica e Ciênciasdo Espaço, Universidade do Porto, Centro de Astrofísica da Universidade do Porto, 4150-762 Porto, Portugal.,Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal
| | - Fei Dai
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA
| | - George R Ricker
- Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Roland Vanderspek
- Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - David W Latham
- Center for Astrophysics, Harvard and Smithsonian, Cambridge, MA, USA
| | - Sara Seager
- Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA, USA.,Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.,Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Joshua N Winn
- Department of Astrophysical Sciences, Princeton University, Princeton, NJ, USA
| | | | - Simon Albrecht
- Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Jose M Almenara
- Université Grenoble Alpes, Centre national de la recherche scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, F-38000 Grenoble, France
| | - Etienne Artigau
- Université Grenoble Alpes, Centre national de la recherche scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, F-38000 Grenoble, France
| | - Oscar Barragán
- Subdepartment of Astrophysics, Department of Physics, University of Oxford, Oxford, OX1 3RH, UK
| | - François Bouchy
- Geneva Observatory, University of Geneva, 1290 Versoix, Switzerland
| | - Juan Cabrera
- Université Grenoble Alpes, Centre national de la recherche scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, F-38000 Grenoble, France
| | - David Charbonneau
- Center for Astrophysics, Harvard and Smithsonian, Cambridge, MA, USA
| | | | - Alexander Chaushev
- Centre for Astronomy and Astrophysics, Technical University Berlin, 10585 Berlin, Germany
| | | | - William D Cochran
- Center for Planetary Systems Habitability and McDonald Observatory, The University of Texas, Austin, TX, USA
| | - José R De Meideiros
- Departamento de Física, Universidade Federal do Rio Grande do Norte, 59072-970 Natal, RN, Brazil
| | - Xavier Delfosse
- Université Grenoble Alpes, Centre national de la recherche scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, F-38000 Grenoble, France
| | - Rodrigo F Díaz
- International Center for Advanced Studies and Instituto de Ciencias Físicas (Consejo Nacional de Investigaciones Científicas y Técnicas), Escuela de Ciencia y Tecnología - Universidad Nacional de San Martín, Campus Miguelete, Buenos Aires, Argentina
| | - René Doyon
- Institut de Recherche sur les Exoplantes, Dpartement de Physique, Universit de Montral, Montral, QC, H3C 3J7, Canada
| | - Philipp Eigmüller
- Institute of Planetary Research, German Aerospace Center, 12489 Berlin, Germany
| | - Pedro Figueira
- Instituto de Astrofísica e Ciênciasdo Espaço, Universidade do Porto, Centro de Astrofísica da Universidade do Porto, 4150-762 Porto, Portugal.,European Southern Observatory, Vitacura, Santiago, Chile
| | - Thierry Forveille
- Université Grenoble Alpes, Centre national de la recherche scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, F-38000 Grenoble, France
| | - Malcolm Fridlund
- Department of Space, Earth and Environment, Chalmers University of Technology, Onsala Space Observatory, 439 92 Onsala, Sweden.,Leiden Observatory, University of Leiden, 2300 RA, Leiden, Netherlands
| | - Guillaume Gaisné
- Université Grenoble Alpes, Centre national de la recherche scientifique, Institut de Planétologie et d'Astrophysique de Grenoble, F-38000 Grenoble, France
| | - Elisa Goffo
- Dipartimento di Fisica, Università degli Studi di Torino, I-10125, Torino, Italy.,Thüringer Landessternwarte Tautenburg, D-07778 Tautenberg, Germany
| | - Iskra Georgieva
- Department of Space, Earth and Environment, Chalmers University of Technology, Onsala Space Observatory, 439 92 Onsala, Sweden
| | - Sascha Grziwa
- Rheinisches Institut für Umweltforschung an der Universität zu Köln, D-50931 Köln, Germany
| | - Eike Guenther
- Thüringer Landessternwarte Tautenburg, D-07778 Tautenberg, Germany
| | - Artie P Hatzes
- Thüringer Landessternwarte Tautenburg, D-07778 Tautenberg, Germany
| | | | - Petr Kabáth
- Astronomical Institute, Czech Academy of Sciences, 25165 Ondřejov, Czech Republic
| | - Emil Knudstrup
- Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Judith Korth
- Rheinisches Institut für Umweltforschung an der Universität zu Köln, D-50931 Köln, Germany.,Department of Space, Earth and Environment, Astronomy and Plasma Physics, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Pablo Lewin
- The Maury Lewin Astronomical Observatory, Glendora, CA, USA
| | - Jack J Lissauer
- NASA Ames Research Center, Moffett Field, CA, USA.,Geological Sciences Department, Stanford University, CA, USA
| | - Christophe Lovis
- Geneva Observatory, University of Geneva, 1290 Versoix, Switzerland
| | - Rafael Luque
- Instituto de Astrofísica de Canarias, 38205 La Laguna, Tenerife, Spain.,Departamento de Astrofísica, Universidad de La Laguna, 38206 La Laguna, Tenerife, Spain
| | - Claudio Melo
- European Southern Observatory, Vitacura, Santiago, Chile
| | - Edward H Morgan
- Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Robert Morris
- NASA Ames Research Center, Moffett Field, CA, USA.,Search for Extraterrestrial Intelligence Institute, Mountain View, CA, USA
| | - Michel Mayor
- Geneva Observatory, University of Geneva, 1290 Versoix, Switzerland
| | - Norio Narita
- Instituto de Astrofísica de Canarias, 38205 La Laguna, Tenerife, Spain.,Komaba Institute for Science, The University of Tokyo, Tokyo, Japan.,Japan Science and Technology Agency, Precursory Research for Embryonic Science and Technology, Tokyo, Japan.,Astrobiology Center, Tokyo, Japan
| | - Hannah L M Osborne
- Mullard Space Science Laboratory, University College London, Dorking, Surrey, RH5 6NT, UK
| | - Enric Palle
- Instituto de Astrofísica de Canarias, 38205 La Laguna, Tenerife, Spain.,Departamento de Astrofísica, Universidad de La Laguna, 38206 La Laguna, Tenerife, Spain
| | - Francesco Pepe
- Geneva Observatory, University of Geneva, 1290 Versoix, Switzerland
| | - Carina M Persson
- Department of Space, Earth and Environment, Chalmers University of Technology, Onsala Space Observatory, 439 92 Onsala, Sweden
| | - Samuel N Quinn
- Center for Astrophysics, Harvard and Smithsonian, Cambridge, MA, USA
| | - Heike Rauer
- Centre for Astronomy and Astrophysics, Technical University Berlin, 10585 Berlin, Germany.,Institute of Planetary Research, German Aerospace Center, 12489 Berlin, Germany.,Institute of Geological Sciences, Freie Universität Berlin, D-12249 Berlin, Germany
| | - Seth Redfield
- Astronomy Department and Van Vleck Observatory, Wesleyan University, Middletown, CT, USA
| | | | - Damien Ségransan
- Geneva Observatory, University of Geneva, 1290 Versoix, Switzerland
| | - Luisa M Serrano
- Dipartimento di Fisica, Università degli Studi di Torino, I-10125, Torino, Italy
| | - Jeffrey C Smith
- NASA Ames Research Center, Moffett Field, CA, USA.,Search for Extraterrestrial Intelligence Institute, Mountain View, CA, USA
| | - Ján Šubjak
- Astronomical Institute, Czech Academy of Sciences, 25165 Ondřejov, Czech Republic.,Astronomical Institute of Charles University, 180 00 Prague, Czech Republic
| | - Joseph D Twicken
- NASA Ames Research Center, Moffett Field, CA, USA.,Search for Extraterrestrial Intelligence Institute, Mountain View, CA, USA
| | - Stéphane Udry
- Geneva Observatory, University of Geneva, 1290 Versoix, Switzerland
| | - Vincent Van Eylen
- Mullard Space Science Laboratory, University College London, Dorking, Surrey, RH5 6NT, UK
| | - Michael Vezie
- Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA, USA
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O2- and CO-rich Atmospheres for Potentially Habitable Environments on TRAPPIST-1 Planets. ACTA ACUST UNITED AC 2020. [DOI: 10.3847/1538-4357/ab5f07] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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5
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Connecting Giant Planet Atmosphere and Interior Modeling: Constraints on Atmospheric Metal Enrichment. ACTA ACUST UNITED AC 2019. [DOI: 10.3847/2041-8213/ab1137] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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6
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7
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8
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HD 202772A b: A Transiting Hot Jupiter around a Bright, Mildly Evolved Star in a Visual Binary Discovered by TESS. ACTA ACUST UNITED AC 2019. [DOI: 10.3847/1538-3881/aaf1b7] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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9
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Kane SR, Ceja AY, Way MJ, Quintana EV. CLIMATE MODELING OF A POTENTIAL EXOVENUS. THE ASTROPHYSICAL JOURNAL 2018; 869:46. [PMID: 30636775 PMCID: PMC6326386 DOI: 10.3847/1538-4357/aaec68] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The planetary mass and radius sensitivity of exoplanet discovery capabilities has reached into the terrestrial regime. The focus of such investigations is to search within the Habitable Zone where a modern Earth-like atmosphere may be a viable comparison. However, the detection bias of the transit and radial velocity methods lies close to the host star where the received flux at the planet may push the atmosphere into a runaway greenhouse state. One such exoplanet discovery, Kepler-1649b, receives a similar flux from its star as modern Venus does from the Sun, and so was categorized as a possible exoVenus. Here we discuss the planetary parameters of Kepler-1649b with relation to Venus to establish its potential as a Venus analog. We utilize the general circulation model ROCKE-3D to simulate the evolution of the surface temperature of Kepler-1649b under various assumptions, including relative atmospheric abundances. We show that in all our simulations the atmospheric model rapidly diverges from temperate surface conditions towards a runaway greenhouse with rapidly escalating surface temperatures. We calculate transmission spectra for the evolved atmosphere and discuss these spectra within the context of the James Webb Space Telescope (JWST) Near-Infrared Spectrograph (NIRSpec) capabilities. We thus demonstrate the detectability of the key atmospheric signatures of possible runaway greenhouse transition states and outline the future prospects of characterizing potential Venus analogs.
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Affiliation(s)
- Stephen R Kane
- Department of Earth Sciences, University of California, Riverside, CA 92521, USA
| | - Alma Y Ceja
- Department of Earth Sciences, University of California, Riverside, CA 92521, USA
| | - Michael J Way
- NASA Goddard Institute for Space Studies, New York, NY 10025, USA
- Department of Physics and Astronomy, Uppsala University, Uppsala, SE-75120, Sweden
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Edwards B, Rice M, Zingales T, Tessenyi M, Waldmann I, Tinetti G, Pascale E, Savini G, Sarkar S. Exoplanet spectroscopy and photometry with the Twinkle space telescope. EXPERIMENTAL ASTRONOMY 2018; 47:29-63. [PMID: 32684665 PMCID: PMC7357794 DOI: 10.1007/s10686-018-9611-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 11/14/2018] [Indexed: 06/11/2023]
Abstract
The Twinkle space telescope has been designed for the characterisation of exoplanets and Solar System objects. Operating in a low Earth, Sun-synchronous orbit, Twinkle is equipped with a 45 cm telescope and visible (0.4 - 1 μm) and infrared (1.3 - 4.5 μm) spectrometers which can be operated simultaneously. Twinkle is a general observatory which will provide on-demand observations of a wide variety of targets within wavelength ranges that are currently not accessible using other space telescopes or accessible only to oversubscribed observatories in the short-term future. Here we explore the ability of Twinkle's spectrometers to characterise the currently-known exoplanets. We study the spectral resolution achievable by combining multiple observations for various planetary and stellar types. We also simulate spectral retrievals for some well-known planets (HD 209458 b, GJ 3470 b and 55 Cnc e). From the exoplanets known today, we find that with a single transit or eclipse, Twinkle could probe 89 planets at low spectral resolution (R < 20) as well as 12 planets at higher resolution (R > 20) in channel 1 (1.3 - 4.5 μm). With 10 observations, the atmospheres of 144 planets could be characterised with R <20 and 81 at higher resolutions. Upcoming surveys will reveal thousands of new exoplanets, many of which will be located within Twinkle's field of regard. TESS in particular is predicted to discover many targets around bright stars which will be suitable for follow-up observations. We include these anticipated planets and find that the number of planets Twinkle could observe in the near infrared in a single transit or eclipse increases R > 20. By stacking 10 transits, there are 1185 potential targets for study at R < 20 as well as 388 planets at higher resolutions. The majority of targets are found to be large gaseous planets although by stacking multiple observations smaller planets around bright stars (e.g. 55 Cnc e) could be observed with Twinkle. Photometry and low resolution spectroscopy with Twinkle will be useful to refine planetary, stellar and orbital parameters, monitor stellar activity through time and search for transit time and duration variations (TTVs and TDVs). Refinement of these parameters could be used to in the planning of observations with larger space-based observatories such as JWST and ARIEL. For planets orbiting very bright stars, Twinkle observations at higher spectral resolution will enable us to probe the chemical and thermal properties of an atmosphere. Simultaneous coverage across a wide wavelength range will reduce the degeneracies seen with Hubble and provide access to detections of a wide range molecules. There is the potential to revisit them many times over the mission lifetime to detect variations in cloud cover.
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Affiliation(s)
- Billy Edwards
- Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT UK
| | - Malena Rice
- Department of Astronomy, Yale University, Steinbach Hall, New Haven, CT 06511 USA
| | | | - Marcell Tessenyi
- Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT UK
- Blue Skies Space Ltd., 69 Wilson Street, London, EC2A 2BB UK
| | - Ingo Waldmann
- Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT UK
| | - Giovanna Tinetti
- Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT UK
- Blue Skies Space Ltd., 69 Wilson Street, London, EC2A 2BB UK
| | - Enzo Pascale
- Dipartimento di Fisica, La Sapienza Universita di Roma, Piazzale Aldo Moro 2, 00185 Roma, Italy
- School of Physics and Astronomy, Cardiff University, Queens Buildings, The Parade, Cardiff, CF24 3AA UK
| | - Giorgio Savini
- Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT UK
- Blue Skies Space Ltd., 69 Wilson Street, London, EC2A 2BB UK
| | - Subhajit Sarkar
- School of Physics and Astronomy, Cardiff University, Queens Buildings, The Parade, Cardiff, CF24 3AA UK
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11
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Evolved Climates and Observational Discriminants for the TRAPPIST-1 Planetary System. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/1538-4357/aae36a] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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12
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The KELT Follow-up Network and Transit False-positive Catalog: Pre-vetted False Positives for TESS. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/1538-3881/aae582] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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13
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14
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New Rotation Period Measurements for M Dwarfs in the Southern Hemisphere: An Abundance of Slowly Rotating, Fully Convective Stars. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/1538-3881/aad73b] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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15
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16
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17
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Buildup of Abiotic Oxygen and Ozone in Moist Atmospheres of Temperate Terrestrial Exoplanets and Its Impact on the Spectral Fingerprint in Transit Observations. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/1538-4357/aaca36] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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18
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Fujii Y, Angerhausen D, Deitrick R, Domagal-Goldman S, Grenfell JL, Hori Y, Kane SR, Pallé E, Rauer H, Siegler N, Stapelfeldt K, Stevenson KB. Exoplanet Biosignatures: Observational Prospects. ASTROBIOLOGY 2018; 18:739-778. [PMID: 29938537 PMCID: PMC6016572 DOI: 10.1089/ast.2017.1733] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 03/13/2018] [Indexed: 05/04/2023]
Abstract
Exoplanet hunting efforts have revealed the prevalence of exotic worlds with diverse properties, including Earth-sized bodies, which has fueled our endeavor to search for life beyond the Solar System. Accumulating experiences in astrophysical, chemical, and climatological characterization of uninhabitable planets are paving the way to characterization of potentially habitable planets. In this paper, we review our possibilities and limitations in characterizing temperate terrestrial planets with future observational capabilities through the 2030s and beyond, as a basis of a broad range of discussions on how to advance "astrobiology" with exoplanets. We discuss the observability of not only the proposed biosignature candidates themselves but also of more general planetary properties that provide circumstantial evidence, since the evaluation of any biosignature candidate relies on its context. Characterization of temperate Earth-sized planets in the coming years will focus on those around nearby late-type stars. The James Webb Space Telescope (JWST) and later 30-meter-class ground-based telescopes will empower their chemical investigations. Spectroscopic studies of potentially habitable planets around solar-type stars will likely require a designated spacecraft mission for direct imaging, leveraging technologies that are already being developed and tested as part of the Wide Field InfraRed Survey Telescope (WFIRST) mission. Successful initial characterization of a few nearby targets will be an important touchstone toward a more detailed scrutiny and a larger survey that are envisioned beyond 2030. The broad outlook this paper presents may help develop new observational techniques to detect relevant features as well as frameworks to diagnose planets based on the observables. Key Words: Exoplanets-Biosignatures-Characterization-Planetary atmospheres-Planetary surfaces. Astrobiology 18, 739-778.
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Affiliation(s)
- Yuka Fujii
- NASA Goddard Institute for Space Studies, New York, New York, USA
- Earth-Life Science Institute, Tokyo Institute of Technology, Ookayama, Meguro, Tokyo, Japan
| | - Daniel Angerhausen
- CSH Fellow for Exoplanetary Astronomy, Center for Space and Habitability (CSH), Universität Bern, Bern, Switzerland
- Blue Marble Space Institute of Science, Seattle, Washington, USA
| | - Russell Deitrick
- Department of Astronomy, University of Washington, Seattle, Washington, USA
- NASA Astrobiology Institute's Virtual Planetary Laboratory
| | - Shawn Domagal-Goldman
- NASA Astrobiology Institute's Virtual Planetary Laboratory
- NASA Goddard Space Flight Center, Greenbelt, Maryland, USA
| | - John Lee Grenfell
- Department of Extrasolar Planets and Atmospheres (EPA), Institute of Planetary Research, German Aerospace Centre (DLR), Berlin, Germany
| | - Yasunori Hori
- Astrobiology Center, National Institutes of Natural Sciences (NINS), Mitaka, Tokyo, Japan
| | - Stephen R. Kane
- Department of Earth Sciences, University of California, Riverside, California, USA
| | - Enric Pallé
- Instituto de Astrofísica de Canarias, La Laguna, Tenerife, Spain
- Departamento de Astrofísica, Universidad de La Laguna, Tenerife, Spain
| | - Heike Rauer
- Department of Extrasolar Planets and Atmospheres (EPA), Institute of Planetary Research, German Aerospace Centre (DLR), Berlin, Germany
- Center for Astronomy and Astrophysics, Berlin Institute of Technology, Berlin, Germany
| | - Nicholas Siegler
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
- NASA Exoplanet Exploration Office
| | - Karl Stapelfeldt
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
- NASA Exoplanet Exploration Office
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Schwieterman EW, Kiang NY, Parenteau MN, Harman CE, DasSarma S, Fisher TM, Arney GN, Hartnett HE, Reinhard CT, Olson SL, Meadows VS, Cockell CS, Walker SI, Grenfell JL, Hegde S, Rugheimer S, Hu R, Lyons TW. Exoplanet Biosignatures: A Review of Remotely Detectable Signs of Life. ASTROBIOLOGY 2018; 18:663-708. [PMID: 29727196 PMCID: PMC6016574 DOI: 10.1089/ast.2017.1729] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 12/10/2017] [Indexed: 05/04/2023]
Abstract
In the coming years and decades, advanced space- and ground-based observatories will allow an unprecedented opportunity to probe the atmospheres and surfaces of potentially habitable exoplanets for signatures of life. Life on Earth, through its gaseous products and reflectance and scattering properties, has left its fingerprint on the spectrum of our planet. Aided by the universality of the laws of physics and chemistry, we turn to Earth's biosphere, both in the present and through geologic time, for analog signatures that will aid in the search for life elsewhere. Considering the insights gained from modern and ancient Earth, and the broader array of hypothetical exoplanet possibilities, we have compiled a comprehensive overview of our current understanding of potential exoplanet biosignatures, including gaseous, surface, and temporal biosignatures. We additionally survey biogenic spectral features that are well known in the specialist literature but have not yet been robustly vetted in the context of exoplanet biosignatures. We briefly review advances in assessing biosignature plausibility, including novel methods for determining chemical disequilibrium from remotely obtainable data and assessment tools for determining the minimum biomass required to maintain short-lived biogenic gases as atmospheric signatures. We focus particularly on advances made since the seminal review by Des Marais et al. The purpose of this work is not to propose new biosignature strategies, a goal left to companion articles in this series, but to review the current literature, draw meaningful connections between seemingly disparate areas, and clear the way for a path forward. Key Words: Exoplanets-Biosignatures-Habitability markers-Photosynthesis-Planetary surfaces-Atmospheres-Spectroscopy-Cryptic biospheres-False positives. Astrobiology 18, 663-708.
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Affiliation(s)
- Edward W. Schwieterman
- Department of Earth Sciences, University of California, Riverside, California
- NASA Postdoctoral Program, Universities Space Research Association, Columbia, Maryland
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
- Blue Marble Space Institute of Science, Seattle, Washington
| | - Nancy Y. Kiang
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
- NASA Goddard Institute for Space Studies, New York, New York
| | - Mary N. Parenteau
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
- NASA Ames Research Center, Exobiology Branch, Mountain View, California
| | - Chester E. Harman
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
- NASA Goddard Institute for Space Studies, New York, New York
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York
| | - Shiladitya DasSarma
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland
- Institute of Marine and Environmental Technology, University System of Maryland, Baltimore, Maryland
| | - Theresa M. Fisher
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona
| | - Giada N. Arney
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
- Planetary Systems Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Hilairy E. Hartnett
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona
- School of Molecular Sciences, Arizona State University, Tempe, Arizona
| | - Christopher T. Reinhard
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia
| | - Stephanie L. Olson
- Department of Earth Sciences, University of California, Riverside, California
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
| | - Victoria S. Meadows
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
- Astronomy Department, University of Washington, Seattle, Washington
| | - Charles S. Cockell
- University of Edinburgh School of Physics and Astronomy, Edinburgh, United Kingdom
- UK Centre for Astrobiology, Edinburgh, United Kingdom
| | - Sara I. Walker
- Blue Marble Space Institute of Science, Seattle, Washington
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona
- Beyond Center for Fundamental Concepts in Science, Arizona State University, Tempe, Arizona
- ASU-Santa Fe Institute Center for Biosocial Complex Systems, Arizona State University, Tempe, Arizona
| | - John Lee Grenfell
- Institut für Planetenforschung (PF), Deutsches Zentrum für Luft und Raumfahrt (DLR), Berlin, Germany
| | - Siddharth Hegde
- Carl Sagan Institute, Cornell University, Ithaca, New York
- Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, New York
| | - Sarah Rugheimer
- Department of Earth and Environmental Sciences, University of St. Andrews, St. Andrews, United Kingdom
| | - Renyu Hu
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California
| | - Timothy W. Lyons
- Department of Earth Sciences, University of California, Riverside, California
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
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Meadows VS, Reinhard CT, Arney GN, Parenteau MN, Schwieterman EW, Domagal-Goldman SD, Lincowski AP, Stapelfeldt KR, Rauer H, DasSarma S, Hegde S, Narita N, Deitrick R, Lustig-Yaeger J, Lyons TW, Siegler N, Grenfell JL. Exoplanet Biosignatures: Understanding Oxygen as a Biosignature in the Context of Its Environment. ASTROBIOLOGY 2018; 18:630-662. [PMID: 29746149 PMCID: PMC6014580 DOI: 10.1089/ast.2017.1727] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 12/15/2017] [Indexed: 05/04/2023]
Abstract
We describe how environmental context can help determine whether oxygen (O2) detected in extrasolar planetary observations is more likely to have a biological source. Here we provide an in-depth, interdisciplinary example of O2 biosignature identification and observation, which serves as the prototype for the development of a general framework for biosignature assessment. Photosynthetically generated O2 is a potentially strong biosignature, and at high abundance, it was originally thought to be an unambiguous indicator for life. However, as a biosignature, O2 faces two major challenges: (1) it was only present at high abundance for a relatively short period of Earth's history and (2) we now know of several potential planetary mechanisms that can generate abundant O2 without life being present. Consequently, our ability to interpret both the presence and absence of O2 in an exoplanetary spectrum relies on understanding the environmental context. Here we examine the coevolution of life with the early Earth's environment to identify how the interplay of sources and sinks may have suppressed O2 release into the atmosphere for several billion years, producing a false negative for biologically generated O2. These studies suggest that planetary characteristics that may enhance false negatives should be considered when selecting targets for biosignature searches. We review the most recent knowledge of false positives for O2, planetary processes that may generate abundant atmospheric O2 without a biosphere. We provide examples of how future photometric, spectroscopic, and time-dependent observations of O2 and other aspects of the planetary environment can be used to rule out false positives and thereby increase our confidence that any observed O2 is indeed a biosignature. These insights will guide and inform the development of future exoplanet characterization missions. Key Words: Biosignatures-Oxygenic photosynthesis-Exoplanets-Planetary atmospheres. Astrobiology 18, 630-662.
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Affiliation(s)
- Victoria S. Meadows
- Department of Astronomy, University of Washington, Seattle, Washington
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
| | - Christopher T. Reinhard
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
| | - Giada N. Arney
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
- Planetary Systems Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Mary N. Parenteau
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
- NASA Ames Research Center, Exobiology Branch, Mountain View, California
| | - Edward W. Schwieterman
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
- Department of Earth Sciences, University of California, Riverside, California
- NASA Postdoctoral Program, Universities Space Research Association, Columbia, Maryland
- Blue Marble Space Institute of Science, Seattle, Washington
| | - Shawn D. Domagal-Goldman
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
- Planetary Environments Laboratory, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Andrew P. Lincowski
- Department of Astronomy, University of Washington, Seattle, Washington
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
| | - Karl R. Stapelfeldt
- NASA Exoplanet Exploration Program, Jet Propulsion Laboratory/California Institute of Technology, Pasadena, California
| | - Heike Rauer
- German Aerospace Center, Institute of Planetary Research, Extrasolar Planets and Atmospheres, Berlin, Germany
| | - Shiladitya DasSarma
- Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, Maryland
- Institute of Marine and Environmental Technology, University System of Baltimore, Maryland
| | - Siddharth Hegde
- Carl Sagan Institute, Cornell University, Ithaca, New York
- Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, New York
| | - Norio Narita
- Department of Astronomy, The University of Tokyo, Tokyo, Japan
- Astrobiology Center, NINS, Tokyo, Japan
- National Astronomical Observatory of Japan, NINS, Tokyo, Japan
| | - Russell Deitrick
- Department of Astronomy, University of Washington, Seattle, Washington
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
| | - Jacob Lustig-Yaeger
- Department of Astronomy, University of Washington, Seattle, Washington
- NASA Astrobiology Institute, Virtual Planetary Laboratory Team, Seattle, Washington
| | - Timothy W. Lyons
- NASA Astrobiology Institute, Alternative Earths Team, Riverside, California
- Department of Earth Sciences, University of California, Riverside, California
| | - Nicholas Siegler
- NASA Exoplanet Exploration Program, Jet Propulsion Laboratory/California Institute of Technology, Pasadena, California
| | - J. Lee Grenfell
- German Aerospace Center, Institute of Planetary Research, Extrasolar Planets and Atmospheres, Berlin, Germany
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An Improved Transit Measurement for a 2.4 R ⊕ Planet Orbiting A Bright Mid-M Dwarf K2–28. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/1538-3881/aabd75] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Strategies for Constraining the Atmospheres of Temperate Terrestrial Planets with
JWST. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/2041-8213/aab896] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Witze A. NASA’s next exoplanet hunter will seek worlds close to home. Nature 2018; 556:158-159. [DOI: 10.1038/d41586-018-03354-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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25
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Modules for Experiments in Stellar Astrophysics (${\mathtt{M}}{\mathtt{E}}{\mathtt{S}}{\mathtt{A}}$): Convective Boundaries, Element Diffusion, and Massive Star Explosions. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/1538-4365/aaa5a8] [Citation(s) in RCA: 789] [Impact Index Per Article: 131.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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27
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Campante TL. On the detectability of solar-like oscillations with the NASA TESS mission. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201716001006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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28
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Lund MN, Handberg R, Kjeldsen H, Chaplin WJ, Christensen-Dalsgaard J. Data preparation for asteroseismology with TESS. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201716001005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Toward Space-like Photometric Precision from the Ground with Beam-shaping Diffusers. ACTA ACUST UNITED AC 2017. [DOI: 10.3847/1538-4357/aa88aa] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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O’Malley-James JT, Kaltenegger L. UV surface habitability of the TRAPPIST-1 system. ACTA ACUST UNITED AC 2017. [DOI: 10.1093/mnrasl/slx047] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Accurate Empirical Radii and Masses of Planets and Their Host Stars with Gaia Parallaxes. ACTA ACUST UNITED AC 2017. [DOI: 10.3847/1538-3881/aa5df3] [Citation(s) in RCA: 231] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Conod U, Blind N, Wildi F, Pepe F. Adaptive optics for high resolution spectroscopy: a direct application with the future NIRPS spectrograph. ACTA ACUST UNITED AC 2016. [DOI: 10.1117/12.2233651] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
| | | | | | - F. Pepe
- Univ. of Geneva (Switzerland)
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Schwieterman EW, Meadows VS, Domagal-Goldman SD, Deming D, Arney GN, Luger R, Harman CE, Misra A, Barnes R. IDENTIFYING PLANETARY BIOSIGNATURE IMPOSTORS: SPECTRAL FEATURES OF CO AND O 4 RESULTING FROM ABIOTIC O 2/O 3 PRODUCTION. THE ASTROPHYSICAL JOURNAL. LETTERS 2016; Volume 819:L34. [PMID: 30147857 PMCID: PMC6108182 DOI: 10.3847/2041-8205/819/1/l13] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
O2 and O3 have been long considered the most robust individual biosignature gases in a planetary atmosphere, yet multiple mechanisms that may produce them in the absence of life have been described. However, these abiotic planetary mechanisms modify the environment in potentially identifiable ways. Here we briefly discuss two of the most detectable spectral discriminants for abiotic O2/O3: CO and O4. We produce the first explicit self-consistent simulations of these spectral discriminants as they may be seen by James Webb Space Telescope (JWST). If JWST-NIRISS and/or NIRSpec observe CO (2.35, 4.6 μm) in conjunction with CO2 (1.6, 2.0, 4.3 μm) in the transmission spectrum of a terrestrial planet it could indicate robust CO2 photolysis and suggest that a future detection of O2 or O3 might not be biogenic. Strong O4 bands seen in transmission at 1.06 and 1.27 μm could be diagnostic of a post-runaway O2-dominated atmosphere from massive H-escape. We find that for these false positive scenarios, CO at 2.35 μm, CO2 at 2.0 and 4.3 μm, and O4 at 1.27 μm are all stronger features in transmission than O2/O3 and could be detected with S/Ns ≳ 3 for an Earth-size planet orbiting a nearby M dwarf star with as few as 10 transits, assuming photon-limited noise. O4 bands could also be sought in UV/VIS/NIR reflected light (at 0.345, 0.36, 0.38, 0.445, 0.475, 0.53, 0.57, 0.63, 1.06, and 1.27 μm) by a next generation direct-imaging telescope such as LUVOIR/HDST or HabEx and would indicate an oxygen atmosphere too massive to be biologically produced.
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Affiliation(s)
- Edward W Schwieterman
- Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195, USA
- NASA Astrobiology Institute's Virtual Planetary Laboratory, Seattle, WA 981195, USA
- Astrobiology Program, University of Washington, Seattle, WA 98195, USA
| | - Victoria S Meadows
- Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195, USA
- NASA Astrobiology Institute's Virtual Planetary Laboratory, Seattle, WA 981195, USA
- Astrobiology Program, University of Washington, Seattle, WA 98195, USA
| | - Shawn D Domagal-Goldman
- NASA Astrobiology Institute's Virtual Planetary Laboratory, Seattle, WA 981195, USA
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - Drake Deming
- NASA Astrobiology Institute's Virtual Planetary Laboratory, Seattle, WA 981195, USA
- Department of Astronomy, University of Maryland, College Park, MD 20742, USA
| | - Giada N Arney
- Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195, USA
- NASA Astrobiology Institute's Virtual Planetary Laboratory, Seattle, WA 981195, USA
- Astrobiology Program, University of Washington, Seattle, WA 98195, USA
| | - Rodrigo Luger
- Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195, USA
- NASA Astrobiology Institute's Virtual Planetary Laboratory, Seattle, WA 981195, USA
- Astrobiology Program, University of Washington, Seattle, WA 98195, USA
| | - Chester E Harman
- NASA Astrobiology Institute's Virtual Planetary Laboratory, Seattle, WA 981195, USA
- Geosciences Department, Pennsylvania State University, University Park, PA 16802, USA
- Pennsylvania State Astrobiology Research Center, 2217 Earth and Engineering Sciences Building, University Park, PA 16802, USA
- Center for Exoplanets and Habitable Worlds, Pennsylvania State University, University Park, PA 16802, USA
| | - Amit Misra
- Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195, USA
- NASA Astrobiology Institute's Virtual Planetary Laboratory, Seattle, WA 981195, USA
- Astrobiology Program, University of Washington, Seattle, WA 98195, USA
| | - Rory Barnes
- Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195, USA
- NASA Astrobiology Institute's Virtual Planetary Laboratory, Seattle, WA 981195, USA
- Astrobiology Program, University of Washington, Seattle, WA 98195, USA
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Dalba PA, Muirhead PS, Fortney JJ, Hedman MM, Nicholson PD, Veyette MJ. THE TRANSIT TRANSMISSION SPECTRUM OF A COLD GAS GIANT PLANET. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/0004-637x/814/2/154] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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