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Annual Review of Earth and Planetary Sciences

Volume 47, 2019

Exoplanet Clouds

Abstract

Clouds, which are common features in Earth's atmosphere, form in atmospheres of planets that orbit other stars than our Sun, in so-called extrasolar planets or exoplanets. Exoplanet atmospheres can be chemically extremely rich. Exoplanet clouds are therefore composed of a mix of materials that changes throughout the atmosphere. They affect atmospheres through element depletion and through absorption and scattering; hence, they have a profound impact on an atmosphere's energy budget. While astronomical observations point us to the presence of extrasolar clouds and make first suggestions on particle size and material composition, we require fundamental and complex modeling work to merge the individual observations into a coherent picture. Part of this work includes developing an understanding of cloud formation in nonterrestrial environments.

  • ▪  Exoplanet atmospheres exhibit a wide chemical diversity that enables the formation of mineral clouds in contrast to the predominant water clouds on Earth.
  • ▪  Clouds consume elements, causing specific atoms and molecules to drop in abundance. Transport processes such as gravitational settling or advection delocalize this process.
  • ▪  Extrasolar planets can have extreme weather conditions where day- and nightside temperatures vary hugely. This affects cloud formation, and hence the cloud coverage and atmosphere's appearance can change dramatically.
  • ▪  Dynamic extrasolar clouds develop intracloud lightning, and electric circuits may occur on more local, smaller scales in giant exoplanets compared to smaller, Earth-like planets with less dramatic hydrodynamics.

Keyword(s): atmospheres, clouds, clusters, complex, condensation, exoplanets, modeling, weather
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2019-05-30
2024-05-23
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Literature Cited

  1. Airapetian VS, Glocer A, Gronoff G, Hébrard E, Danchi W 2016. Prebiotic chemistry and atmospheric warming of early Earth by an active young Sun. Nat. Geosci. 9:452–55
     [Google Scholar]
  2. Angelo I, Hu R 2017. A case for an atmosphere on super-Earth 55 Cancri e. Astron. J. 154:232
     [Google Scholar]
  3. Apai D, Karalidi T, Marley MS, Yang H, Flateau D et al. 2017. Zones, spots, and planetary-scale waves beating in brown dwarf atmospheres. Science 357:683–87
     [Google Scholar]
  4. Apai D, Radigan J, Buenzli E, Burrows A, Reid IN, Jayawardhana R 2013. HST spectral mapping of L/T transition brown dwarfs reveals cloud thickness variations. Astrophys. J. 768:121
     [Google Scholar]
  5. Arcangeli J, Désert JM, Line MR, Bean JL, Parmentier V et al. 2018. H− opacity and water dissociation in the dayside atmosphere of the very hot gas giant WASP-18b. Astrophys. J. Lett. 855:L30
     [Google Scholar]
  6. Ardaseva A, Rimmer PB, Waldmann I, Rocchetto M, Yurchenko SN et al. 2017. Lightning chemistry on Earth-like exoplanets. MNRAS 470:187–96
     [Google Scholar]
  7. Bilger C, Rimmer P, Helling C 2013. Small hydrocarbon molecules in cloud-forming brown dwarf and giant gas planet atmospheres. MNRAS 435:1888–903
     [Google Scholar]
  8. Blecic J, Dobbs-Dixon I, Greene T 2017. The implications of 3D thermal structure on 1D atmospheric retrieval. Astrophys. J. 848:127
     [Google Scholar]
  9. Carone L, Keppens R, Decin L, Henning T 2018. Stratosphere circulation on tidally locked exoEarths. MNRAS 473:4672–85
     [Google Scholar]
  10. Carter PJ, Leinhardt ZM, Elliott T, Walter MJ, Stewart ST 2015. Compositional evolution during rocky protoplanet accretion. Astrophys. J. 813:72
     [Google Scholar]
  11. Charnay B, Bézard B, Baudino JL, Bonnefoy M, Boccaletti A, Galicher R 2018. A self-consistent cloud model for brown dwarfs and young giant exoplanets: comparison with photometric and spectroscopic observations. Astrophys. J. 854:172
     [Google Scholar]
  12. Cowan NB, Machalek P, Croll B, Shekhtman LM, Burrows A et al. 2012. Thermal phase variations of WASP-12b: defying predictions. Astrophys. J. 747:82
     [Google Scholar]
  13. Crida A, Ligi R, Dorn C, Lebreton Y 2018. Mass, radius, and composition of the transiting planet 55 Cnc e: using interferometry and correlations. Astrophys. J. 860:122
     [Google Scholar]
  14. Cridland AJ, Pudritz RE, Alessi M 2016. Composition of early planetary atmospheres – I. Connecting disc astrochemistry to the formation of planetary atmospheres. MNRAS 461:3274–95
     [Google Scholar]
  15. Dang L, Cowan NB, Schwartz JC, Rauscher E, Zhang M et al. 2018. Detection of a westward hotspot offset in the atmosphere of hot gas giant CoRoT-2b. Nature Astron. 2:220–27
     [Google Scholar]
  16. de Pater I 2018. Selective enrichment of volatiles confirmed. Nat. Astron. 2:364–65
     [Google Scholar]
  17. Decin L, Richards AMS, Waters LBFM, Danilovich T, Gobrecht D et al. 2017. Study of the aluminium content in AGB winds using ALMA. Indications for the presence of gas-phase (Al2O clusters. Astron. Astrophys. 608:A55
     [Google Scholar]
  18. Demory BO, de Wit J, Lewis N, Fortney J, Zsom A et al. 2013. Inference of inhomogeneous clouds in an exoplanet atmosphere. Astrophys. J. Lett. 776:L25
     [Google Scholar]
  19. Diamond-Lowe H, Berta-Thompson Z, Charbonneau D, Kempton EMR 2018. Ground-based optical transmission spectroscopy of the small, rocky exoplanet GJ 1132b. Astron. J. 156:42
     [Google Scholar]
  20. Dobbs-Dixon I, Agol E 2013. Three-dimensional radiative-hydrodynamical simulations of the highly irradiated short-period exoplanet HD 189733b. MNRAS 435:3159–68
     [Google Scholar]
  21. Dunne EM, Gordon H, Kürten A, Almeida J, Duplissy J et al. 2016. Global atmospheric particle formation from CERN CLOUD measurements. Science 354:1119–24
     [Google Scholar]
  22. Eistrup C, Walsh C, van Dishoeck EF 2016. Setting the volatile composition of (exo)planet-building material. Does chemical evolution in disk midplanes matter? Astron. Astrophys. 595:A83
     [Google Scholar]
  23. Gadallah KAK, Mutschke H, Jäger C 2013. Analogs of solid nanoparticles as precursors of aromatic hydrocarbons. Astron. Astrophys. 554:A12
     [Google Scholar]
  24. Gao P, Marley MS, Zahnle K, Robinson TD, Lewis NK 2017. Sulfur hazes in giant exoplanet atmospheres: impacts on reflected light spectra. Astron. J. 153:139
     [Google Scholar]
  25. Glawe C, Schmidt H, Kerstein AR, Klein R 2015. XLES part I: introduction to extended large eddy simulation. arXiv:1506.04930 [physics.flu-dyn]
  26. Gobrecht D, Cristallo S, Piersanti L, Bromley ST 2017. Nucleation of small silicon carbide dust clusters in AGB stars. Astrophys. J. 840:117
     [Google Scholar]
  27. Goeres A 1996. Chemistry and thermodynamics of the nucleation in R CrB star shells. Hydrogen Deficient Stars CS Jeffery, U Heber69–81 San Francisco: Astron. Soc. Pac.
     [Google Scholar]
  28. Gustafsson B 2008. An attempt to summarize and conclude. Phys. Scripta T133:014041
     [Google Scholar]
  29. Gustafsson B, Edvardsson B, Eriksson K, Jørgensen UG, Nordlund Å, Plez B 2008. A grid of MARCS model atmospheres for late-type stars. I. Methods and general properties. Astron. Astrophys. 486:951–70
     [Google Scholar]
  30. He C, Hörst SM, Lewis NK, Yu X, Moses JI et al. 2018. Photochemical haze formation in the atmospheres of super-Earths and mini-Neptunes. Astron. J. 156:38
     [Google Scholar]
  31. Helling C, Ackerman A, Allard F, Dehn M, Hauschildt P et al. 2008a. A comparison of chemistry and dust cloud formation in ultracool dwarf model atmospheres. MNRAS 391:1854–73
     [Google Scholar]
  32. Helling C, Fomins A 2013. Modelling the formation of atmospheric dust in brown dwarfs and planetary atmospheres. Philos. Trans. R. Soc. Lond. A 371:20110581
     [Google Scholar]
  33. Helling C, Harrison RG, Honary F, Diver DA, Aplin K et al. 2016a. Atmospheric electrification in dusty, reactive gases in the Solar System and beyond. Surv. Geophys. 37:705–56
     [Google Scholar]
  34. Helling C, Jardine M, Mokler F 2011. Ionization in atmospheres of brown dwarfs and extrasolar planets. II. Dust-induced collisional ionization. Astrophys. J. 737:38
     [Google Scholar]
  35. Helling C, Klein R, Woitke P, Nowak U, Sedlmayr E 2004. Dust in brown dwarfs. IV. Dust formation and driven turbulence on mesoscopic scales. Astron. Astrophys. 423:657–75
     [Google Scholar]
  36. Helling C, Lee G, Dobbs-Dixon I, Mayne N, Amundsen DS et al. 2016b. The mineral clouds on HD 209458b and HD 189733b. MNRAS 460:855–83
     [Google Scholar]
  37. Helling C, Rimmer PB, Rodriguez-Barrera IM, Wood K, Robertson GB, Stark CR 2016c. Ionisation and discharge in cloud-forming atmospheres of brown dwarfs and extrasolar planets. Plasma Phys. Control. Fusion 58:074003
     [Google Scholar]
  38. Helling C, Vorgul I 2017. Insight into atmospheres of extrasolar planets through plasma processes. arXiv:1710.03004 [astro-ph.SR]
  39. Helling C, Woitke P, Rimmer PB, Kamp I, Thi WF, Meijerink R 2014. Disk evolution, element abundances and cloud properties of young gas giant planets. Life 4:142–73
     [Google Scholar]
  40. Helling C, Woitke P, Thi WF 2008b. Dust in brown dwarfs and extra-solar planets. I. Chemical composition and spectral appearance of quasi-static cloud layers. Astron. Astrophys. 485:547–60
     [Google Scholar]
  41. Hellmuth O 2006. Columnar modelling of nucleation burst evolution in the convective boundary layer—first results from a feasibility study; Part I: Modelling approach. Atmos. Chem. Phys. 6:4175–214
     [Google Scholar]
  42. Hodosán G, Helling C, Asensio-Torres R, Vorgul I, Rimmer PB 2016a. Lightning climatology of exoplanets and brown dwarfs guided by Solar System data. MNRAS 461:3927–47
     [Google Scholar]
  43. Hodosán G, Rimmer PB, Helling C 2016b. Is lightning a possible source of the radio emission on HAT-P-11b?. MNRAS 461:1222–26
     [Google Scholar]
  44. Hubeny I 2017. Model atmospheres of sub-stellar mass objects. MNRAS 469:841–69
     [Google Scholar]
  45. Jeong KS, Chang C, Sedlmayr E, Sülzle D 2000. Electronic structure investigation of neutral titanium oxide molecules TiO. J. Phys. B 33:3417–30
     [Google Scholar]
  46. Kataria T, Sing DK, Lewis NK, Visscher C, Showman AP et al. 2016. The atmospheric circulation of a nine-hot-Jupiter sample: probing circulation and chemistry over a wide phase space. Astrophys. J. 821:9
     [Google Scholar]
  47. Kawashima Y, Ikoma M 2018. Theoretical transmission spectra of exoplanet atmospheres with hydrocarbon haze: effect of creation, growth, and settling of haze particles. I. Model description and first results. Astrophys. J. 853:7
     [Google Scholar]
  48. Keating D, Cowan NB 2017. Revisiting the energy budget of WASP-43b: enhanced day-night heat transport. Astrophys. J. Lett. 849:L5
     [Google Scholar]
  49. Knutson HA, Charbonneau D, Allen LE, Fortney JJ, Agol E et al. 2007. A map of the day-night contrast of the extrasolar planet HD 189733b. Nature 447:183–86
     [Google Scholar]
  50. Komacek TD, Showman AP, Tan X 2017. Atmospheric circulation of hot Jupiters: dayside-nightside temperature differences. II. Comparison with observations. Astrophys. J. 835:198
     [Google Scholar]
  51. Kreidberg L, Bean JL, Désert JM, Benneke B, Deming D et al. 2014. Clouds in the atmosphere of the super-Earth exoplanet GJ1214b. Nature 505:69–72
     [Google Scholar]
  52. Krüger D, Sedlmayr E 1997. Two-fluid models for stationary dust driven winds. II. The grain size distribution in consideration of drift. Astron. Astrophys. 321:557–67
     [Google Scholar]
  53. Lee G, Dobbs-Dixon I, Helling C, Bognar K, Woitke P 2016. Dynamic mineral clouds on HD 189733b. I. 3D RHD with kinetic, non-equilibrium cloud formation. Astron. Astrophys. 594:A48
     [Google Scholar]
  54. Lines S, Mayne NJ, Boutle IA, Manners J, Lee GKH et al. 2018. Simulating the cloudy atmospheres of HD 209458 b and HD 189733 b with the 3D Met Office Unified Model. Astron. Astrophys. 615:A97
     [Google Scholar]
  55. Lothringer JD, Barman T, Koskinen T 2018. Extremely irradiated hot Jupiters: non-oxide inversions, H− opacity, and thermal dissociation of molecules. Astrophys. J. 866:27
     [Google Scholar]
  56. Määttänen A, Montmessin F, Gondet B, Scholten F, Hoffmann H et al. 2010. Mapping the mesospheric CO2 clouds on Mars: MEx/OMEGA and MEx/HRSC observations and challenges for atmospheric models. Icarus 209:452–69
     [Google Scholar]
  57. Macdonald FA, Wordsworth R 2017. Initiation of Snowball Earth with volcanic sulfur aerosol emissions. Geophys. Res. Lett. 44:1938–46
     [Google Scholar]
  58. Madhusudhan N, Bitsch B, Johansen A, Eriksson L 2017. Atmospheric signatures of giant exoplanet formation by pebble accretion. MNRAS 469:4102–15
     [Google Scholar]
  59. Mahapatra G, Helling C, Miguel Y 2017. Cloud formation in metal-rich atmospheres of hot super-Earths like 55 Cnc e and CoRoT7b. MNRAS 472:447–64
     [Google Scholar]
  60. Marley MS, Robinson TD 2015. On the cool side: modeling the atmospheres of brown dwarfs and giant planets. Annu. Rev. Astron. Astrophys. 53:279–323
     [Google Scholar]
  61. Maxted PFL, Anderson DR, Doyle AP, Gillon M, Harrington J et al. 2013. Spitzer 3.6 and 4.5 μm full-orbit light curves of WASP-18. MNRAS 428:2645–60
     [Google Scholar]
  62. Mayne NJ, Baraffe I, Acreman DM, Smith C, Browning MK et al. 2014. The unified model, a fully-compressible, non-hydrostatic, deep atmosphere global circulation model, applied to hot Jupiters. ENDGame for a HD 209458b test case. Astron. Astrophys. 561:A1
     [Google Scholar]
  63. Mendonça JM, Grimm SL, Grosheintz L, Heng K 2016. THOR: a new and flexible global circulation model to explore planetary atmospheres. Astrophys. J. 829:115
     [Google Scholar]
  64. Moses JI, Bézard B, Lellouch E, Gladstone GR, Feuchtgruber H, Allen M 2000. Photochemistry of Saturn's atmosphere. I. Hydrocarbon chemistry and comparisons with ISO observations. Icarus 143:244–98
     [Google Scholar]
  65. Moses JI, Marley MS, Zahnle K, Line MR, Fortney JJ et al. 2016. On the composition of young, directly imaged giant planets. Astrophys. J. 829:66
     [Google Scholar]
  66. Parmentier V, Line MR, Bean JL, Mansfield M, Kreidberg L et al. 2018. From thermal dissociation to condensation in the atmospheres of ultra hot Jupiters: WASP-121b in context. Astron. Astrophys. 617:A110
     [Google Scholar]
  67. Parmentier V, Showman AP, Lian Y 2013. 3D mixing in hot Jupiters atmospheres. I. Application to the day/night cold trap in HD 209458b. Astron. Astrophys. 558:A91
     [Google Scholar]
  68. Patzer ABC, Chang C, John M, Bolick U, Sülzle D 2002. Theoretical study of stationary points of the MgSiO3 molecule. Chem. Phys. Lett. 363:145–51
     [Google Scholar]
  69. Pérez-Invernón FJ, Luque A, Gordillo-Vázquez FJ 2017. Three-dimensional modeling of lightning-induced electromagnetic pulses on Venus, Jupiter, and Saturn. J. Geophys. Res. Space Phys. 122:7636–53
     [Google Scholar]
  70. Pinhas A, Madhusudhan N, Clarke C 2016. Efficiency of planetesimal ablation in giant planetary envelopes. MNRAS 463:4516–32
     [Google Scholar]
  71. Plane JMC, Flynn GJ, Määttänen A, Moores JE, Poppe AR et al. 2018. Impacts of cosmic dust on planetary atmospheres and surfaces. Space Sci. Rev. 214:23
     [Google Scholar]
  72. Pont F, Sing DK, Gibson NP, Aigrain S, Henry G, Husnoo N 2013. The prevalence of dust on the exoplanet HD 189733b from Hubble and Spitzer observations. MNRAS 432:2917–44
     [Google Scholar]
  73. Powell D, Zhang X, Gao P, Parmentier V 2018. Formation of silicate and titanium clouds on hot Jupiters. Astrophys. J. 860:18
     [Google Scholar]
  74. Rietmeijer FJM, Nuth JA III, Karner JM 1999. Metastable eutectic condensation in a Mg-Fe-SiO-H2-O2 vapor: analogs to circumstellar dust. Astrophys. J. 527:395
     [Google Scholar]
  75. Rimmer PB, Helling C 2013. Ionization in atmospheres of brown dwarfs and extrasolar planets. IV. The effect of cosmic rays. Astrophys. J. 774:108
     [Google Scholar]
  76. Rimmer PB, Helling C 2016. A chemical kinetics network for lightning and life in planetary atmospheres. Astrophys. J. Suppl. 224:9
     [Google Scholar]
  77. Rimmer PB, Helling C, Bilger C 2014. The influence of galactic cosmic rays on ion-neutral hydrocarbon chemistry in the upper atmospheres of free-floating exoplanets. Int. J. Astrobiol. 13:173–81
     [Google Scholar]
  78. Rodriguez-Barrera MI, Helling C, Wood K 2018. Environmental effects on the ionisation of brown dwarf atmospheres. Astron. Astrophys. 618:A107
     [Google Scholar]
  79. Sabri T, Gavilan L, Jäger C, Lemaire JL, Vidali G et al. 2014. Interstellar silicate analogs for grain-surface reaction experiments: gas-phase condensation and characterization of the silicate dust grains. Astrophys. J. 780:180
     [Google Scholar]
  80. Sagan C, Khare BN 1979. Tholins: organic chemistry of interstellar grains and gas. Nature 277:102–7
     [Google Scholar]
  81. Santos NC, Adibekyan V, Dorn C, Mordasini C, Noack L et al. 2017. Constraining planet structure and composition from stellar chemistry: trends in different stellar populations. Astron. Astrophys. 608:A94
     [Google Scholar]
  82. Schellart P, Trinh TNG, Buitink S, Corstanje A, Enriquez JE et al. 2015. Probing atmospheric electric fields in thunderstorms through radio emission from cosmic-ray-induced air showers. Phys. Rev. Lett. 114:165001
     [Google Scholar]
  83. Showman AP, Cooper CS, Fortney JJ, Marley MS 2008. Atmospheric circulation of hot Jupiters: three-dimensional circulation models of HD 209458b and HD 189733b with simplified forcing. Astrophys. J. 682:559–76
     [Google Scholar]
  84. Smith RNB 1990. A scheme for predicting layer clouds and their water content in a general circulation model. Q. J. R. Meteorol. Soc. 116:435–60
     [Google Scholar]
  85. Snellen IAG, de Kok RJ, le Poole R, Brogi M, Birkby J 2013. Finding extraterrestrial life using ground-based high-dispersion spectroscopy. Astrophys. J. 764:182
     [Google Scholar]
  86. Trinh TNG, Scholten O, Bonardi A, Buitink S, Corstanje A et al. 2017. Thunderstorm electric fields probed by extensive air showers through their polarized radio emission. Phys. Rev. D 95:083004
     [Google Scholar]
  87. Vorgul I, Helling C 2016. Flash ionization signature in coherent cyclotron emission from brown dwarfs. MNRAS 458:1041–56
     [Google Scholar]
  88. Woitke P, Helling C 2003. Dust in brown dwarfs. II. The coupled problem of dust formation and sedimentation. Astron. Astrophys. 399:297–313
     [Google Scholar]
  89. Woitke P, Helling C, Hunter GH, Millard JD, Turner GE et al. 2018. Equilibrium chemistry down to 100 K—impact of silicates and phyllosilicates on carbon/oxygen ratio. Astron. Astrophys. 614:A1
     [Google Scholar]
  90. Wong I, Knutson HA, Kataria T, Lewis NK, Burrows A et al. 2016. 3.6 and 4.5 μm Spitzer phase curves of the highly irradiated hot Jupiters WASP-19b and HAT-P-7b. Astrophys. J. 823:122
     [Google Scholar]
  91. Wong I, Knutson HA, Lewis NK, Kataria T, Burrows A et al. 2015. 3.6 and 4.5 μm phase curves of the highly irradiated eccentric hot Jupiter WASP-14b. Astrophys. J. 811:122
     [Google Scholar]
  92. Zellem RT, Lewis NK, Knutson HA, Griffith CA, Showman AP et al. 2014. The 4.5 μm full-orbit phase curve of the hot Jupiter HD 209458b. Astrophys. J. 790:53
     [Google Scholar]
  93. Zhang X, Showman AP 2018. Global-mean vertical tracer mixing in planetary atmospheres. Astrophys. J. 866:1
     [Google Scholar]
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Exoplanet Clouds
Annual Review of Earth and Planetary Sciences 47, 583 (2019); https://doi.org/10.1146/annurev-earth-053018-060401
/content/journals/10.1146/annurev-earth-053018-060401
/content/journals/10.1146/annurev-earth-053018-060401
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