J/ApJ/771/L45ivo://CDS.VizieR/J/ApJ/771/L45doi:10.26093/cds/vizier.17719045CDSYang J.Cowan N.B.Abbot D.S.2015-03-19T14:04:12Z2015-02-24T15:00:23ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frastronomical-modelssolar-system-planetsm-starseffective-temperatureThe habitable zone (HZ) is the circumstellar region where a planet can sustain surface liquid water. Searching for terrestrial planets in the HZ of nearby stars is the stated goal of ongoing and planned extrasolar planet surveys. Previous estimates of the inner edge of the HZ were based on one-dimensional radiative-convective models. The most serious limitation of these models is the inability to predict cloud behavior. Here we use global climate models with sophisticated cloud schemes to show that due to a stabilizing cloud feedback, tidally locked planets can be habitable at twice the stellar flux found by previous studies. This dramatically expands the HZ and roughly doubles the frequency of habitable planets orbiting red dwarf stars. At high stellar flux, strong convection produces thick water clouds near the substellar location that greatly increase the planetary albedo and reduce surface temperatures. Higher insolation produces stronger substellar convection and therefore higher albedo, making this phenomenon a stabilizing climate feedback. Substellar clouds also effectively block outgoing radiation from the surface, reducing or even completely reversing the thermal emission contrast between dayside and nightside. The presence of substellar water clouds and the resulting clement surface conditions will therefore be detectable with the James Webb Space Telescope.2013ApJ...771L..45Yhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/771/L45CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/567/A133 : Habitable zone code (Valle+, 2014)J/A+A/556/A110 : HARPS radial velocities of GJ 163 (Bonfils+, 2013)J/ApJ/770/90 : Candidate planets in the habitable zones (Gaidos, 2013)J/ApJ/767/95 : Improved parameters of smallest KIC stars (Dressing+, 2013)J/ApJ/736/L25 : Habitability of Kepler planet candidates (Kaltenegger+, 2011)J/A+A/534/A58 : HD20794, HD85512, HD192310 HARPS RVs (Pepe+, 2011)J/ApJ/716/1336 : Stability analysis of single-planet (Kopparapu+, 2010)J/ApJ/649/1010 : Habitability of known exoplanetary systems (Jones+, 2006)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/771/L45https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/771/L45http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/771/L45https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/771/L45https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/771/L45http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/771/L45GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/ApJ/771/L45/table1Climate characteristics of terrestrial planets around an M-starn_Design[jk] Additional design description (3)meta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGroup[1/6] Group number (1)meta.idintModelModel type (2)meta.notecharDesignExperimental design description (5)meta.noteTS[219/304] Global-mean surface temperature T_S_Kphys.temperaturefloatAlbedo[0.2/0.6] Planetary albedo (4)phys.albedofloatG[3/33] Global-mean greenhouse effectKphys.temperaturefloat