Nightside condensation of iron in an ultrahot giant exoplanet

Ehrenreich, DavidDavidEhrenreichLovis, ChristopheChristopheLovisAllart, RomainRomainAllartZapatero Osorio, María RosaMaría RosaZapatero OsorioPepe, FrancescoFrancescoPepeCRISTIANI, StefanoStefanoCRISTIANIRebolo, RafaelRafaelReboloSantos, Nuno C.Nuno C.SantosBORSA, FrancescoFrancescoBORSADemangeon, OlivierOlivierDemangeonDumusque, XavierXavierDumusqueGonzález Hernández, Jonay I.Jonay I.González HernándezCasasayas-Barris, NúriaNúriaCasasayas-BarrisSégransan, DamienDamienSégransanSousa, SérgioSérgioSousaAbreu, ManuelManuelAbreuAdibekyan, VardanVardanAdibekyanAffolter, MichaelMichaelAffolterAllende Prieto, CarlosCarlosAllende PrietoAlibert, YannYannAlibertAliverti, MatteoMatteoAlivertiAlves, DavidDavidAlvesAmate, ManuelManuelAmateAvila, GerardoGerardoAvilaBALDINI, VeronicaVeronicaBALDINIBandy, TimothyTimothyBandyBenz, WillyWillyBenzBIANCO, ANDREAANDREABIANCOBolmont, ÉmelineÉmelineBolmontBouchy, FrançoisFrançoisBouchyBourrier, VincentVincentBourrierBroeg, ChristopherChristopherBroegCabral, AlexandreAlexandreCabralCALDERONE, GIORGIOGIORGIOCALDERONEPallé, EnricEnricPalléCegla, H. M.H. M.CeglaCIRAMI, ROBERTOROBERTOCIRAMICoelho, João M. P.João M. P.CoelhoConconi, PaoloPaoloConconiCORETTI, IgorIgorCORETTICumani, ClaudioClaudioCumaniCUPANI, GuidoGuidoCUPANIDekker, HansHansDekkerDELABRE, BERNARD ALEXISBERNARD ALEXISDELABREDeiries, SebastianSebastianDeiriesD'ODORICO, ValentinaValentinaD'ODORICODI MARCANTONIO, PaoloPaoloDI MARCANTONIOFigueira, PedroPedroFigueiraFragoso, AnaAnaFragosoGenolet, LudovicLudovicGenoletGenoni, MatteoMatteoGenoniGénova Santos, RicardoRicardoGénova SantosHara, NathanNathanHaraHughes, IanIanHughesIwert, OlafOlafIwertKerber, FlorianFlorianKerberKnudstrup, JensJensKnudstrupLANDONI, MarcoMarcoLANDONILavie, BaptisteBaptisteLavieLizon, Jean-LouisJean-LouisLizonLendl, MonikaMonikaLendlLo Curto, GaspareGaspareLo CurtoMaire, CharlesCharlesMaireManescau, AntonioAntonioManescauMartins, C. J. A. P.C. J. A. P.MartinsMégevand, DenisDenisMégevandMehner, AndreaAndreaMehnerMICELA, GiuseppinaGiuseppinaMICELAModigliani, AndreaAndreaModiglianiMOLARO, PaoloPaoloMOLAROMonteiro, ManuelManuelMonteiroMonteiro, MarioMarioMonteiroMoschetti, ManueleManueleMoschettiMüller, EricEricMüllerNunes, NelsonNelsonNunesOGGIONI, LUCALUCAOGGIONIOliveira, AntónioAntónioOliveiraPARIANI, GiorgioGiorgioPARIANIPasquini, LucaLucaPasquiniPORETTI, EnnioEnnioPORETTIRasilla, José LuisJosé LuisRasillaREDAELLI, EDOARDO MARIA ALBERTOEDOARDO MARIA ALBERTOREDAELLIRIVA, MarcoMarcoRIVASantana Tschudi, SamuelSamuelSantana TschudiSantin, PaoloPaoloSantinSantos, PedroPedroSantosSegovia Milla, AlexAlexSegovia MillaSeidel, Julia V.Julia V.SeidelSosnowska, DanutaDanutaSosnowskaSOZZETTI, AlessandroAlessandroSOZZETTISpanò, PaoloPaoloSpanòSuárez Mascareño, AlejandroAlejandroSuárez MascareñoTabernero, HugoHugoTaberneroTenegi, FabioFabioTenegiUdry, StéphaneStéphaneUdryZANUTTA, AlessioAlessioZANUTTAZERBI, Filippo MariaFilippo MariaZERBI2022-02-182022-02-1820200028-0836http://hdl.handle.net/20.500.12386/31421Ultrahot giant exoplanets receive thousands of times Earth's insolation1,2. Their high-temperature atmospheres (greater than 2,000 kelvin) are ideal laboratories for studying extreme planetary climates and chemistry3-5. Daysides are predicted to be cloud-free, dominated by atomic species6 and much hotter than nightsides5,7,8. Atoms are expected to recombine into molecules over the nightside9, resulting in different day and night chemistries. Although metallic elements and a large temperature contrast have been observed10-14, no chemical gradient has been measured across the surface of such an exoplanet. Different atmospheric chemistry between the day-to-night (`evening') and night-to-day (`morning') terminators could, however, be revealed as an asymmetric absorption signature during transit4,7,15. Here we report the detection of an asymmetric atmospheric signature in the ultrahot exoplanet WASP-76b. We spectrally and temporally resolve this signature using a combination of high-dispersion spectroscopy with a large photon-collecting area. The absorption signal, attributed to neutral iron, is blueshifted by -11 ± 0.7 kilometres per second on the trailing limb, which can be explained by a combination of planetary rotation and wind blowing from the hot dayside16. In contrast, no signal arises from the nightside close to the morning terminator, showing that atomic iron is not absorbing starlight there. We conclude that iron must therefore condense during its journey across the nightside.STAMPAenNightside condensation of iron in an ultrahot giant exoplanetArticle10.1038/s41586-020-2107-12-s2.0-85083779045WOS:000526613500001https://www.nature.com/articles/s41586-020-2107-1https://api.elsevier.com/content/abstract/scopus_id/850837790452020Natur.580..597EFIS/05 - ASTRONOMIA E ASTROFISICAERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation::PE9_2 Planetary systems sciences