J/AJ/170/49ivo://CDS.VizieR/J/AJ/170/49doi:10.26093/cds/vizier/be-5a-1hCDSLuque R.Coy B.P.Xue Q.Feinstein A.D.Ahrer E.-M.Changeat Q.,Zhang M.Moran S.E.Bean J.L.Kite E.Mansfield M.W.Palle E.2026-08-03T07:20:14Z2026-04-29T13:26:40ZCDS support team

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

cds-question@unistra.frexoplanetsinfrared-astronomyspectroscopyWe report JWST NIRSpec/G395H observations of TOI-1685 b, a hot rocky super-Earth orbiting an M2.5V star, during a full orbit. We obtain transmission and emission spectra of the planet and characterize the properties of the phase curve, including its amplitude and offset. The transmission spectrum rules out clear H2-dominated atmospheres, while secondary atmospheres (made of water, methane, sulfur dioxide, or carbon dioxide) cannot be statistically distinguished from a flat line. The emission spectrum is featureless and consistent with a dark surface, ruling out carbon dioxide-, sulfur dioxide-, or methane-dominated atmospheres thicker than 100 mbar. Collecting all evidence, the properties of TOI-1685 b are consistent with a blackbody with no heat redistribution and a low albedo, with a dayside brightness temperature 0.99+/-0.07 times that of a perfect blackbody in the NIRSpec NRS2 wavelength range (3.823-5.172um). Our results add to the growing number of seemingly airless M-star rocky planets, thus constraining the location of the "Cosmic Shoreline." Three independent data reductions have been carried out, all showing a high-amplitude correlated noise component in the white and spectroscopic light curves. The correlated noise properties are different between the NRS1 and NRS2 detectors-importantly, the timescales of the strongest components (4.5 hr and 2.5 hr, respectively)-suggesting the noise is from instrumental rather than astrophysical origins. We encourage the community to look into the systematics of NIRSpec for long time series observations.2025AJ....170...49Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/170/49CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/MNRAS/459/3890 : ExoMol line lists for SO2 (Underwood+, 2016)J/MNRAS/468/3907 : HAT-P-18b wavelength binned light curves (Kirk+, 2017)J/A+A/605/A95 : CH4 & hot methane continuum hybrid line list (Yurchenko+, 2017)J/other/Sci/377.1211 : RV and LC of 8 M dwarf stars with planets (Luque+, 2022)J/A+A/698/A68 : Hot Rocks Survey II. TOI-1468 b fluxes (Meier Valdes+, 2025)J/AJ/169/38 : HD 189733b NIRCam transmission & emission spectra (Zhang+, 2025)J/A+A/696/A28 : TOI-238 and TOI-1685 light curves (Egger+, 2025)http://doi.org/10.17909/jhgr-hc58 : MAST datahttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/170/49https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/170/49http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/170/49https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/170/49https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/170/49http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/170/49GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfrareddefaultJ/AJ/170/49/table7NIRSpec/G395H NRS1 Transmission SpectrumrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintwave[2.8/3.7] Wavelengthumem.wlfloate_wave[0.01/0.02] Uncertainty in waveumstat.error;em.wlfloatDepth-Eu[703.9/864.7] Transit depth, Eureka!(10-6)src.var.amplitudefloate_Depth-Eu[38/45.9] Lower uncertainty in Eureka(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Eu[36.7/45.1] Upper uncertainty in Eureka(10-6)stat.error;stat.max;src.var.amplitudefloatDepth-Ti[702.5/889.7] Transit depth, Tiberius(10-6)src.var.amplitudefloate_Depth-Ti[41.7/50.8] Lower uncertainty in Tiberius(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Ti[41.3/51.7] Upper uncertainty in Tiberius(10-6)stat.error;stat.max;src.var.amplitudefloatDepth-Ex[718.3/898.9] Transit depth, ExoTIC-JEDI(10-6)src.var.amplitudefloate_Depth-Ex[32.7/64.7] Lower uncertainty in ExoTIC-JEDI(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Ex[31/60.2] Upper uncertainty in ExoTIC-JEDI(10-6)stat.error;stat.max;src.var.amplitudefloatJ/AJ/170/49/table8NIRSpec/G395H NRS2 Transmission SpectrumrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintwave[3.8/5.2] Wavelengthumem.wlfloate_wave[0.01/0.02] Uncertainty in waveumstat.error;em.wlfloatDepth-Eu[597.2/916.5] Transit depth, Eureka!(10-6)src.var.amplitudefloate_Depth-Eu[44.4/102] Lower uncertainty in Eureka(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Eu[43.9/100] Upper uncertainty in Eureka(10-6)stat.error;stat.max;src.var.amplitudefloatDepth-Ti[430.1/959.7] Transit depth, Tiberius(10-6)src.var.amplitudefloate_Depth-Ti[52.2/125] Lower uncertainty in Tiberius(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Ti[52.3/127] Upper uncertainty in Tiberius(10-6)stat.error;stat.max;src.var.amplitudefloatDepth-Ex[535.7/1008] Transit depth, ExoTIC-JEDI(10-6)src.var.amplitudefloate_Depth-Ex[50.5/229] Lower uncertainty in ExoTIC-JEDI(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Ex[46.8/195] Upper uncertainty in ExoTIC-JEDI(10-6)stat.error;stat.max;src.var.amplitudefloatJ/AJ/170/49/table9NIRSpec/G395H Emission SpectrumE_Depth-Eu-1[17.4/29.5] Upper uncertainty in Eureka-1(10-6)stat.error;stat.max;src.var.amplitudefloatDepth-Eu-2[63.9/148] Eclipse depth, Eureka!, Second eclipse(10-6)src.var.amplitudefloate_Depth-Eu-2[19.2/31.1] Lower uncertainty in Eureka-2(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Eu-2[20.8/30.9] Upper uncertainty in Eureka-2(10-6)stat.error;stat.max;src.var.amplitudefloatDepth-Eu-C[58.7/138.2] Eclipse depth, Eureka!, Combined(10-6)src.var.amplitudefloate_Depth-Eu-C[13.6/24.3] Lower uncertainty in Eureka-C(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Eu-C[13.5/23.8] Upper uncertainty in Eureka-C(10-6)stat.error;stat.max;src.var.amplitudefloatDepth-Eu-F[91.5/178.3] Eclipse depth, Eureka!, Full phase curve(10-6)src.var.amplitudefloate_Depth-Eu-F[9.5/18.5] Lower uncertainty in Eureka-F(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Eu-F[9.6/19.1] Upper uncertainty in Eureka-F(10-6)stat.error;stat.max;src.var.amplitudefloatDepth-Ti-C[54.7/137.6] Eclipse depth, Tiberius, Combined(10-6)src.var.amplitudefloate_Depth-Ti-C[15/29.2] Lower uncertainty in Tiberius-C(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Ti-C[14.9/29] Upper uncertainty in Tiberius-C(10-6)stat.error;stat.max;src.var.amplitudefloatDepth-Ti-F[93.5/183.1] Eclipse depth, Tiberius, Full phase curve(10-6)src.var.amplitudefloate_Depth-Ti-F[10/24.6] Lower uncertainty in Tiberius-F(10-6)stat.error;stat.min;src.var.amplitudefloatE_Depth-Ti-F[10.1/24.9] Upper uncertainty in Tiberius-F(10-6)stat.error;stat.max;src.var.amplitudefloate_Depth-Ex-1[18.6/27.7] Uncertainty in ExoTIC-JEDI-1(10-6)stat.error;src.var.amplitudefloatDepth-Ex-2[43.5/152.2] Eclipse depth, ExoTIC-JEDI, Second eclipse(10-6)src.var.amplitudefloate_Depth-Ex-2[13.9/33.5] Uncertainty in ExoTIC-JEDI-2(10-6)stat.error;src.var.amplitudefloatDepth-Ex-C[73.1/118.7] Eclipse depth, ExoTIC-JEDI, Combined(10-6)src.var.amplitudefloate_Depth-Ex-C[16.9/26.5] Uncertainty in ExoTIC-JEDI-C(10-6)stat.error;src.var.amplitudefloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintwave[2.9/5.02] Wavelengthumem.wlfloate_wave[0.08/0.14] Uncertainty in waveumstat.error;em.wlfloatDepth-Eu-1[59.8/139.1] Eclipse depth, Eureka!, First eclipse(10-6)src.var.amplitudefloate_Depth-Eu-1[17.7/28.3] Lower uncertainty in Eureka-1(10-6)stat.error;stat.min;src.var.amplitudefloatDepth-Ex-1[77.9/124.4] Eclipse depth, ExoTIC-JEDI, First eclipse(10-6)src.var.amplitudefloat