J/AJ/169/30ivo://CDS.VizieR/J/AJ/169/30doi:10.26093/cds/vizier/be-59-yCDSBalmer W.O.Franson K.Chomez A.Pueyo L.Stolker T.Lacour S.,Nowak M.Nasedkin E.Bonse M.J.Thorngren D.Palma-Bifani P.,Molliere P.Wang J.J.Zhang Z.Chavez A.Kammerer J.Blunt S.,Bowler B.P.Bonnefoy M.Brandner W.Charnay B.Chauvin G.Henning T.,Lagrange A.-M.Pourre N.Rickman E.De Rosa R.Vigan A.,Winterhalder T.2026-07-02T11:52:09Z2025-11-07T14:46:15ZCDS support team

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

cds-question@unistra.frinterferometryexoplanetsinfrared-astronomyspectroscopyDirect imaging observations are biased toward wide-separation, massive companions that have degenerate formation histories. Although the majority of exoplanets are expected to form via core accretion, most directly imaged exoplanets have not been convincingly demonstrated to follow this formation pathway. We obtained new interferometric observations of the directly imaged giant planet AF Lep b with the VLTI/GRAVITY instrument. We present three epochs of ~50uas relative astrometry and the K-band spectrum of the planet for the first time at a resolution of R=500. Using only these measurements, spanning less than 2 months, and the Hipparcos-Gaia Catalogue of Accelerations, we are able to significantly constrain the planet's orbit; this bodes well for interferometric observations of planets discovered by Gaia DR4. Including all available measurements of the planet, we infer an effectively circular orbit (e<0.02, 0.07, and 0.13 at 1{sigma}, 2{sigma}, and 3{sigma}, respectively) in spin-orbit alignment with the host and measure a dynamical mass of Mp=3.75+/-0.5MJup. Models of the spectrum of the planet show that it is metal-rich ([M/H]=0.75+/-0.25), with a C/O abundance encompassing the solar value. This ensemble of results shows that the planet is consistent with core accretion formation.2025AJ....169...30Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/169/30CatalogResearchIsServedByTAP VizieR generic servicerelated-toI/259 : The Tycho-2 Catalogue (Hog+ 2000)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)I/357 : Gaia DR3 Part 3. Non-single stars (Gaia Collaboration, 2022)J/A+A/415/1153 : [Fe/H] for 98 extra-solar planet-host stars (Santos+, 2004)J/ApJ/622/1102 : The planet-metallicity correlation. (Fischer+, 2005)J/A+A/523/A58 : PDF Atlas and spectra of FeH molecule in LHS 2 (Wende+, 2010)J/MNRAS/434/1469 : ExoMol line lists for SiO (Barton+, 2013)J/ApJ/777/160 : NIR imaging survey for planets around MG stars (Biller+, 2013)J/MNRAS/437/1828 : ExoMol line list for HCN and HNC (Barber+, 2014)J/MNRAS/442/1821 : ExoMol line list for KCl (Barton+, 2014)J/A+A/564/A125 : AGN Torus model comparison of AGN in the CDFS (Buchner+, 2014)J/MNRAS/454/593 : Young moving groups in solar neighbourhood (Bell+, 2015)J/MNRAS/446/2337 : ExoMol line lists for phosphine (PH_3_) (Sousa-Silva+, 2015)J/A+A/589/A21 : K-H2 line shapes for cool brown dwarfs spectra (Allard+, 2016)J/MNRAS/460/4063 : ExoMol line list for H2S AYT2 (Yurchenko+, 2016)J/ApJS/225/10 : Kinematic analysis of M7-L8 dwarfs (Faherty+, 2016)J/ApJ/833/96 : Hawaii IR parallax program. II. Ultracool dwarfs (Liu+, 2016)J/MNRAS/463/771 : ExoMol XVIII. VO high-temperature spectrum (McKemmish+, 2016)J/ApJ/831/64 : Mass-metallicity relation for giant planets (Thorngren+, 2016)J/AJ/153/208 : LCES HIRES/Keck radial velocity Exoplanet Survey (Butler+, 2017)J/A+A/603/A30 : Evidence for 2 distinct giant planet population (Santos+, 2017)J/A+A/605/A95 : CH4 and hot CH3OH continuum hybrid line list (Yurchenko+, 2017)J/AJ/156/286 : The LEECH exoplanet imaging survey (Stone+, 2018)J/MNRAS/490/4638 : ExoMol molecular line lists. XXXV. NH3 (Coles+, 2019)J/A+A/623/A72 : Binarity of Hipparcos stars: Gaia pm anomaly (Kervella+, 2019)J/MNRAS/488/2836 : ExoMol Molecular linelists. XXXIII. TiO (McKemmish+, 2019)J/AJ/158/13 : The first 300 stars observed by the GPIES (Nielsen+, 2019)J/ApJ/874/L31 : Giant planet bulk & atmosphere metallicities (Thorngren+, 2019)J/AJ/159/63 : New AO obs. of exoplanets & brown dwarf companions (Bowler+,2020)J/A+A/633/A110 : K band spectrum of beta Pictoris b (GRAVITY+, 2020)J/ApJ/903/55 : APOGEE parameters through 83 open clusters (Poovelil+, 2020)J/AJ/160/207 : OSIRIS K-band spectr. of {kappa} Andromedae b (Wilcomb+, 2020)J/ApJS/254/42 : Hipparcos-Gaia (EDR3) Catalog of Accelerations (Brandt, 2021)J/ApJ/940/164 : An updated distance-calibrated SED of Gl 229B (Calamari+, 2022)J/A+A/657/A7 : Stellar & substellar companions from Gaia EDR3 (Kervella+, 2022)J/A+A/659/A135 : 178 debris systems (Pearce+, 2022)J/AJ/163/159 : Species abundances in WASP-77A (Reggiani+, 2022)J/AJ/165/164 : Tull RVels, rotation periods and Inclinations (Bowler+, 2023)J/A+A/675/A205 : SPHERE high-contrast data with PACO (Chomez+, 2023)J/AJ/165/39 : CHARIS and SPHERE/IFS IR spectra of HIP 21152 (Franson+, 2023)J/AJ/166/85 : K-band spectroscopy of HD 284149b (Hoch+, 2023)J/ApJ/953/170 : FIRE MRS spectrum of BD UGPSJ072227.51-054031.2 (Hood+, 2023)J/A+A/672/A93 : AF Lep b spectrum (Mesa+, 2023)J/AJ/167/64 : HD 136164 Ab IR spectrum with VLTI/GRAVITY (Balmer+, 2024)J/A+A/684/A69 : beta Pic Moving Group photometry (Gratton+, 2024)J/AJ/167/45 : Abundances in HD 181327 with MIKE (Reggiani+, 2024)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/169/30https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/169/30http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/169/30https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/169/30https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/169/30http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/169/30GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfrareddefaultJ/AJ/169/30/fig2aSPHERE spectrum of AF Lep b (Data behing Figure 2)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLambdaWavelengthumem.wlfloatFlux1D flux1000W.m**-2.nm**-1phot.mag;em.IR.KdoubleContrast1D contrastphot.flux;arith.ratio;em.IR.KdoubleJ/AJ/169/30/fig2bGRAVITY spectrum of AF Lep b (Data behind Figure 2)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLambdaWavelengthumem.wlfloatFlux1D flux1000W.m**-2.nm**-1phot.mag;em.IR.KdoubleContrast1D contrastphot.flux;arith.ratio;em.IR.Kdouble