J/A+A/631/A149ivo://CDS.VizieR/J/A+A/631/A149doi:10.26093/cds/vizier.36310149CDSRozek A.Lowry S.C.Nolan M.C.Taylor P.A.Benner L.A.M.,Fitzsimmons A.Zegmott T.J.Weissman P.R.Green S.F.Rozitis B.,Snodgrass C.Smythe W.D.Hicks M.D.Howell E.S.Virkki A.K.,Aponte-Hernandez B.Rivera-Valentin E.G.Rodriguez-Ford L.A.,Zambrano-Marin L.F.Brozovic M.Naidu S.P.Giorgini J.D.Snedeker L.G.,Jao J.S.Ghigo F.D.2019-11-13T05:44:17Z2019-11-13T06:36:52ZCDS support team

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

cds-question@unistra.frasteroidsphotometryThe potentially hazardous asteroid (85990) 1999 JV6 has been a target of previously published thermal-infrared observations, and optical photometry. It has been identified as a promising candidate for possible Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect detection. The YORP effect is a small thermal-radiation torque attributed to be a key factor in spin-state evolution of small Solar System bodies. In order to detect YORP on 1999 JV6 we develop a detailed shape model and analyse the spin-state using both optical and radar observations. For 1999 JV6, we collected optical photometry between 2007 and 2016. Additionally, we obtained radar echo-power spectra and imaging observations with Arecibo and Goldstone planetary radar facilities in 2015, 2016, and 2017. We combine our data with published optical photometry to develop a robust physical model. We determine that the rotation pole resides at negative latitudes in an area with a 5{deg} radius, close to the south ecliptic pole. The refined sidereal rotation period is 6.536787+/-0.000007h. The radar images are best reproduced with a bilobed shape model. Both lobes of 1999 JV6 can be represented as oblate ellipsoids with a smaller, more spherical component resting at the end of a larger, more elongated component. While contact binaries appear to be abundant in the near-Earth population, there exists just a few published shape models for asteroids in this particular configuration. By combining the radar-derived shape model with optical light curves we determine a constant-period solution that fits all available data well. Using light curve data alone we determine an upper limit for YORP 8.5x10^-8^rad/day^2^. The bifurcated shape of 1999 JV6 might be a result of two ellipsoidal components gently merging with each other, or a deformation of a rubble pile with a weak-tensile-strength core due to spin-up. The physical model of 1999 JV6 presented here will enable future studies of contact binary asteroid formation and evolution.2019A&A...631A.149Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/631/A149CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/631/A149https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/631/A149http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/631/A149https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/631/A149https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/631/A149http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/631/A149GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/631/A149/listList of light curvesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLCNo[1/28] Light curve number (G1)meta.idintNptNumber of datapointsmeta.numberintFilter[RrVc] Filtermeta.id;instr.filtercharLCShow the light curvemeta.ref.urlcharJ/A+A/631/A149/tablea2Measured optical light curves of (85990) 1999 JV6 used in the shape and spin-state analysis, including published photometryJDJulian Datedtime.epochdoubleFilter[RrVc] Filtermeta.id;instr.filtercharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLCNoLight curve number (G1)meta.idintmagRelative Magnitudemagphot.mag;arith.difffloate_mag1-sigma uncertainty in relative magnitudemagstat.error;phot.magfloat