J/AJ/157/228ivo://CDS.VizieR/J/AJ/157/228doi:10.26093/cds/vizier.51570228CDSThirouin A.Sheppard S.S.2019-08-28T11:45:39Z2019-08-19T14:32:02ZCDS support team

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

cds-question@unistra.frsolar-systemasteroidsphotometryvisible-astronomyinfrared-photometryWe present a survey of the rotational and physical properties of the dynamically low inclination Cold Classical (CC) trans-Neptunian objects (TNOs). The CCs are primordial planetesimals and contain information about our solar system and planet formation over the first 100 million years after the Sun's formation. We obtained partial/complete light curves for 42 CCs. We use statistical tests to derive general properties about the shape and rotational frequency distributions of the CCs and infer that they have slower rotations and are more elongated/deformed than the other TNOs. On the basis of the full light curves, the mean rotational period of the CCs is 9.48+/-1.53 hr compared to 8.45+/-0.58 hr for the rest of the TNOs. About 65% of the TNOs have a light-curve amplitude below 0.2 mag compared to the 36% of CCs with small amplitude. We present the full light curve of one likely contact binary, 2004 VC_131_, with a potential density of 1 g/cm^3^ for a mass ratio of 0.4. We have hints that 2004 MU_8_ and 2004 VU_75_ are perhaps potential contact binaries, on the basis of their sparse light curves, but more data are needed to confirm this finding. Assuming equal-sized binaries, we find that ~10%-25% of the CCs could be contact binaries, suggesting a deficit of contact binaries in this population compared to previous estimates and to the (~40%-50%) possible contact binaries in the Plutino population. These estimates are lower limits and may increase if nonequal-sized contact binaries are considered. Finally, we put in context the results of the New Horizons flyby of 2014 MU_69_.2019AJ....157..228Thttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/157/228CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/522/A93 : Short-term variability of 29 minor planets (Thirouin+, 2010)J/A+A/569/A3 : Rotational properties of TNOs (Thirouin+, 2014)J/AJ/154/62 : Orbital parameters of Kuiper Belt objects (Volk+, 2017)J/AJ/154/241 : Photometry of a Kuiper Belt object: 2002 CC_249_http://minorplanetcenter.net/ : MPC databasehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/157/228https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/157/228http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/157/228https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/157/228https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/157/228http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/157/228GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/AJ/157/228/table2Periodicity and amplitude findingsD0.20[108/297]? Diameter, assuming albedo of 0.20kmphys.size.diameterintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTNOTrans-Neptunian object (TNO) namemeta.id;meta.maincharprimarymoreindicates data in Tables 1 and 3 for this TNOmeta.ref.urlcharm_TNO[AB] Multiplicity index on TNOmeta.code.multipcharFlag[1]? Rotation period flag (1)meta.code.errorintnullablel_Per[>] Limit flag on Permeta.code.errorcharPer[1.1/15.7]? Periodicityhtime.periodfloatnullablel_Dmag[>] Limit flag on dmagmeta.code.error;arith.diffcharDmag[0.08/0.55] Full lightcurve amplitude {Delta}mmagsrc.var.amplitudefloate_Dmag[0.04]? Uncertainty in Dmagmagstat.error;phot.mag;arith.difffloatnullableu_Dmag[:] Uncertainty flag on Dmag (:=approximate value)meta.code.error;arith.diffcharphi0[7230.85274/8342.83471]? Zero phase without light-time correction (JD-2450000) {phi}_0_dtime.epochdoublenullableHMag[5.0/7.2]? MPC H absolute magnitudemagphys.magAbs;em.IR.HfloatnullableD0.04[241/665]? Diameter, assuming albedo of 0.04kmphys.size.diameterintnullableResResolved binary status (2)meta.notecharLCLight curvemeta.ref.urlcharJ/AJ/157/228/table1Orbital parameters and observing circumstances of Cold Classicals (CCs) observed for this workFilt[VR r'] Filter usedinstr.setup;instr.filtercharTNOTNO namemeta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordinta[42.098/48.029] Minor Planet Center (MPC) semi-major axisAUphys.sizefloate[0.022/0.191] MPC eccentricitysrc.orbital.eccentricityfloati[0.2/9.7] MPC inclinationdegsrc.orbital.inclinationfloatDateUT observation datetime.epoch;obsnullableNobs[1/27] Number of observationsmeta.numberintDelta[37.438/47.259] Geocentric distance, {Delta}AUpos.distance;pos.geocentricfloatrh[38.275/47.638] Heliocentric distanceAUpos.distance;pos.heliocentricfloatalpha[0/1.3] Phase angle, {alpha}degpos.phaseAngfloatTelTelescope used (Magellan or DCT)instr.setupcharJ/AJ/157/228/table3Photometry used in this paperrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTNOTNO namemeta.id;meta.maincharm_TNO[AB] Multiplicity index on TNOmeta.code.multipcharJDJulian Date of observation without light-time correctiondtime.epochdoubleomag[-0.54/0.44] Relative observed magnitudemagphot.mag;arith.difffloate_omag[0.02/0.18] Uncertainty in omagmagstat.error;phot.magfloat