Initial results from the New Horizons exploration of 2014 MU69, a small Kuiper Belt object.
S A SternHarold A WeaverJohn R SpencerCatherine B OlkinG Randall GladstoneWilliam M GrundyJeffrey M MooreDale P CruikshankH A ElliottWilliam B McKinnonJoel Wm ParkerA J VerbiscerLeslie A YoungD A AguilarJ M AlbersT AndertJ P AndrewsF BagenalM E BanksB A BauerJ A BaumanK E BechtoldChloe BeddingfieldN BehroozK B BeisserS D BenecchiE BernardoniRoss A BeyerS BhaskaranCarver J BiersonRichard BinzelE M BirathM K BirdD R BooneA F BowmanVeronica J BrayD T BrittL E BrownM R BuckleyM W BuieBonnie J BurattiL M BurkeS S BushmanB CarcichA L ChaikinC L ChavezAndrew F ChengE J ColwellS J ConardM P ConnerC A ConradJ C CookS B CooperO S CustodioCristina M Dalle OreC C DeboyP DharmavaramR D DhingraG F DunnAlissa M EarleA F EganJ EisigMohamed Ramy El-MaarryC EngelbrechtB L EnkeC J ErcolE D FattigC L FerrellT J FinleyJ FirerJ FischettiWilliam M FolknerM N FosburyG H FountainJ M FreezeL GabasovaL S GlazeJames GreenG A GriffithY GuoM HahnD W HalsD P HamiltonS A HamiltonJ J HanleyA HarchK A HarmonH M HartJ HayesC B HersmanM E HillT A HillJason D HofgartnerM E HoldridgeMihály HorányiA HosadurgaA D HowardCarly J A HowettS E JaskulekD E JenningsJ R JensenM R JonesH K KangD J KatzD E KaufmannJ J KavelaarsJames T KeaneG P KeleherM KinczykM C KochtePeter KollmannS M KrimigisG L KruizingaD Y KusnierkiewiczM S LahrTod R LauerG B LawrenceJ E LeeE J Lessac-ChenenI R LinscottC M LisseA W LunsfordD M MagesV A MallderN P MartinB H MayDavid J McComasRalph L McNuttD S MehokeThomas MehokeDerek S NelsonH D NguyenJorge I NúñezA C OcampoW M OwenG K OxtonA H ParkerM PätzoldJohn Y PelgriftF J PelletierJ P PineauM R PiquetteS B PorterSilvia ProtopapaEric QuiricoJ A RedfernA L RegiecH J ReitsemaD C ReuterDerek C RichardsonJ E RiedelM A RitterbushStuart J RobbinsD J RodgersG D RogersD M RoseP E RosendallKirby RunyonM G RyschkewitschM M SainaM J SalinasPaul M SchenkJ R ScherrerW R SchleiBernard SchmittD J SchultzD C SchurrFrancesca ScipioniR L SepanR G SheltonMark R ShowalterM SimonKelsi N SingerE W StahlheberD R StanbridgeJ A StansberryA J StefflD F StrobelM M StothoffT StrykJ R StuartM E SummersM B TapleyA TaylorH W TaylorR M TedfordH B ThroopL S TurnerO M UmurhanJ Van EckD VelezM H VersteegM A VincentR W WebbertS E WeidnerG E WeigleJ R WendelO L WhiteK E WhittenburgB G WilliamsK E WilliamsS P WilliamsH L WintersA M ZangariT H ZurbuchenPublished in: Science (New York, N.Y.) (2019)
The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU69, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU69 is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU69's origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.