PAJOLA, MAURIZIOMAURIZIOPAJOLAHöfner, S.S.HöfnerVincent, J. B.J. B.VincentOklay, N.N.OklayScholten, F.F.ScholtenPreusker, F.F.PreuskerMottola, S.S.MottolaNaletto, G.G.NalettoFornasier, S.S.FornasierLowry, S.S.LowryFeller, C.C.FellerHasselmann, P. H.P. H.HasselmannGüttler, C.C.GüttlerTubiana, C.C.TubianaSierks, H.H.SierksBarbieri, C.C.BarbieriLamy, P.P.LamyRodrigo, R.R.RodrigoKoschny, D.D.KoschnyRickman, H.H.RickmanKeller, H. U.H. U.KellerAgarwal, J.J.AgarwalA'Hearn, M. F.M. F.A'HearnBarucci, M. A.M. A.BarucciBertaux, J. -L.J. -L.BertauxBertini, I.I.BertiniBesse, S.S.BesseBoudreault, S.S.BoudreaultCREMONESE, GabrieleGabrieleCREMONESEda Deppo, V.V.da DeppoDavidsson, B.B.DavidssonDebei, S.S.Debeide Cecco, M.M.de CeccoDeller, J.J.DellerDeshapriya, J. D. P.J. D. P.DeshapriyaEl-Maarry, M. R.M. R.El-MaarryFerrari, S.S.FerrariFerri, F.F.FerriFULLE, MarcoMarcoFULLEGroussin, O.O.GroussinGutierrez, P.P.GutierrezHofmann, M.M.HofmannHviid, S. F.S. F.HviidIp, W. -H.W. -H.IpJorda, L.L.JordaKnollenberg, J.J.KnollenbergKovacs, G.G.KovacsKramm, J. R.J. R.KrammKührt, E.E.KührtKüppers, M.M.KüppersLara, L. M.L. M.LaraLin, Z. -Y.Z. -Y.LinLazzarin, M.M.LazzarinLUCCHETTI, ALICEALICELUCCHETTILopez Moreno, J. J.J. J.Lopez MorenoMarzari, F.F.MarzariMassironi, M.M.MassironiMichalik, H.H.MichalikPenasa, L.L.PenasaPommerol, A.A.PommerolSIMIONI, EMANUELEEMANUELESIMIONIThomas, N.N.ThomasToth, I.I.TothBaratti, E.E.Baratti2020-10-272020-10-2720172397-3366http://hdl.handle.net/20.500.12386/28025Outbursts occur commonly on comets<SUP>1</SUP> with different frequencies and scales<SUP>2,3</SUP>. Despite multiple observations suggesting various triggering processes<SUP>4,5</SUP>, the driving mechanism of such outbursts is still poorly understood. Landslides have been invoked<SUP>6</SUP> to explain some outbursts on comet 103P/Hartley 2, although the process required a pre-existing dust layer on the verge of failure. The Rosetta mission observed several outbursts from its target comet 67P/Churyumov-Gerasimenko, which were attributed to dust generated by the crumbling of materials from collapsing cliffs<SUP>7,8</SUP>. However, none of the aforementioned works included definitive evidence that landslides occur on comets. Amongst the many features observed by Rosetta on the nucleus of the comet, one peculiar fracture, 70 m long and 1 m wide, was identified on images obtained in September 2014 at the edge of a cliff named Aswan<SUP>9</SUP>. On 10 July 2015, the Rosetta Navigation Camera captured a large plume of dust that could be traced back to an area encompassing the Aswan escarpment<SUP>7</SUP>. Five days later, the OSIRIS camera observed a fresh, sharp and bright edge on the Aswan cliff. Here we report the first unambiguous link between an outburst and a cliff collapse on a comet. We establish a new dust-plume formation mechanism that does not necessarily require the breakup of pressurized crust or the presence of supervolatile material, as suggested by previous studies<SUP>7</SUP>. Moreover, the collapse revealed the fresh icy interior of the comet, which is characterized by an albedo >0.4, and provided the opportunity to study how the crumbling wall settled down to form a new talus.STAMPAenArticle10.1038/s41550-017-00922-s2.0-85020021617000406536600004https://www.nature.com/articles/s41550-017-00922017NatAs...1E..92PFIS/05 - ASTRONOMIA E ASTROFISICA