Researchers. Mario Di Mar(no INAF Osservatorio Astrofisico di Torino

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1 Contribu?onoftheTorinoTeamtoSSAac?vi?es MarioDiMar(no INAF OsservatorioAstrofisicodiTorino TheTorinoTeamincludesthePlanetaryScience TeamatINAF OATo,andresearchersfromthe TorinoUniversityandfromtheINAF OAA. Theac?vitesaremainlyfocusedonthe determina?onofthephysicalproper?esofneo, andonimpactcratersearchandstudy. Researchers A.Cellino INAF OATo PrimoRicercatore M.DiMar?no INAF OATo Ricercatore A.Cora INAF OATo CollaboratoreTecnico A.Dell Oro INAF OAA Ricercatore M.Bertaina Univ.Torino Ricercatore

2 FieldofinterestinSSA:NEO Studiesofthetheroleofcollisionsintheevolu?onoftheasteroid popula?onandintheoriginofneos. Deriva?onofNEAphysicalparametersbymeansof polarimetricobserva?ons. Impactcratering:Searchandinsituanalysisofnewimpact craters;publica?onofacatalogueoftheknownimpactcraters; developmentofanautoma?ctooltoiden?fypossibleimpact cratersonearthsurfaceinsatelliteimagery(cosmo SkyMedetal.). DevelopmentofsuitablealgorithmstoprocessfutureGaiaspace missiondata,inordertoderivethephysicalproper?esofmainbelt asteroidsandneas. Numericalsimula?onsoftheperformancesoftheproposed JEM Eusospacemissionfordetec?onandanalysisofmeteorand fireballevents. Detec?onofmeteorphenomenafromspace basedplatorms.

3 Previousexperienceandobtainedresults Fundamentalcontribu?onsinthefieldofcollisional processes,inpar?culartheiden?fica?onofasteroid dynamicalfamilies. Amongthemaximumworldexpertsofasteroid Polarimetry,andderiva?onofNEAalbedoesand sizesfrompolarimetricdata.developmentof instrumentssuitableforasteroidpolarimetry. Iden?fica?onandinsituanalysisofimpactcraterson Earth ssurface. Responsibilityonthederiva?onofphysicalproper?es ofsolarsystemobjectsfromfuturegaiadata. FirstItalianexperienceonasteroidradarobserva?ons incollabora?onwithinaf IRA,JPLandIRA Kharkiv. DevelopmentforESAoftheSPOSHcamera.

4 Families as possible sources of NEO and meteorite showers Sooner (immediate injection into resonance) or later (Yarkovsky) collisional fragments reach the region of the terrestrial planets!

5 EXAMPLE: POLARIMETRIC OBSERVATIONS OF (25143) ITOKAWA AT LARGE PHASE ANGLES in 2004 at CASLEO Fromtheobtainedpolarimetricslope,the geometricalbedoofitokawaturnsoutto be: p v =0.24±0.03whichagreeswithin 7%withtheHayabusaresults. The determination of the albedo of the (99942) Apophis Observa(onsperformedattheESOVLTtelescope. (Delbòetal.,2007) Results:p v =0.33±0.08 ThesizeofApophisturnsouttobe:D=270±30m

6 Discoveryandinsituanalysisofimpactcratersonthe Earthsurface Kamilcrater

7 SPOSH SmartPanoramicOp?calSensorHead

8 ToolsadoptedintheTeaminves?ga?ons Developmentofsuitablenumericalcodesandalgorithms(HCM)forfamily iden?fica?on. DevelopmentofJavaalgorithmstobeimplementedinthedata reduc?on pipelineofgaiamission. DevelopmentofanumericalsimulatorofmeteoreventsobservedfromISS. UBVRIPhotopolarimeterdesignedandbuiltinTorino,andsubsequently afachedatthe2.2 mtelescopeofcasleo(argen?na). ESOVLTandLiverpool(LaPalma)telescopes. Directinsituexplora?onofimpactcraters,orsupposedtobeimpact structures. RadarinEvpatoria(Crimea)andthe Medicina32 mradiotelescope. The2.2 mtelescopeatcomplejoastronomico ElLeoncito(SanJuan,Argen?na)

9 Current developments and improvements The development of a new polarimeter, by using state of the art technology. The instrument is under construc?on at INAF OATo. To be installed at the Calern astronomical sta?on of the Observatoire de la Côte d Azur (France) in the framework of an interna?onal collabora?on. Cost: 22,000 funded by INAF

10 Studiesofthetheroleof collisionsintheevolu?onof theasteroidpopula?on Physics of collisional disruption phenomena Asteroid Collisional Evolution Acollabora?onbetweenINAF OATo,Pisa Univ.andBelgradeObservatory.Goal:tobuild andmaintainapublicdata baseoffamilies andcorrespondingmemberships,tobeused forfindinglinkswithknownneoand meteorites. Asteroid inventory and size distribution Asteroid Dynamical Evolution Asteroid Families Formation of Binary Systems Asteroid interiors Meteorite showers Origin of near-earth Asteroids

11 NEA Polarimetry C type S type E type Presenceofawidebranchof posi(vepolariza(onwitha maximumnear90. NEOpolarimetryisinherently efficient,becauseneoscanbe observedathighphaseangles. Therateofvaria?onofthe phaseangleisfastforthese objects,thusapolarimetric slopecanbeobtainedinashort?me. Interes?ngforthepurposesof ESASSA Even a single measurement of polarization at phase > 40 deg can be sufficient to obtain an overall albedo estimation!verysmall(faint) NEAsareobservablewiththeVLT(asshownbythecaseofApophis).

12 X COSM Project (Impact Crater Survey by COSMO SkyMed) OATo ASI Univ. Chie1 1) Compila?on of a catalogue of the exis?ng impact craters on Earth (about 180) by using COSMO SkyMed and other satellites images. 2) Analysis of satellite imagery at various wavelengths, from visible to radar, by using custom designed pafern recogni?on algorithms, especially developed for this purpose.

13 The GAIA inversion problem: The objects are assumed to be triaxial ellipsoids. A genetic algorithm is used to solve for the unknown spin period, spin axis direction, two axial ratios, and a phase-magnitude linear coefficient. GAIA photometricdata The results are generally encouraging: More than 100,000 asteroids should be potentially invertible, including NEOs

14 Need of extending the near-earth object inventory and size distribution to smaller sizes.this is the domain of meteoroids Wai?ngforSPOSH likesensorsinorbit NewtypeofobservatoryonboardoftheISS,to observetransientluminousphenomenainthe Earth satmosphere. WorkingatUVwavelengths. Widefield(60 ),largeaperture(2.5m)telescope. JEM EUSOprimaryobjec(ve:ExtremeEnerge(c CosmicRays(EECR) ev through observa(onoffluorescenceandcherenkov photonsgeneratedbyairshowers. Applications to meteor and atmosphere transient phenomena. Ongoing studies with responsibility at INAF-OATO and UniTo.