The NEOShield-2 (2015-2017) project has been recently approved by the European Commission in the framework of the Horizon 2020 programme with the aim i) to study specific technologies and instruments to conduct close approach missions to NEOs or to undertake mitigation demonstration, and ii) to acquire in-depth information of physical properties of the population of small NEOs (50-300 m), in order to design mitigation missions and assess the consequences of an impact on Earth. The Italian scientific community is widely involved in this project

Bertini I.

Cortese M.

Di Paola A.

Dotto E.

Ieva S.

Lazzarin M.

Magrin S.

Mazzotta Epifani E.

Micheli M.

Perna D.

Perozzi E.

Speziali R.

English

Archivio della ricerca - Università degli studi di Napoli &quot;Parthenope&quot;

Mem. S.A.It. Vol. 87, 83c© SAIt 2016 Memorie dellaThe NEOShield-2 EU project:the Italian contributionE. Dotto1, S. Ieva1, E. Mazzotta Epifani1, A. Di Paola1, M. Cortese1,2, R. Speziali1,M. Lazzarin3, I. Bertini3, S. Magrin3, D. Perna1,4, E. Perozzi2,5,6, and M. Micheli5,6,71 INAF-Osservatorio Astronomico di Roma, Via Frascati 33, I-00078 Monteporzio Catone,Roma, Italy, e-mail: elisabetta.dotto@oa-roma.inaf.it2 Deimos Space, Strada Buchesti 75-77, Bucharest, Romania3 Università di Padova, Vicolo dell’Osservatorio 3, I-35122 Padova, Italy4 LESIA – Obs.Paris, PSL Res. Univ., CNRS, Sorbonne Univ., UPMC Univ. Paris 06, Univ.Paris Diderot, France5 ESA-NEOCC, ESRIN, Via Galileo Galilei 64, I-00044 Frascati, Roma, Italy6 INAF-IAPS, Via Fosso del Cavaliere 100, 00133, Rome, Italy7 SpaceDys, Via Mario Giuntini 63, 56023 Cascina, Pisa, ItalyAbstract. The NEOShield-2 (2015-2017) project has been recently approved by theEuropean Commission in the framework of the Horizon 2020 programme with the aim i) tostudy specific technologies and instruments to conduct close approach missions to NEOs orto undertake mitigation demonstration, and ii) to acquire in-depth information of physicalproperties of the population of small NEOs (50-300 m), in order to design mitigation mis-sions and assess the consequences of an impact on Earth. The Italian scientific communityis widely involved in this project.Key words. Asteroids: photometry – NEOs1. IntroductionThe Near Earth Object (NEO) population com-prises both asteroids and comet nuclei on orbitswith perihelion distances q≤1.3 au, which peri-odically approach or intersect the Earth’s orbit.NEOs are responsible of a continuous flux ofimpactors with our planet: most meteorite falls(like the Chelyabinsk event in 2013) as wellas occasional major catastrophic impact events(like Tunguska in 1908),The physical characterization of NEOs isessential to define successful mitigation strate-gies in case of possible impactors. In fact,whatever the scenario, it is clear that the tech-nology needed to set up a realistic mitigationstrategy depends upon the knowledge of thephysical properties of the impacting object.Moreover, the knowledge of the physical andand chemical properties of the NEO popula-tion can give us crucial information about theearly evolution of the Solar System and the thedelivery of water and organics to the primitiveEarth.Unfortunately, about 95% of the 13000known NEOs, is still missing a compositionalcharacterization. In particular we have infor-84 Dotto et al.: The NEOShield-2 EU projectmation of only about 1.5% of the known smallobjects population (D<300 m) and their in-creasing discovery rate (more than 1000 ob-jects/year) makes the situation progressivelyworse.At a European level, the EuropeanCommission promoted the study on NEOsby approving and financing the NEOShieldproject. The NEOShield-1 project (2012–2015) has been set-up to provide detailed testmission designs to develop an actual deflectiondemonstration mission. The NEOShield-2(2015–2017) project has been recently ap-proved and financed in the framework of theHorizon 2020 program with the aim i) tostudy detailed technologies and instrumentsto conduct close approach missions to NEOsor to undertake mitigation demonstration,and ii) to retrieve the physical properties ofa wide number of NEOs, in order to designimpact mitigation missions and assess theconsequences of an impact on Earth.2. Observational activiesOne of the main goals of the NEOShield-2project is to undertake an extensive observa-tional campaign of a large number of NEOsin the 50–300 m size range. Photometric,spectroscopic and thermal infrared observa-tions have to be carried out using guaranteedrapid access to worldwide telescopes owned byNEOShield-2 consortium members (12 tele-scopes in the 1–2 m size range, 2 in the 3–4m, and 1 in the 8 m), as well as by competitiveproposals to get access to medium/large tele-scopes and very large telescopes (see Table I).A negotiation for purchase of observationaltime at ESO NTT 3.5 m telescope (La Silla,Chile) has been successfully carried out. Anagreement has been signed by ESO and theParis Observatory (1st March 2015) to useESO/NTT and 30 nights have been allocated tothis project. A Guaranteed time proposal hasbeen accepted (program 095.C-0087, P.I. D.Perna): VIS/NIR spectroscopy (+photometry).7 nights have been already allocated (April,June, July 2015).In the framework of the EU projectNEOShield-2, the Italian community is re-sponsible of the Task 10.2.1 – Colours andPhase function, which has the aim to acquirephotometric measurements in order to:1. perform a preliminary taxonomic classifi-cation using computed color indexes andhave the first constraints on the surfacecomposition and albedo of the observedobjects. It is important to note that bydiscriminating between C- and V- class(which have mean albedo of 0.13 and 0.43respectively) we can reduce the uncertaintyon diameter of about 300% and conse-quently reduce about 20 times the uncer-tainty on the impact energy;2. study the phase function, and to derive thecorrect β and G parameters; these valueswill be used to better compute the absolutemagnitude and hence to estimate albedoand diameter. The obtained phase functionswill also give an independent confirmationof the taxonomic classification;3. obtain information on the surface physicalproperties (e.g. regolith, thermal inertia, ...)through the combination of the results ob-tained in the visible bands with thermal in-frared observations, already planned in theframework of the NEOShield-2 project;4. contribute to the estimation of the responseto non-gravitational forces (mainly to theYarkovsky effect), through the estimate ofthe internal density, and therefore modelthe future dynamical evolution of the ob-served bodies.An operational interface is maintained to-gether with the ESA NEO Coordination Centre(NEOCC, http://neo.ssa.esa.int) in order to op-timize observations devoted to physical char-acterization.The Italian team is guaranteeing observa-tions throughout rapid access to Italian tele-scopes and facilities (e.g. Campo Imperatore,Asiago), as well as by competitive proposals toget access to medium/large and very large tele-scopes (e.g. TNG, LBT, and VLT). 24 hoursare already allocated at TNG in the September2015 – February 2016 semester.Dotto et al.: The NEOShield-2 EU project 85Table 1. Available TelescopesTelescope, site Diameter Wavelength AvailabilityPhotometry (lightcurve, colors)T1M, Pic du midi (F) 1.06 m VIS Guaranteed (OBSPM),quick responseOHP, Haute Provence (F) 1.2 m VIS Easy access (by OBSPMproposals)SCHMIDT, Campo Imperatore (I) 60/90 cm VIS Guaranteed (INAF),quick responseAZT24, Campo Imperatore (I) 1.10 m JHK bands Guaranteed (INAF),quick responseLBT, Mount Graham (Arizona, USA) 8.4 m VIS/NIR Guaranteed easy access(<2.5µm) (under discussion, INAF)TNG, La Palma, Canary Islands (E) 3.58 m VIS/NIR Guaranteed easy access(<2.5µm) (INAF)Pan-STARRS 2 x 1.8 m VIS Guaranteed survey dataaccess (QUB)LT, La Palma, Canary Islands (E) 2.0 m VIS/NIR Competitive proposal(QUB)SQT, La Palma, Canary Islands (E) 1.0 m VIS Guaranteed easy access(QUB)SCHMIDT, Asiago (I) 67/92 cm VIS Guaranteed (INAF), quickresponseTGO, Les Makes, LaReunion (F) 60 cm VIS Guaranteed (OBSPM), quickresponse1-meter, Calern (F) 1.0 m VIS Guaranteed (CNRS), quickresposeOASI, Itacuruba (BR) 1.0 m VIS Guaranteed (incollaboration with ONBrazil), quick resposeLijang Station (Yunnan, CN) 2.4 m VIS Easy access (by proposals)NTT, La Silla (RCH) 3.5 m VIS/NIR Time slots during(<2.5µm) spectroscopic observationsVIS/NIR SpectroscopyTNG, La Palma, Canary Islands (E) 3.58 m VIS/NIR Competitive proposals(<2.5µm)NTT, La Silla (RCH) 3.5 m VIS/NIR Purchase of 30-35 nights(<2.5µm)IRTF, Mauna Kea (Hawaii, USA) 3.0 m NIR (0.8-2.4 Competitive proposalsµm, SpeXSOAR, Cerro Pechon (RCH) 4.1 m VIS/NIR Competitive proposals(<2.5µm) collaboration with ONBrazil)VLT, Paranal (RCH) 8.2 m VIS/NIR Competitive proposals(<5µm)LBT, Mount Graham (Arizona, USA) 8.4 m VIS/NIR Competitive proposals(<2.5µm)Galileo, Asiago (I) 1.22 m VIS Guaranteed (INAF), quickresponseThermal InfraredGTC, La Palma, Canary Islands (E) 10.4 m 7.5-25 µm Competitive proposalsVLT, Paranal (RCH) 8.2 m 7.5-25 µm Competitive proposals86 Dotto et al.: The NEOShield-2 EU project3. ConclusionIn the course of the whole NEOShield-2project, we estimate to obtain informationon size, shape, rotation, composition, regolithproperties and albedo of a great number ofNEOs, throughout photometric, spectroscopicand thermal IR observations. This large sampleof data acquired with the same instrumentationand analyzed by the same scientific team willminimize several bias effects present in the lit-erature data, and will allow us for the first timeever to carry out an in-deep statistical study ofthe small NEA population.The NEOShield-2 project will undertake –for the first time ever – a significant and com-prehensive characterization of the small NEOpopulation, to study their typical mitigation-relevant physical properties (size, albedo, min-eralogy, shape, density, internal structure).Such information will establish a new bench-mark of knowledge and understanding of thephysical properties of NEOs and will also beof huge scientific relevance to model the NEOpopulation for a better determination of theearly evolutionary phases of our solar system.Acknowledgements. We aknowledge financial sup-port from the NEOShield-2 project, funded by theEuropean Commission’s Horizon 2020 programme(Contract No. PROTEC-2-2014-640351).

The NEOShield-2 EU project: The Italian contribution

https://ricerca.uniparthenope.it/bitstream/11367/88153/1/2016MmSAI__87___83D.pdf

The NEOShield-2 EU project: The Italian contribution

Abstract

Similar works

Full text

Available Versions

Archivio della ricerca - Università degli studi di Napoli "Parthenope"

The NEOShield-2 EU project: The Italian contribution

Abstract

Similar works

Full text

Available Versions

Archivio della ricerca - Università degli studi di Napoli &quot;Parthenope&quot;

Archivio della ricerca - Università degli studi di Napoli "Parthenope"