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La maggior parte dei 200’000 asteroidi che si trovano fra Marte e Giove, nella cosiddetta fascia principale, sono i frammenti di cinque o sei antichissimi pianeti andati in frantumi quando il Sistema Solare si stava ancora formando.
La scoperta, pubblicata sulla rivista Nature Astronomy, è importante per capire la loro storia e può aiutare anche a proteggere la Terra dai eventuali effetti.
"Meteoriti e asteroidi sfrecciano vicino al nostro pianeta. È quindi necessario preoccuparsi di quanti siano e di che tipo di materiali sono fatti" – ha commentato Stanley Dermott che ha guidato il gruppo di ricerca statunitense – "Se anche uno solo di questi arrivasse sulla Terra, e volessimo deviarlo, dobbiamo conoscere la sua natura".
I ricercatori hanno dimostrato che il tipo di orbita di un asteroide dipende dalle sue dimensioni. "Conoscere l'evoluzione dei corpi che hanno formato il nostro Sistema solare ci può aiutare a rispondere a domande su come possano esistere pianeti come il nostro nell'Universo", ha concluso Dermott.
ANSA/AnP
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