Un gruppo di 15 nuovi pianeti s’aggiunge alla folla di quasi 4'000 mondi scoperti negli ultimi anni oltre il sistema solare. Orbitano attorno a stelle piccole e fredde, le nane rosse.
Uno di loro, battezzato K2-155d, potrebbe essere una Terra in formato gigante (il suo raggio è di 1,6 volte maggiore) con tanto di acqua liquida disponibile, vista la distanza dal suo Sole.
Come riferisce l’Astronomical Journal, che pubblica i risultati di due ricerche, l’una condotta dall’Istituto di tecnologia di Tokyo grazie ai dati raccolti dal telescopio spaziale Kepler e l’altra partendo dalle osservazioni fatte alle Hawaii e in Spagna, restano da verificare alcune capitali condizioni prima di poter dire che questo corpo celeste situato a 200 anni luce da noi sia veramente ospitale.
ANSA/dg
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