Come si presentava il sistema solare quattro miliardi di anni fa? La risposta potrebbe arrivare dalle osservazioni di un gruppo internazionale di ricercatori, tra cui astronomi del Politecnico di Zurigo, che hanno individuato nove "fabbriche di pianeti".
Si tratta di dischi di polveri e gas che ruotano attorno a giovani stelle, i cui materiali con il passare del tempo si aggregano per andare a formare uno o più pianeti.
I dischi individuati hanno caratteristiche diverse, per quanto riguarda grandezza e composizione, ma tutti forniscono indizi sulla formazione della Terra e degli altri pianeti che ruotano attorno al Sole.
ATS/sf
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