原始 げんし惑星 わくせい けい円盤 えんばんだったら
genshi waku seikeiembandattara

Noun
Da Copula

The "-tara" conditional form ("if/when…") of 原始惑星系円盤

1. If it were a protoplanetary disk.; If it was a protoplanetary disk.

Tara Conditional
Astronomy