CAPE CANAVERAL, Fla. -- Astronomers have discovered the earliest seeds of rocky planets forming in the gas around a baby sun-like star, providing a precious peek into the dawn of our own solar system. It’s an unprecedented snapshot of “time zero,” scientists reported Wednesday, when new worlds begin to gel.

When scientists want to understand the earliest history of our Solar System, they’ve typically turned to ancient meteorites. These celestial objects that come to Earth are remnants of the building blocks of the planets,