For the first time, astronomers have observed the initial phase in the formation of an earth-like planet. Astronomers observed that a protoplanetary disk, or ring, around the binary star known as KH 15D, is composed of solid particles larger than what is usually observed in space. For hundreds of years, scientists have been theorizing that Earth-like planets form when gas and dust around a star get compressed into these disks and the material begins to coalesce into planets.