Posthuman Blues

Terrestrial Planet Forming?

Are we seeing an Earth -- or at least a Mars-sized world -- in the making? Look no further than HD 113766, a binary system perhaps ten million years old some 424 light years away, for the story. One of its stars contains a warm dust belt that may be undergoing planetary formation. If that's the case, the emerging planet will orbit in the classical habitable zone, defined as that region where liquid water can exist on the surface.