Christine Pulliam (CfA). Sun image: NASA/SDO
In this artist's conception, a carbon planet orbits a sunlike star in the early universe. Young planetary systems lacking heavy chemical elements but relatively rich in carbon could form worlds made of graphite, carbides and diamond rather than Earth-like silicate rocks. Blue patches show where water has pooled on the planet's surface, forming potential habitats for alien life.
Credit: Christine Pulliam (CfA). Sun image: NASA/SDO
