A carbon planet is a hypothetical type of planet that contains more carbon than oxygen. Carbon is the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen.

Marc Kuchner is an American astrophysicist, a staff member at NASA's Goddard Space Flight Center (GSFC) known for work on images and imaging of disks and exoplanets. Together with Wesley Traub, he invented the band-limited coronagraph, a design for the proposed Terrestrial Planet Finder (TPF) telescope, also to be used on the James Webb Space Telescope (JWST). He is also known for his novel supercomputer models of planet-disk interactions and for developing the ideas of ocean planets, carbon planets, and helium planets. Kuchner appears as an expert commentator in the National Geographic television show "Alien Earths" and frequently answers the "Ask Astro" questions in Astronomy Magazine. He currently serves as the principal investigator of the citizen science websites Disk Detective and Backyard Worlds.