Star Boy is Thom Kallor, a member of the Legion of Super-Heroes in the 30th Century. Born on the planet Xanthu, he has the special ability to increase any object's gravity or density or mass. His romantic partner and later wife is Dream Girl. He has also been a member of the Legion of Substitute Heroes. Following Infinite Crisis he traveled into the past, where his schizophrenia went untreated. He took the civilian identity Danny Blaine and became a member of the Justice Society as Starman.
In Reboot Legion continuity, Star Boy is the Legion's replacement for Kid Quantum. Xanthu later leaves the United Planets, and Star Boy joins the Uncanny Amazers. In Prime Legion continuity, Star Boy is portrayed as black. Star Boy was created by Otto Binder and George Papp, first appearing in Adventure Comics #282. (1961)