Not to be confused with host of the
Daily Show Jon Stewart, John Stewart was one of
Earth's
Green Lantern's in the
DC comic book of the same name.
The Guardians give every sector of the Universe a Green Lantern. Hal Jordan was Earth's (sector 2814). Every Green Lantern gets a power ring that gives them super powers. Every Lantern must also choose a backup. Guy Gardner was Hal's backup. When he was injured, the Guardians chose Stewart as the new backup.
John's first appearence was in the second series of Green Lantern comics, issue # 87. He is the least notable of all of Earth's Green Lanterns. However, he was recently chosen to be one of the stars of the Bruce Timm's new JLA cartoon. Many speculate this is because the Justice League is missing an African American presence, and Stewart is one of the few black DC characters who could have filled it.