Watchmen character Jon Osterman is better known by what alias?

Watchmen character Jon Osterman is better known by the alias Doctor Manhattan, commonly written as Dr. Manhattan.

Jon Osterman begins the story as a German-American nuclear physicist working at a research facility in the fictional world of Watchmen. In 1959, he is accidentally trapped inside an Intrinsic Field Subtractor and physically disintegrated. Over the following weeks, he gradually reconstructs his body and emerges with extraordinary powers over matter, energy, and time.

The United States government gives him the name Doctor Manhattan, invoking the Manhattan Project and presenting him as a strategic symbol of American scientific power during the Cold War. His blue appearance and near-godlike abilities make him the only fully superpowered central character in the original graphic novel.

Doctor Manhattan is not the same character as Ozymandias, Rorschach, or Nite Owl. Those figures are masked or technologically enhanced vigilantes, while Manhattan’s abilities result from the laboratory accident. The character was created by writer Alan Moore and artist Dave Gibbons for the 1986–1987 Watchmen series.