Rising Sun is a human solar battery, recharging his powers from sunlight. He can create solar winds, heat and light. His power over magnetic fields enables him to fly.
Isumi Yasunari's grandparents both survived the Nagasaki atom bomb by the US on Japan in 1945. However, as a result of the bombing, they both developed cancer and died. Isumi's mother also developed cancer, but was healed through chemotherapy treatment. Horrified by the genetic condition of his family, Isumi and his brother both became Doctors of Medicine, specializing in cancer research. Meanwhile, their troubled sister Kaori joined a religious sect.
Isumi used his abilities to absorb solar radiation and become Rising Sun, a staunch defender of Japan, who believes his country should adopt a less pacifistic role and attitude in world affairs. He is a member of the Global Guardians and has faithfully served them for a number of years. He is also romantically interested in Doctor Light II.
The Rising Sun's exploits are not well known in the media. His first appearance was helping the Atom dismantle a bomb in Japan. He has aided Robin and helped Superman locate a piece of ancient armor. He and the other Guardians help Superman battle ancient sorcerers amid the Statues of Easter Island. He helps save many people and lands during the Crisis on Infinite Earths. He helps Artemis save her parents Huntress and Sportsmaster.
He tries to aid The Queen Bee and he is brainwashed into attacking Power Girl and Rocket Red. He lapses into a coma when he loses and is brought out of a coma while being cared for at the JLI embassy in Tokyo, Japan. When the brainwashing is reversed and Sumaan is captured the Leaguers and Guardians go their separate ways. He is able to keep the Guardians regrouped after their defeat to Fain Y'onia.
He and Doctor Light start a relationship. He makes a retrospective piece about Big Science Action, a documentary about the Japanese super heroes and The JLA battle Fushikaraje who almost destroyed Japan to get to an underground graveyard under Mt. Fuji. He later begins to berate the Super Young Team, a new group of Japanese crimefighters. They soon realize Mr. Mind is controlling him.
He is 5 ft 9 in tall, he weighs 162 lbs his eyes are brown and his hair is black.