Who has done missions in inner space as well as outer space?

Buzz Aldrin is one notable astronaut who has conducted missions in both inner space and outer space. He flew on the Gemini 12 mission, which involved significant underwater training and experiments in a controlled environment, representing "inner space." Aldrin is best known for his role as the lunar module pilot on Apollo 11, where he became one of the first humans to walk on the Moon, marking his achievements in outer space.