Former astronaut and U.S. Senator John Glenn is dead at age 95.

Multiple news sources reported Glenn was hospitalized this morning, but gave no details to what he was being treated for.

Born in 1921, he was the oldest person ever to have traveled into space.

He was a Marine Corps pilot, a former U.S. Senator and a personal friend of the Kennedy family.

Glenn was also one of the "Mercury Seven" in the 60's, a group of pilots selected to fly the first American space mission.

In February 1962, Glenn became the first American to orbit the Earth on the Friendship 7 mission.  Throughout his life, he was known as an advocate for space research.

John Glenn Mercury Mission
Official U.S. Senate portrait of John Glenn, 1990s.