Asaph Hall

Asaph Hall's story is one of tenacity triumphing over humble beginnings. Largely self-educated after his father's death forced him to leave school at 13, he worked as a carpenter while studying mathematics and astronomy at night. His skill eventually earned him a position at the Harvard College Observatory and, later, a prestigious post at the U.S. Naval Observatory in Washington, D.C. It was there, using the Observatory's massive 26-inch refracting telescope—the largest of its kind in the world at the time—that Hall embarked on a deliberate hunt for Martian moons. The search was grueling; many astronomers had given up, convinced Mars had no satellites. After nights of fruitless scanning, he was ready to quit, but his wife, Angelina, urged him on. The very next night, on August 12, 1877, he spotted a faint point of light: Phobos. Days later, he found Deimos. This discovery cemented his legacy. Hall continued a distinguished career calculating the orbits of planetary satellites and double stars, and determining the mass of Mars, but his name is forever written in the sky around the red planet.