Alfred Harrison Joy

Alfred Harrison Joy was an astronomer. He was born on September 23, 1882, in Greenville, Illinois and died on April 18, 1973, in Pasadena, California.

Joy studied stars. He looked at how far stars are from Earth, how they move, and how some stars change in brightness. His work helped scientists learn more about the universe. A crater on the Moon was named after him to honor his important contributions to science.

Early years

Alfred Harrison Joy was born in Greenville, Illinois. His father, F.P. Joy, was a well-known clothing merchant and also served as the town’s mayor. Alfred went to school at Greenville College and graduated with a BA in 1903. The next year, he earned an MA from Oberlin College.

Career

After finishing his studies, Joy taught astronomy and led the observatory at the American University of Beirut. He had to leave in 1915 because of World War I.

Later, he joined the Mount Wilson Observatory in the United States, where he worked until 1952. There, he helped learn important facts about many stars, like what they are like, how far away they are, and how they move. He also studied how the light from stars changes to understand more about them. In 1950, he received the Bruce Medal for his work. He also served as president of the Astronomical Society of the Pacific in 1931 and 1939.