Annie Jump Cannon was an American astronomer born on December 11, 1863, in Dover, Delaware. She is best known for her work in stellar classification, where she developed the Harvard Classification Scheme that categorizes stars based on their temperatures and spectral types. Cannon's contributions significantly advanced the field of astronomy and helped in understanding the properties of stars. Throughout her career, Cannon classified over 350,000 stars, making her one of the most prolific astronomers of her time. She was part of the Harvard Observatory team, which included other notable women astronomers like Henrietta Leavitt and Williamina Fleming. Cannon's work laid the foundation for modern astrophysics and earned her recognition in the scientific community.