Asaph Hall Jr.

Hall received his Ph.D. in 1889 from Yale University when he submitted his thesis explaining the mass of Saturn and the orbit of Titan.

[2] One of his more notable students who he worked closely with at the Detroit Observatory through the University of Michigan was Harriet Williams Bigelow.

[6][7] Hall made this determination with the newly repaired Meridian Circle, by examining zenith distances from Polaris.

[2] This was one of the crowning achievements of his career at the University of Michigan, both for his repairs performed on the Meridian Circle, which was in poor condition prior, and for the scientific impact his determination of the constant of aberration.

In 1908, Hall was promoted to Professor of Mathematics at the rank of Commander in the Navy, at which point he took over all equatorial research for the Observatory.

[2] Included in this, was his work on the orbits of planetary satellites[8] using the 26-inch (66-cm) telescope, the great refractor of his father's discoveries.

Hall's childhood home, in the Georgetown neighborhood of Washington, D.C. Note his mother Angeline on front steps, and two Black workers. The house later served as the parsonage and fellowship hall of Alexander Memorial Baptist Church .