Robert Grant Aitken (December 31, 1864 – October 29, 1951) was an American astronomer.
He worked at Lick Observatory in California. He systematically studied double stars, measuring their positions and calculating their orbits around one another. He methodically created a very large catalog of such stars, which was published in 1932 and entitled New General Catalogue of Double Stars Within 120o of the North Pole, with the orbit information enabling astronomers to calculate stellar mass statistics for a large number of stars. Aitken also measured positions and computed orbits for comets and natural satellites of planets.
Read The Binary Stars by Robert Grant Aitken, free from Google Books.
He was elected to serve as president in 1899 and 1915 of the Astronomical Society of the Pacific.
Aitken was partly deaf and used a hearing aid. He married Jessie Thomas around 1888, and had three sons and one daughter. His grandson, Robert Baker Aitken, was a widely-known Zen Buddhist teacher and author.