ジェームズ・クレイグ・ワトソン
He was awarded the James Craig Watson Medal in 1913. The year of 1920 Kapteyn took a part-time job at University of Leiden after leaving the university of Groningen. This move made Kapteyn able to see his granddaughter Rigel and his daughter Henrietta. In Kapteyn's later years of work he spent his time working on the combination of his life's work revising and editing the Kapteyn Universe. Kapteyn later retired in 1921 at the age of seventy, but on the request of his former student and director of Leiden Observatory Willem de Sitter, Kapteyn went back to Leiden to assist in upgrading the observatory to contemporary astronomical standards.