Anders Lindstedt Anders Lindstedt Anders Lindstedt (27 June 1854 – 16 May 1939) was a Swedish mathematician, astronomer, and actuarial scientist, known for the Lindstedt-Poincaré method. Lindstedt was born in a small village in the district of Sundborns, Dalecarlia a province in central Sweden. He obtained a PhD from the University of Lund aged 32 and was subsequently appointed as a lecturer in astronomy. He later went on to a position at the University of Dorpat (then belonging to Russia, now University of Tartu in Estonia) where he worked for around seven years on theoretical astronomy. He combined practical astronomy with an
Stephen Alexander (astronomer) Stephen Alexander (astronomer) Stephen Alexander (September 1, 1806 – June 25, 1883) was a noted astronomer and educator. He was born in Schenectady, New York. He was the brother-in-law of Joseph Henry, the first secretary of the Smithsonian, and worked closely with him. He graduated from Union College in 1824. He became a tutor in mathematics at Princeton University in 1832; he would later become professor of astronomy and mathematics and advocate for the construction of Princeton's first observatory. Alexander relied on the assistance of a free African American man named Alfred Scudder, who worked for him at Princeton during