Jacobus Kapteijn

Dutch astronomer born in 1851. Extensively studied the Milky Way & discovered evidence for galactic rotation.

Johannes Kepler

German astronomer, mathematician, astrologer, & key figure in the 17th-century scientific revolution.

Edwin Hubble

American astronomer born in 1889. Helped establish fields of extragalactic astronomy & observational cosmology.

Edmond Halley

English astronomer, geophysicist, mathematician, & physicist born in 1656. Halley’s Comet is named after him.

Edouard Roche

French astronomer & mathematician born in 1820 & known for his work in celestial mechanics.

Giorgio Abetti

Italian solar astronomer born in 1882. Crater Abetti on the moon is named after him.

Jean-Baptiste Morin

French mathematician, astrologer, & astronomer known for being a critic of Galileo & Descartes.

John Flamsteed

English astronomer & the first Astronomer Royal, born in 1646.

Percival Lowell

American businessman, author, mathematician, & astronomer born in 1855. Began the effort of discovering Pluto.

Ernest Esclangon

French astronomer & mathematician born in 1876. Initiated the first telephone speaking clock in 1933.