Born on This Day: January 20

Italian mathematician whose systematic treatment of complex numbers advanced algebra and mathematical notation.

German astronomer whose observations contributed to early telescopic astronomy and the study of Jupiter’s moons.

American chief justice whose decisions established judicial review and strengthened the constitutional role of the Supreme Court.

French physicist and mathematician whose work founded electrodynamics; the ampere unit is named for him.

American folk and blues musician whose repertoire and recordings preserved songs that influenced generations of performers.

Italian filmmaker whose imaginative visual language and autobiographical storytelling transformed world cinema.

American astronaut and engineer who became the second person to walk on the Moon and has promoted space exploration and science education.