Jan Oort

Jan Oort was a highly influential Dutch astronomer who made significant contributions to our understanding of the Milky Way. He was a professor at Leiden Observatory and established the dynamics of the galaxy's rotation in the 1920s.

The Oort cloud is a theoretical, distant spherical shell of icy bodies that surrounds our solar system. It was proposed by Jan Oort as the source of long-period comets that occasionally plunge into the inner solar system.

Yes, Jan Oort demonstrated in 1927 that the Milky Way galaxy is rotating. He achieved this by analyzing the statistical motions of stars, providing concrete evidence for galactic rotation.

Beyond the famous Oort cloud, asteroid 1691 Oort is named in his honor. Additionally, the Oort limit, which describes the edge of the Milky Way's gravitational influence, is named after his calculations.