On this day in 1910 – November 11th – American astronomer Carl Alvar Wirtanen was born in Kenosha, Wisconsin.

Wirkenen worked at Lick Observatory in California. He's best known for his discovery of periodic comet 46P/Wirtanen and eight asteroids. On the comet's 2018 visit, it was dubbed the Christmas Comet. It was bright green, and visible in dark skies as a naked eye object. [Beautiful photo by Tommy Eliassen]

Mona Evans
For news, activities, pictures and more, sign up to the Astronomy Newsletter!