Bart Jan Bok (Hoorn, April 28 1906 – Tucson, August 5 1983) was a Dutch-American astronomer.

He was born in the Netherlands, educated at the Leiden and Groningen Universities, but worked at Harvard University from 1929–1957. He then worked as director of Mount Stromlo Observatory in Australia for nine years, before returning to the United States as director of Steward Observatory. He became a US citizen in 1938.

He won the Bruce Medal in 1977, and was awarded the Henry Norris Russell Lectureship in 1982, and the Klumpke-Roberts Award in that same year.

The Bok crater on the Moon is named after him, as is the asteroid 1983 Bok. There is a Bok crater on Mars as well, but it is named for a geographical location in Papua New Guinea and not for him.

Bok died of a heart attack in his home in Tucson, Arizona.

External links

• Bruce Medal page

Obituaries

• JRASC 78 (1984) 3
• JRASC 78 (1984) 8
• PASAu 5 (1984) 608
• QJRAS 28 (1987) 539