From the July 2008 issue

What is a Bok globule?

Sam Platts, Sylmar, California
By | Published: July 28, 2008 | Last updated on May 18, 2023



What is a Bok Globule?

Sam Platts

Sylmar, California

A Bok globule is a compact dark nebula first recognized by Dutch-American astronomer Bart Bok (1906–1983). Dust makes up about 1 percent of these clouds by mass. Cold gas constitutes the rest. Because these patches are so dense, they blot out much of the background light behind them, giving them an inky black appearance. 

Many bright nebulae contain Bok globules. They can take different shapes because radiation from nearby hot, young stars erodes and sculpts them. Many globules also appear to be collapsing, which suggests they are on their way to making new stars.

Michael E. Bakich

Senior Editor