This image from NASA's Hubble Space Telescope shows nebula NGC 3603, a young star cluster surrounded by a vast region of dust and gas. Thousands of dazzling young stars nestle within one of the most massive young star clusters in the Milky Way Galaxy.

This prominent star-forming region lies in the Carina spiral arm of the Milky Way, about 20,000 light-years away.  

Ultraviolet radiation and winds from the bluest and hottest stars have pushed nebular gas away. Pillars of dense gas, embedded in the walls of the nebula, stretch a few light-years in height, and might incubate new stars.

At the top right lies a relatively small cluster of dark clouds called "Bok globules." These clouds are composed of dense dust and gas, and are about 10 to 50 times more massive than the Sun. A Bok globule may be undergoing a gravitational collapse on its way to forming new stars.

Sir John Herschel first discovered the nebula in 1834. This image spans roughly 17 light-years.

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-- NASA, ESA, and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration and SPACE.com Staff

Credit: NASA, ESA, and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration