NGC 3603 has the distinction of being one of the brightest and most active star formation regions in our galaxy. Now, astronomers using the Wide Field Imager at the ESO’s La Silla Observatory in Chile have gotten an unprecedented look into the cluster, revealing a dramatic display of glowing gases and some of the most massive — and violent — stars in the Milky Way.
NGC 3603 is located approximately 20,000 light-years from Earth and can be seen in the observation as the huge glowing nebulous object in the left of the image. The second nebula to the right, with large arcing tendrils of gas, is NGC 3576, which is actually closer to us — about half the distance from Earth.
In the core of NGC 3603 is a system of fascinating stars known as Wolf-Rayets called HD 97950. Wolf-Rayet stars are massive stars (around 20 times the mass of our sun) that are coming to the end of their lives. Rapidly burning all the available hydrogen gases in their cores, Wolf-Rayets are extremely unstable; powerful stellar winds blast huge quantities of stellar material from the stars’ upper layers. Eventually these stars will explode as supernovae.
Surrounding HD 97950 is a reddish cloud of glowing gas called an HII region. These beautiful structures are powered by ultraviolet radiation generated by young stars cocooned inside the stellar nursery. This particular HII region is several hundred light-years wide and is known to be the most massive in our galaxy.
The nearer NGC 3576, which is only 9,000 light-years from us, has large curved structures of gas generated by powerful stellar winds. Also inside the nebula are very dark silhouetted nebulae called Bok globules — probable locations of baby stars being born, but hidden from view by the globules’ thick gas and dust.