Spitzer's View of Family Life in the North American Nebula

Stars at all stages of development, from dusty little tots to young adults, are on display in a new image from NASA's Spitzer Space Telescope.

This cosmic community is called the North American nebula. In visible light, the region resembles the North American continent, with the most striking resemblance being the Gulf of Mexico. But in Spitzer's infrared view, the continent disappears. Instead, a swirling landscape of dust and young stars comes into view.

Where did the continent go? The reason you don't see it in Spitzer's view has to do, in part, with the fact that infrared light can penetrate dust whereas visible light cannot. Dusty, dark clouds in the visible image become transparent in Spitzer's view. In addition, Spitzer's infrared detectors pick up the glow of dusty cocoons enveloping baby stars. Some areas of this nebula are still very thick with dust and appear dark even in Spitzer's view. For example, the dark "river" in the lower left-center of the image.

The Spitzer image contains data from both its infrared array camera and multiband imaging photometer. Light with a wavelength of 3.6 microns has been color-coded blue; 4.5-micron light is blue-green; 5.8-micron and 8.0-micron light are green; and 24-micron light is red.

This new view of the North American nebula combines both visible and infrared light observations, taken by the Digitized Sky Survey and NASA's Spitzer Space Telescope, respectively, into a single vivid picture.

 The nebula is named after its resemblance to the North American content in visible light, which in this image is represented in blue hues. Infrared light, displayed here in red and green, can penetrate deep into the dust, revealing multitudes of hidden stars and dusty clouds. Only the very densest dust clouds remain opaque, like the dark bands seen in the "Gulf of Mexico" area.

Changing Face of the North American Nebula.

This image layout reveals how the appearance of the North American nebula can change dramatically using different combinations of visible and infrared observations from the Digitized Sky Survey and NASA's Spitzer Space Telescope, respectively.

In the bottom two images, only infrared light from Spitzer is shown -- data from the infrared array camera is on the left, and data from both the infrared array camera and the multiband imaging photometer, which sees longer wavelengths, is on the right. These pictures look different in part because infrared light can penetrate dust whereas visible light cannot. Dusty, dark clouds in the visible image become transparent in Spitzer's view. In addition, Spitzer's infrared detectors pick up the glow of dusty cocoons enveloping baby stars.

 

 This swirling landscape of stars is known as the North American nebula. In visible light, the region resembles North America, but in this new infrared view from NASA's Spitzer Space Telescope, the continent disappears.

Spitzer identified more than 2,000 new, candidate young stars in the region. There were only about 200 known before. Because young stars grow up surrounded by blankets of dust, they are hidden in visible-light images. Spitzer's infrared detectors pick up the glow of the dusty, buried stars. The new Spitzer image reveals all the stages of a star's young life, from the early years when it is swaddled in dust to early adulthood, when it has become a young parent to a family of developing planets.

The nebula's distance from Earth is also a mystery. Current estimates put it at about 1,800 light-years from Earth. Spitzer will refine this number by finding more stellar members of the North American complex.