Credit: NASA/JPL-Caltech/L. Allen (Harvard-Smithsonian CfA)

Now You See Stars, Now You Don't

The image composite compares an infrared image taken by NASA's Spitzer Space Telescope to a visible-light picture of the same region (inset). While the infrared view, dubbed "Mountains of Creation," reveals towering pillars of dust aglow with the light of embryonic stars (white/yellow), the visible-light view shows dark, barely-visible pillars. The added detail in the Spitzer image reveals a dynamic region in the process of evolving and creating new stellar life.

Why do the pictures look so different? The answer has two parts. First, infrared light can travel through dust, while visible light is blocked by it. In this case, infrared light from the stars tucked inside the dusty pillars is escaping and being detected by Spitzer. Second, the dust making up the pillars has been warmed by stars and consequently glows in infrared light, where Spitzer can see it. This is a bit like seeing warm bodies at night with infrared goggles. In summary, Spitzer is both seeing, and seeing through, the dust.

The Spitzer image was taken by the infrared array camera on Spitzer. It is a 4-color composite of infrared light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange), and 8.0 microns (red).

The visible-light image is from California Institute of Technology's Digitized Sky Survey.

About the Object	Object Name: "Mountains of Creation" in W5 Region Object Type: star-forming region Position (J2000): RA: 3h01m56s Dec: +60d35m50s Distance: 2000 pc; 7000 light-years Constellation: Cassiopeia
About the Data	Image Credit: NASA/JPL-Caltech/L. Allen (Harvard-Smithsonian CfA) Instrument: IRAC Wavelength: 3.6 (blue), 4.5 (green), 5.8 (orange), 8.0 (red) microns Field of View: 34 x 26 arcminutes Orientation: North is 84 deg CCW from up Release Date: November 9, 2005
Observers	Lori Allen (Harvard-Smithsonian CfA) Joseph Hora (Harvard-Smithsonian CfA) Luis Chavarria (Harvard-Smithsonian CfA) Lynne Deutsch (Harvard-Smithsonian CfA)

Individual Images

	Spitzer image (full field) Screen-Resolution (450x335): JPEG High-Resolution (3426x2548): JPEG | Mac TIFF | PC TIFF Credit: NASA/JPL-Caltech/L. Allen (Harvard-Smithsonian CfA)
	Visible-light comparison image Screen-Resolution (450x335): JPEG High-Resolution (3426x2548): JPEG | Mac TIFF | PC TIFF Credit: DSS

The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory. This website is maintained by the Spitzer Science Center, located on the campus of the California Institute of Technology and part of NASA's Infrared Processing and Analysis Center.