rex - arch

Editorial Use Only Mandatory Credit: Photo by NASA/JPL-Caltech/UCLA / Rex Features ( 1306637a ) Rho Ophiuchi might look like an abstract painting, but this splash of color is in fact a busy star-forming complex. WISE, NASA's Wide-field Infrared Explorer captured the picturesque image of the region, which is one of the closest star-forming complexes to Earth. Image captured by NASA's Wide-field Infrared Explorer - 2011 The amazing variety of colors seen in this image represents different wavelengths of infrared light. The bright white nebula in the center of the image is glowing due to heating from nearby stars, resulting in what is called an emission nebula. The same is true for most of the multi-hued gas prevalent throughout the entire image, including the bluish, bow-shaped feature near the bottom right. The bright red area in the bottom right is light from the star in the center--Sigma Scorpii--that is reflected off of the dust surrounding it, creating what is called a reflection nebula. And the much darker areas scattered throughout the image are pockets of cool, dense gas that block out the background light, resulting in absorption (or 'dark') nebulae. WISE's longer wavelength detectors can typically see through dark nebulae, but these are exceptionally opaque.