Gallery: Space Photos of the Week: Purple Haze Star Cluster, All in Your Brain
<a href="http://www.nasa.gov/mission_pages/chandra/westerlund-2.html">NASA</a>01SPoW-Oct14-12.jpg
To celebrate American Archive Month, NASA’s Chandra X-ray Observatory has released a collection of images, including this shot of a cluster of stars 20,000 light years from Earth. The blue and green shows cosmic haze where clouds form; x-rays are shown in purple.
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This galaxy cluster is nicknamed the “Toothbrush Cluster”: the green stem is from radio waves, and the emission of purple toothpaste is from x-rays.
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This image depicts Colles Nili, a region on Mars, from above.
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This spiral galaxy is undergoing star formation, as seen in the blue knots, each marking a set of newborn stars.
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This image shows the rings of Saturn from above, with the darkened planet on the lower right. Even at night, the part of the rings not shadowed by Saturn remain in sunlight.
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Like cold fronts on Earth, merging galaxy clusters generate shock waves, shown in the white wave at the center of this image.
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These ancient stars, found in the middle of the Milky Way for the first time, may be from the biggest and oldest surviving cluster of stars in our galaxy.
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Supernovas explode approximately once every 50 years, leaving behind remnants like CTB 37A, located around 20,000 light years from Earth.
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The bright-white pulsar at the center of this image, located 12,000 light years from Earth, generated a trail of X-ray emission, as seen beneath it.
<a href="http://www.nasa.gov/feature/goddard/2016/hubble-reveals-observable-universe-contains-10-times-more-galaxies-than-previously-thought">NASA/ESA</a>10SPoW-Oct14-03.jpg
Images showing portions of large galaxies, like this one, help astronomers track galactic density: in the early universe, a set volume held 10 times as many galaxies as the same space would today.