This time-lapse movie of the Crab Nebula, made from NASA Hubble Space Telescope observations, reveals wave-like structures expanding outward from the "heart" of an exploded star. The waves look like ripples in a pond.
<p>The heart is the crushed core of the exploded star, or supernova. Called a neutron star, it has about the same mass as the sun but is squeezed into an ultra-dense sphere that is only a few miles across and 100 billion times stronger than steel. This surviving relic is a tremendous dynamo, spinning 30 times a second. The rapidly spinning neutron star is visible in the image as the bright object just below center. The bright object to the left of the neutron star is a foreground or background star.
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The movie is assembled from 10 Hubble exposures taken between September and November 2005 by the Advanced Camera for Surveys.
NASA and ESA; Acknowledgment: J. Hester (Arizona State University)
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