Skywatch

  • February 9, 2006

    Episode 22: Black Holes Grow

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    Shownotes

    Scientists are finding evidence that the black holes in the centers of galaxies grow over time as galaxies collide and merge with one another. Data from the Hubble Ultra Deep Field, an image that shows galaxies from an early period in the universe, can be compared with computer simulations to uncover clues that point toward black holes in young galaxies. Black holes seem to grow by pulling in stars, gas and dust from surrounding regions of the galaxy. Simulations show the centers of the young galaxies fluctuate in brightness. The fluctuations suggest that black holes may be gobbling stars and dust that spiral near the centers of the host galaxies. More of this material becomes available when the galaxies merge.