Tightly wound, almost concentric, arms of dark dust encircle the bright nucleus of galaxy NGC 2787 in this NASA Hubble Space Telescope image created by the Hubble Heritage Team.
In astronomer Edwin Hubble's galaxy classification scheme, NGC 2787 is classified as an SB0, a barred lenticular galaxy. These lens-shaped galaxies show little or no evidence of the grand spiral arms that occur in their more photogenic cousins, though NGC 2787 does sport a faint bar, not apparent in this image.
NGC 2787's seemingly bland qualities are, however, just what the doctor ordered for astronomer Marcella Carollo's investigation. Dr. Carollo (Swiss Federal Institute of Technology, Zurich) and team used Hubble to look at the center of these galaxies for clues about the process of galaxy formation including the role of galaxy collisions and central black holes.
Also visible in the Heritage image are about a dozen globular clusters hovering around NGC 2787. What appear to be stars are, in fact, gravitationally bound families of 100,000's of ancient stars orbiting the center of NGC 2787.
NGC 2787 lies roughly 24 million light-years (7.4 megaparsecs) from Earth in the constellation Ursa Major. Data was collected with the Wide Field Planetary Camera 2 in January 1999. This Heritage image was made by combining light from blue, green and infrared filters from the 1999 dataset.
Object Name: NGC 2787
April 4, 2002
Why are astronomers studying this galaxy?
Astronomers are looking at the centers of barred lenticular galaxies like NGC 2787 for clues about the process of galaxy formation, including the role of galaxy collisions and central black holes.
Also visible in the Heritage image are about a dozen globular clusters hovering around NGC 2787. What appear to be stars are, in fact, gravitationally bound families of hundreds of thousands of ancient stars orbiting the center of NGC 2787.
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