Year of the Comet
Comet C/2011 L4 (PANSTARRS)

PANSTARRS information

Comet C/2012 S1 (ISON)

ISON information

Ask Astro

Published: July 27, 2009
September 2009 Sombrero Galaxy
A spherical “bulge” of stars illuminates the center of the Sombrero Galaxy (M104) in this visible-light portrait captured by the Hubble Space Telescope.
Photo by NASA/Hubble Heritage Team (STScI/AURA)
It depends on the galaxy. Many large galaxies contain a central concentration of bright stars. Other galaxies have extremely luminous cores because a central supermassive black hole is consuming matter and radiating energy.
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