Two Galaxies in One
Observations from NASA's Spitzer Space Telescope show that the Sombrero galaxy is actually two galaxies in one. With a halo of stars surrounded by the thin edge of a stellar disk, the galaxy resembles a big hat. But by observing in infrared wavelengths, Spitzer was able to look through the galaxy's dust, revealing a halo that is big and massive enough to be considered a full-fledged elliptical galaxy.
"Spitzer is helping to unravel secrets behind an object that has been imaged thousands of times," said Sean Carey of NASA's Spitzer Science Center at Caltech. "It is intriguing Spitzer can read the fossil record of events that occurred billions of years ago within this beautiful and archetypal galaxy."
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