The
Pinwheel galaxy sports a blue center and red outer ring, as seen in infrared light by
NASA’s Spitzer Space Telescope.
Also
known as Messier 101, the galaxy is located 27 million light-years away in the
constellation Ursa Major. Metal elements concentrate near the center of the
galaxy where fiery stellar furnaces produce them, but are much sparser in the
galaxy’s outer parts.
The
outer ring stands out as a zone where organic molecules called polycyclic
aromatic hydrocarbons, which exist throughout most of the galaxy, suddenly
disappear.
"If
you were going look for life in Messier 101, you would not want to look at its
edges," said Karl Gordon of the Space Telescope Science Institute in
Baltimore, Md. "The organics can't survive in these regions, most likely
because of high amounts of harsh radiation."
— NASA/JPL-Caltech/STScI and SPACE.com
Staff
Credit: NASA/JPL-Caltech/STScI
Return each weekday for a new SPACE.com Image of the Day.
| 
