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The Pinwheel Galaxy, M101, in the Infrared
Ssc2008 14b

Credit: NASA/JPL-Caltech

Observation • July 21st, 2008 • ssc2008-14b


The tangled arms of the Pinwheel galaxy, otherwise known as Messier 101, are decked out in red in this new infrared image from NASA's Spitzer Space Telescope.

The Pinwheel galaxy is located 27 million light-years away in the constellation Ursa Major. It is what's called a flocculent spiral, which means that its spiral arms are not well defined.

In this infrared composite, the red color shows the dust, while the blue glow around the galaxy is from starlight. Blue indicates light with a wavelength of 3.6 microns, green corresponds to 4.5 microns, and red to 5.8 and 8.0 microns. The contribution from starlight (measured at 3.6 microns) has been subtracted from the 5.8- and 8-micron images to enhance the visibility of the dust features.

About the Object

Pinwheel galaxyM101Messier 101NGC 5457
Galaxy > Type > Spiral
Galaxy > Component > Disk
21,440,000 Light Years

Color Mapping

Band Wavelength Telescope
Infrared 3.6 µm Spitzer IRAC
Infrared 4.5 µm Spitzer IRAC
Infrared 8.0 µm Spitzer IRAC


Position (J2000)
RA =14h 3m 12.3s
Dec = 54° 20' 54.9"
Field of View
28.1 x 28.1 arcminutes
North is 35.0° left of vertical