Spiral Galaxy M66
The barred-spiral galaxy Messier 66 (or M66 for short) is the largest galaxy in the "Leo Triplet" of galaxies, and trio of galaxies in the constellation of Leo. M66 is a barred spiral galaxy, which means it has spiral arms, in this case two large ones, connected by a bar running through the centre of the galaxy. The spiral arms are being pulled out of shape by the two nearby galaxies which complete the triplet. Herschel is not seeing the stars in the spiral arms and the bar, but instead the dust and gas which are being heated up by the stars.
In the background of the image, there are dozens of smaller blobs. These are not image artefacts, or even foreground stars, but much more distant galaxies - too far away for Herschel to see other than as small fuzzy blobs. Observations with SPIRE provide information on how warm and how far away the galaxies are, as well as an estimate of how much star formation is occuring in each galaxy.
The image on the left is a comparison of the previous best image at far-infrared wavelengths, taken by NASA's Spitzer satellite. Herschel has a much larger mirror (3.5m compared with 0.7m) and so can see the galaxy in much finer resolution.
French Herschel site
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