La intrépida prueba de Herschel: un atisbo de lo que vendrá   Three-colour far-infrared image of M51, the ‘whirlpool galaxy’. Red, green and blue correspond to the 160-micron, 100-micron and 70-micron wavelength bands of the Herschel’s Photoconductor Array Camera and Spectrometer, PACS. Glowing light from clouds of dust and gas around and between the stars is visible clearly. These clouds are a reservoir of raw material for ongoing star formation in this galaxy. Blue indicates regions of warm dust that is heated by young stars, while the colder dust shows up in red.   Comparison of M51 imaged with the Spitzer Space Telescope (left panel) and an image of the same galaxy taken with the Herschel Space Observatory (right panel), launched just a month ago. The obvious advantage of the larger size of the telescope is clearly reflected in the much higher resolution of the image: Herschel reveals structures that cannot be discerned in the Spitzer image. Both images were taken at the wavelength of 160 microns.   Far-infrared image of M 51, the ‘whirlpool galaxy’ at three different wavelengths (160, 100 and 70 microns) , taken by the Herschel Photoconductor Array Camera and Spectrometer, PACS. These images clearly demonstrate that the shorter the wavelength, the sharper the image — this is a very important message about the quality of Herschel’s optics, since PACS observes at Herschel’s shortest wavelengths. Release date: 22 junio 2009