Fine-tuning galaxies with Herschel and Spitzer

Interactive Hubble Tuning Fork Galaxies come in all shapes and sizes: from those with compact fuzzy bulges or central bars to galaxies with winding spiral arms. Astronomer Edwin Hubble classified these different breeds of galaxies by means of a diagram known as the Hubble Tuning Fork. The tuning fork shape presents elliptical galaxies along the handle, and two different populations of spiral galaxies on the fork's 'prongs' to differentiate between spiral galaxies with a central bar, and those without. The diagram also describes the shape of the galaxies. Elliptical galaxies are positioned further along the handle towards the fork depending on how elongated they appear, while spiral galaxies are organised by how tightly wound their arms are. Of course, there are always exceptions, and a separate class of 'irregular' galaxies conforms to neither group, perhaps as a result of a collision or merging event disrupting their shape. In this interactive tuning fork diagram, 61 nearby galaxies studied by ESA's Herschel and NASA's Spitzer space telescopes are presented.