New and Improved! The Hubble Sequence Revised

File this one under "one more thing that requires us to re-learn what we learned in school about galaxies". You've probably seen the "Hubble sequence" in astronomy books. It looks like a tuning fork, and has been thought of as a way not only to describe and classify galaxies, but possibly explain their evolutionary tracks as well. The original scheme, named for Edwin Hubble, was based on galaxies relatively close by in space.With more powerful modern telescopes able to image galaxies at much greater distances, and further back in time, astronomers have been constructing a new Hubble sequence for populations of galaxies that existed when the Universe was much younger, and find it to be remarkably different. The image below demonstrates the differences in galaxy morphology and the proportion of types between local galaxies and those six billion light years away.Image credit: NASA, ESA, Sloan Digital Sky Survey, R. Delgado-Serrano and F. Hammer (Observatoire de Paris)(Click on the image to enlarge)The two sections show how many more peculiar shaped galaxies (marked Pec) are seen among distant galaxies, as opposed to local galaxies. Researchers found that 3 percent of galaxies were elliptical (marked E), 15 percent lenticular (marked S0), 72 percent ...