拉直后的星系M51
2020年8月21日 Unwinding M51 Image Credit & Copyright: Data – Hubble Heritage Project, Unwinding – Paul Howell Explanation: The arms of a grand design spiral galaxy 60,000 light-years across are unwound in this digital transformation of the magnificent 2005 Hubble Space Telescope portrait of M51. In fact, M51 is one of the original spiral nebula...