MSGID: 1:153/757.0 ad031cd6   
   TZUTC: -0700   
   CHRS: LATIN-1 2   
                           Astronomy Picture of the Day   
      
       Discover the cosmos! Each day a different image or photograph of our   
         fascinating universe is featured, along with a brief explanation   
                       written by a professional astronomer.   
      
                                  2023 October 6   
      
                        Edwin Hubble Discovers the Universe   
        Image Credit & Copyright: Courtesy Carnegie Institution for Science   
      
      Explanation: How big is our universe? This question, among others, was   
      debated by two leading astronomers in 1920 in what has since become   
      known as astronomy's Great Debate. Many astronomers then believed that   
      our Milky Way Galaxy was the entire universe. Many others, though,   
      believed that our galaxy was just one of many. In the Great Debate,   
      each argument was detailed, but no consensus was reached. The answer   
      came over three years later with the detected variation of single spot   
      in the Andromeda Nebula, as shown on the original glass discovery plate   
      digitally reproduced here. When Edwin Hubble compared images, he   
      noticed that this spot varied, and on October 6, 1923 wrote "VAR!" on   
      the plate. The best explanation, Hubble knew, was that this spot was   
      the image of a variable star that was very far away. So M31 was really   
      the Andromeda Galaxy -- a galaxy possibly similar to our own. Annotated   
      100 years ago, the featured image may not be pretty, but the variable   
      spot on it opened a window through which humanity gazed knowingly, for   
      the first time, into a surprisingly vast cosmos.   
      
                     Tomorrow's picture: once and future stars   
        __________________________________________________________________   
      
          Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)   
               NASA Official: Phillip Newman Specific rights apply.   
                   NASA Web Privacy Policy and Important Notices   
                         A service of: ASD at NASA / GSFC,   
                              NASA Science Activation   
                                & Michigan Tech. U.   
      
   --- BBBS/Li6 v4.10 Toy-6   
    * Origin: The Rusty MailBox - Penticton, BC Canada (1:153/757)   
   SEEN-BY: 1/123 15/0 90/1 105/81 106/201 123/131 129/305 134/100 153/135   
   SEEN-BY: 153/143 757 802 6809 7715 218/700 840 221/1 6 226/30 227/114   
   SEEN-BY: 229/110 112 113 206 307 317 400 426 428 470 664 700 240/1120   
   SEEN-BY: 266/512 282/1038 291/111 301/1 113 812 305/3 317/3 320/219   
   SEEN-BY: 322/757 335/364 341/66 342/200 396/45 460/58 256 1124 633/280   
   SEEN-BY: 712/848 5020/400 1042 5054/30 5075/35   
   PATH: 153/757 221/6 301/1 460/58 229/426