MSGID: 1:153/757.0 19969a62   
   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 August 20   
        Building in a city are pictured. Above the buildings appears a long   
          dark cylindrical cloud that goes to the horizon. Please see the   
                    explanation for more detailed information.   
      
                            A Roll Cloud Over Wisconsin   
                   Credit: Megan Hanrahan (Pierre cb), Wikipedia   
      
      Explanation: What kind of cloud is this? A type of arcus cloud called a   
      roll cloud. These rare long clouds may form near advancing cold fronts.   
      In particular, a downdraft from an advancing storm front can cause   
      moist warm air to rise, cool below its dew point, and so form a cloud.   
      When this happens uniformly along an extended front, a roll cloud may   
      form. Roll clouds may actually have air circulating along the long   
      horizontal axis of the cloud. A roll cloud is not thought to be able to   
      morph into a tornado. Unlike a similar shelf cloud, a roll cloud is   
      completely detached from their parent cumulonimbus cloud. Pictured   
      here, a roll cloud extends far into the distance as a storm approaches   
      in 2007 in Racine, Wisconsin, USA.   
      
                         Tomorrow's picture: comet unknown   
        __________________________________________________________________   
      
          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: 1/19 123 15/0 16/0 19/10 37 90/1 105/81 106/201 123/130 131   
   SEEN-BY: 129/305 134/100 142/104 153/135 143 757 802 6809 7715 203/0   
   SEEN-BY: 218/700 840 221/1 6 242 360 226/30 227/114 229/110 112 113   
   SEEN-BY: 229/206 307 317 400 426 428 470 664 700 240/5832 266/512   
   SEEN-BY: 280/5003 5006 282/1038 291/111 301/1 317/3 320/119 219 319   
   SEEN-BY: 320/2119 322/0 757 335/364 341/66 342/200 396/45 423/81 460/58   
   SEEN-BY: 633/280 712/848 5020/400 5075/35   
   PATH: 153/757 221/6 1 320/219 229/426