Delta fans: ever wonder how it all started? Straight from the archives, our new documentary, “A Century of Flight,” is now streaming. Visit http://dl.aero/6183smb1d to see how we became the first U.S. airline to turn 100. | Delta Air Lines

Islands of the Ganges Delta, in Bangladesh, change shape over the years as the Meghna River drains into the Bay of Bengal. Hatiya, the largest island seen at top, is frequently subject to cyclones, monsoons, floods and destructive ocean waves. Despite these risks, islands like these are densely populated; in fact, more than 125 million people live on the Ganges Delta. 22.326515°, 90.993407° Source imagery: Google Timelapse | Daily Overview