Indonesian Muslims study the Koran with a cleric (top-C) during Ramadan at the Istiqlal mosque in Jakarta on June 23, 2015. More than 1.5 billion Muslims around the world are marking the month, during which believers abstain from eating, drinking, smoking and having sex from dawn until sunset.        AFP PHOTO / ADEK BERRY        (Photo credit should read ADEK BERRY/AFP/Getty Images)