A magnitude 7.3 quake hit Japan’s southern island of Okinawa this Saturday morning, the U.S. Geological Survey reported, and because of that Japan’s weather agency issued a tsunami warning for up to 2 meters. According to USGS, the quake struck at 5:31 a.m. on Saturday (2031 GMT on Friday) 52 miles east of the city of Naha, about 1,600 km (1,000 miles) south of Tokyo.  The earthquake was measured to be at magnitude 6.9 by the...