Refer to the passage below and then answer the question afterwards in the same language as the passage:

Passage: The origins of Hurricane John were thought by the United States National Hurricane Center (NHC) to be from a tropical wave that moved off the coast of Africa on July 25, 1994. The wave subsequently moved across the Atlantic Ocean and Caribbean without distinction, before it crossed Central America and moved into the Eastern Pacific Ocean on or around August 8. Upon entering the Eastern Pacific the wave gradually developed, before the NHC initiated advisories on the system and designated it as Tropical Depression Ten-E during August 11. The system was at this time moving westwards and located around 345 miles (555 km) to the south-southeast of Acapulco, Mexico. Quickly developing banding features and well-defined outflow, it was upgraded to a tropical storm and named John later that day.A strong ridge of high pressure over the northeastern Pacific Ocean forced John westward, where upper level wind shear kept John a tropical storm. Intensity fluctuated considerably, however, as shear levels varied. More than once, shear cleared away most of the clouds above John and nearly caused it to weaken to a tropical depression. However, after eight days of slow westward movement across the Pacific Ocean, shear lessened greatly on August 19, and John intensified significantly and was designated as a hurricane at 17:00 PDT. During an eighteen-hour period between August 19 and August 20, John further strengthened from a weak Category 1 hurricane to a Category 3 major hurricane. Around 1100 PDT on August 20, John crossed into the central Pacific, the first of three basin crosses John would make.After entering the central Pacific, John left the area monitored by the NHC and was instead monitored by the Central Pacific Hurricane Center (CPHC). As the storm moved slowly westward, Hurricane John continued to strengthen considerably in an increasingly favorable environment well south of the Hawaiian Islands; on August 22, John was designated a Category 5 hurricane on the Saffir–Simpson hurricane scale (the highest classification...

Question: How close did John make it to Johnston Atoll?
15 miles