On Sunday May 20th, 2012 a solar eclipse will sweep across east Asia, over the northern Pacific Ocean, and then into the southwestern United States. The eclipse will span from 4:14pm to 6:36pm PST and will be total for 4 minutes and 40 seconds with the maximum eclipse of the sun at 5:30pm PST.
The periodicity and recurrence of solar eclipses is governed by the Saros cycle, a period of approximately 6,585.3 days (18 years 11 days 8 hours). Saros cycle 128 is a solar eclipse that repeats every 18 years and encompasses 73 events. The series started with a partial solar eclipse on August 29, 984 AD and progresses into annular eclipses from August 11, 1561 through July 25, 2120.
In 2012 the eclipse will cover 96.7% of the sun leaving a thin fiery ring of sunlight around the black disc of the moon.