When did the following event happen?
Edward Snowden releases classified documents concerning mass surveillance by the NSA.
Select a space in the timeline below.
1957
The world's first artificial satellite, the Sputnik 1, is launched by the Soviet Union.
Note:
BCE means that the date is the number of years before the current era (CE/AD).
c. is short for 'circa' and indicates that the date is considered approximate.