International Satellites for Ionospheric Studies (ISIS) - 2

ISIS 2 was the fourth in a series of Canadian satellites launched to study the ionosphere over one complete solar cycle. ISIS 2 (1971-024A) was launched at 2h53 UTC on April 1, 1971, on a Delta rocket also from the Western test range at Vandenberg AFB in California. On March 13, 1984, ISIS 1, along with ISIS 2, was loaned to Japan's Communications Research Laboratory, which continued to operate the satellites until 1990, when they were shut down due to deterioration of battery capacity.