Delta II is an American space launch system, originally designed and built by McDonnell Douglas. Delta II is part of the Delta rocket family and entered service in 1989. Delta II vehicles included the Delta 6000, the Delta 7000, and two 7000 variants ("Light" and "Heavy").
After McDonnell Douglas merged with Boeing in 1997, Delta II rockets were built by Boeing Integrated Defense Systems, until Delta rocket production became the responsibility of United Launch Alliance (ULA) on December 1, 2006. ULA now markets Delta II to U.S. government customers, and Boeing Launch Services (BLS) markets Delta II to commercial companies.
Read more about Delta II: History, Vehicle Description, Launch Description, Delta II Launches, Post MLV-3, Comparable Rockets