Space.com cover the subject in depth: "Last-Ever Shuttle Launch Set for July 8, NASA Says"
Partial quote:

The very last space shuttle flight before NASA retires the 30-year program is targeted to launch on July 8, space agency officials announced today.

The shuttle Atlantis is slated to carry four veteran astronauts to the International Space Station to deliver supplies and spare parts for the orbiting outpost. NASA is targeting to launch Atlantis from the Kennedy Space Center in Florida on July 8 at around 11:40 a.m. EDT (1540 GMT).

The target launch date for Atlantis' 12-day mission is based on NASA's current planning. An official launch date will be announced following the mission's Flight Readiness Review on June 28.


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