Historical clue formulations

• Event near the end of a mission — 2015-10-10
• Orbital decay result — 2013-10-06
• Period of radio silence — 2013-01-19
• NASA homecoming — 2007-04-22
• Critical rocket maneuver — 2000-05-14
• NASA concern — 1996-07-20
• Rocket flight event — 1993-12-12