Missions Accomplished:  The shuttle Discovery approached from the north of Kennedy Space Center on its finally landing.  I watched from the crest of the new high-span bridge that crosses from Titusville to Merritt Island.  I not only heard the twin sonic booms unmuffled by the water but they echoed off the nearby buildings.  The shuttle passed through a thin white cumulus, dropped its landing gear and floated downward until it was blurred by the mid day haze and swallowed by the mangroves in the wildlife refuge.  Discovery successfully touched down at 11:57 a.m EST on March 9, 2011.  After thirty-nine missions the most traveled spacecraft is now retired.