Fifty years ago today, Apollo 9, over the Pacific near the end of its 151st orbit, fired its big engine, the Service Propulsion System, for the eighth and final time.  The 11.74-second burn nudged the spacecraft out of orbit after a mission of tens days.

Apollo 9, the first test of the Lunar Module (LM) with a crew aboard, marked a major milestone in Apollo’s history.  Yet the accelerating pace of the moon program had already left the flight behind.   The crew to attempt the first landing, Neil Armstrong, Mike Collins and Buzz Aldrin was in training.   The vehicle for the next mission, Apollo 10, a final test of the Lunar Module, rolled to the pad two days ago for a flight in mid-May.  Nothing now stood in the way of its mission, to fly the LM in lunar orbit in a dress rehearsal for the next mission just two months later.  And the day and exact time, if Apollo 10 went well, for Apollo 11’s landing was set:  2:19 p.m. on July 20.

At 12:01 p.m. EST, under its three parachutes, Apollo 9 splashed down just a mile from target and within sight of the recovery ship, the USS Guadalcanal.   President Richard Nixon said, “The epic flight of Apollo 9 will be recorded in history as ten days that thrilled the world.”   And like Apollo 7, the program’s other Earth-orbital mission, almost before it had jettisoned its parachutes, it was forgotten.