The shot of JFK's grave also shows the graves of two of his children, Patrick Kennedy only lived for two days in August 1963, and Arabella Kennedy who was stillborn in 1956. Jackie Kennedy Onassis was still living in the 1980s.
The stock footage of the funeral at the end is the state funeral of Unknown Serviceman of the Vietnam Era at Arlington National Cemetery on May 28, 1984.
Technology is shown to have advanced much more quickly in the alternate history than in our timeline. After the funeral Margo is shown using a Nokia 101 phone which in our timeline was not released until 1992.
Showrunner Ronald D. Moore has described the closing episodes of the season as basically being the Cuban missile crisis on the moon.
This is the longest episode of the season, clocking in at 81 minutes.