- Captain John Christopher is stationed at the command headquarters of the 498th Air Base in Nebraska, North America. (TOS: "Tomorrow is Yesterday")
- Agents 201 and 347, working undercover on Earth for an unknown alien faction, are killed in a car crash. Three days later, Gary Seven is dispatched to Earth to find out why contact is lost, and after he finds out they are dead, he assumes their mission. (TOS: "Assignment: Earth")
- A major assassination and an Asian coup d'etat occur, both on the same day. (TOS: "Assignment: Earth")
- Also on the same day as the assassination and coup, the United States of America launches an orbital nuclear weapons platform from McKinley Rocket Base. Following the launch, the platform develops a severe malfunction, and begins to reenter the atmosphere. Attempts to initiate destruct initially fail, but the platform eventually detonates 104 miles above Asia. The result is a new and stronger agreement against the use of such weapons. (TOS: "Assignment: Earth")
- The USS Enterprise travels back from 2268 to study how Earth survived this period in its history. It becomes involved in the platform crisis, and is instrumental in causing the detonation of the falling platform. (TOS: "Assignment: Earth")
- According to the Star Trek Encyclopedia (3rd ed., p. 172), Bob Gibson, a St. Louis Cardinals pitcher, wins the first of his two Cy Young Awards.