An anonymous reader writes: At this point 47 years ago we had begun our orbit around the Moon," writes Buzz Aldrin in a tweet. Today, Wednesday, July 20th, 2016, marks the 47th anniversary of when NASA astronauts landed on the moon for the very first time. Fox News reports: "Astronauts Neil Armstrong, Buzz Aldrin, and Michael Collins blasted off from Earth on a massive Saturn V rocket on July 16, 1969. Four days later, the Eagle module landed on the surface with Aldrin and Armstrong inside; Collins stayed behind in the orbiting Columbia craft. Millions of people back on Earth watched, captivated, as Armstrong was the first down the ladder, then uttered his now-famous line: 'That's one small step for man, one giant leap for mankind.' The astronauts eventually returned to Earth, splashing down four days later in the Pacific. On the moon, an American flag and a plaque that read, in part, 'We came in peace for all mankind,' remained." To this day, only 12 people have ever walked on the moon. Hopefully, that number will increase within the next decade. NASA is also celebrating the 40th anniversary of the Viking 1 lander's arrival on Mars. Viking 1 was the first American craft to land on the red planet on July 20, 1976.