Mariner 6 and 7 spacecraft nearing planet Mars

The twin Mariner 6 and 7 spacecraft are the second pair of Mars missions in NASA's Mariner series of solar system exploration in the 1960s and early 1970s. As with the other Mariners, each launches on an Atlas rocket with either an Agena or Centaur upper-stage booster, and weighs less than half a ton (without onboard rocket propellant). Mariner 7 launches on March 27.