Unlike the Venus-bound Mariners 1 and 2, Mariners 3 and 4 were intended to head for Mars. Mariner 3 was launched from Cape Canaveral’s Launch Complex 13, on November 5th 1964, but didn’t fare well. There were problems shortly after launch, and the probe’s batteries ran out of power after about 8 hours of flight.
Originally designated Mariner C and D, the two spacecraft of the ‘Mariner Mars 64’ operation were given their numbers, as was traditional, following a successful launch. The plan for Mariner 3 was to rise majestically into the big black, travel for approximately 192 days, using the positions of the Sun and the star Canopus as reference points, then use the brief period while it hurtled past Mars to record data and transmit it back to Earth.
Unfortunately, it seems the solar panels that should have replenished the batteries for the journey to Mars never unfurled, so they only had whatever charge they started the trip with. As a result, Mariner 3 is now up there somewhere, it’s tape recorder unused, in orbit around the Sun.
It's All Going On Up There 