The Mariner 6 mission, launched on February 1969, was designed
with the use of design plans of earlier flyby probes of the Mariner series. Mariner
6 and 7 comprised a dual-spacecraft
mission to Mars, the sixth and seventh missions in the Mariner series of spacecraft used
for planetary exploration in the flyby mode. This model of the Mariner probe carried
a rocket engine for telemetry corrections, and had continuous telemetry transmission. For
fuel economy this probe was solar powered except for the rocket used in telemetry
corrections. Like the previous Mariner probes, Mariner 6 had no way of attaining a Martian
orbit.
Mariner 6 was an important step in the exploration of Mars, because of the technological innovations involved in its design and in the results of the mission. The technological novelties included in this vehicle were a rocket for trajectory corrections and a new arrangement of equipment. Besides the standard photography equipment, this version of the Mariner series included instruments for planetary experiments housed in seven distinct electronic compartments.
Besides the increased instrumentation and the increased capability for planetary data collection, this new probe had one more innovation with respect to its predecessors. The fully automated on-board computer could be reprogrammed from mission control after the launch. This meant that the mission was more reliable, because modifications could be carried out if necessary. This program feature was not part of the on board computer of previous Mariner missions to Mars. Each of the spacecrafts carried a wide- and narrow-angle television camera, an infrared spectroscope, an infrared radiometer, and an ultraviolet spectroscope. The spacecraft were oriented entirely to planetary data acquisition, and no data were obtained during the trip to Mars or beyond Mars.
The mission was designed to place the probe in a trajectory to fly over the equator and the southern hemisphere of the Red planet. Transmission of images to Earth began only when the probe reached these points, no images were taken before or after the flyby of Mars. The low gain antenna of the probe transmitted the images of both the Martian equator and the Martian southern hemisphere back to Earth. This antenna also helped to provide mission control with constant telemetry of Mariner 6. In addition, he primary objectives and experiments of the missions were to study the surface and atmosphere of Mars during close flybys to establish the basis for future investigations, particularly those relevant to the search for extraterrestrial life, and to demonstrate and develop technologies required for future Mars missions and other long-duration missions far from the Sun. Mariner 6 also had the objective of providing experience and data which would be useful in programming the Mariner 7 encounter 5 days later.
The images and technical innovations of Mariner 6, obtained during the flyby of July 1969, laid the ground work for the Viking Project. Aspects of Mariner 6 such as a reprogramable computer and continuous telemetry were included in the design of the Viking lander and orbiter package. The images obtained by the cameras of this probe were used to select landing sites for the Viking spacecraft.
Each spacecraft carried a wide- and narrow-angle television camera, an infrared spectroscope, an infrared radiometer, and an ultraviolet spectroscope. The spacecraft were oriented entirely to planetary data acquisition, and no data were obtained during the trip to Mars or beyond Mars.