This is the proof test article of the Viking Mars Lander. For exploration of Mars, Viking represented the culmination of a series of exploratory missions that had begun in 1964 with Mariner 4 and continued with Mariner 6 and Mariner 7 flybys in 1969 and a Mariner 9 orbital mission in 1971 and 1972. The Viking mission used two identical spacecraft, each consisting of a lander and an orbiter. Launched on August 20, 1975 from the Kennedy Space Center in Florida, Viking 1 spent nearly a year cruising to Mars, placed an orbiter in operation around the planet, and landed on July, 20 1976 on the Chryse Planitia (Golden Plains). Viking 2 was launched on September 9, 1975 and landed on September 3, 1976. The Viking project's primary mission ended on November 15, 1976, 11 days before Mars's superior conjunction (its passage behind the sun), although the Viking spacecraft continued to operate for six years after first reaching Mars. The last transmission from the planet reached Earth on November 11, 1982.
While Viking 1 and 2 were on Mars, this third vehicle was used on Earth to simulate their behavior and to test their responses to radio commands. Earlier, it had been used to demonstrate that the landers could survive the stresses they would encounter during the mission.
NASA transferred this artifact to the Museum in 1979.
Transferred from the National Aeronautics and Space Administration
In the 1970s, NASA’s leadership conceived their most daring planetary science expedition, Voyager. It took advantage of a rare astronomical event. Once every 176 years, the giant planets on the outer reaches of the solar system all gather on one side of the sun, and such a configuration was due to occur in the late 1970s. This geometric lineup made possible in a single flight close-up observation of all the planets in the outer solar system (with the exception of Pluto), the “Grand Tour”. This planetary alignment offered a crucial advantage: As the spacecraft passed each planet, gravity would bend its flight path and increase its velocity enough to deliver it to the next destination. Known as “gravity assist,” this complex process gave the spacecraft a “slingshot” boost at each planet. Neptune, the outermost planet in the mission, thus could be reached in 12 rather than 30 years.
To prepare the way for the Grand Tour, in 1964 NASA conceived Pioneer 10 and 11, the first probes to explore the solar system beyond Mars. Severe budgetary constraints hampered the projects, delaying their launch until 1972 and 1973, respectively Pioneer 10 and 11 yielded invaluable science, Designed to last for 30 months, they performed for more than 20 years, returning useful data on Jupiter and Saturn, as well as providing our first look beyond the solar system at interstellar space.
Voyager stood as a greater challenge. A four-planet “grand tour” was theoretically possible. But design was crucial. A single spacecraft might accomplish the mission, but would have to be extraordinarily complex and expensive to travel to the outer reaches of the solar system, endure for more than a decade, and reliably operate a range of scientific instruments. To simplify the mission and limit the expense, the mission relied on two Voyager spacecraft to conduct intensive flyby studies only of Jupiter and Saturn—in effect repeating on a more elaborate scale the flights of the two Pioneers. With an $865 million budget, engineers designed the two Voyagers to conduct as much science and to last as long as possible. Launched from the Kennedy Space Center, Voyager 2 lifted off on August 20, 1977 and Voyager 1 on September 5, 1977, each taking different trajectories to the outer planets.
By December 1980, the two Voyager spacecraft had accomplished successfully their objectives at Jupiter and Saturn. Flybys of the two outermost giant planets, Uranus and Neptune, proved possible—and irresistible—to mission scientists. As the two spacecraft flew across the solar system, scientists re-programmed them via radio communications to aim for the outer planets. Eventually Voyager 1 and Voyager 2 explored all the giant outer planets, including their unique systems of rings and magnetic fields, as well as 48 of their moons.
The two spacecraft returned information to Earth that revolutionized solar system science, helping resolve some key questions while raising intriguing new ones about the origin and evolution of the planets. The two Voyagers took well over 100,000 images of the outer planets, rings, and satellites, as well as millions of magnetic, chemical spectra, and radiation measurements. They discovered rings around Jupiter, volcanoes on Io, shepherding satellites in Saturn’s rings, new moons around Uranus and Neptune, and geysers on Triton. The last imaging sequence was Voyager 1’s portrait of most of the solar system, showing Earth and six other planets as sparks in a dark sky lit by a single bright star, the Sun. In the first decade of the twenty-first century Voyager 1 continued to provide important scientific data about the heliopause, the outer limits of the Sun’s magnetic field and outward flow of the solar wind