We live in an age with little patience for history. I was frequently reminded of that in the first few days after our successful landing on Mars. Continually I was asked, "What are your thoughts as you look at these pictures?" What were my thoughts? A kaleidoscope of memories eight years of planning, moments of frustration, friendships forged by common problems, and now everything happening just as we had disbelievingly promised each other it would.
The first few times I was asked about my thoughts I tried to describe those eight years embedded in the first picture. And that was when I discovered that history was not the subject of the hour. Quickly enough I learned to give the desired response, a crisp geologic description sprinkled with superlatives, sized to fit a 30 sec spot on tomorrow's news program. But I continue to think about the history. If you want to appreciate these pictures fully, you have to travel with us as the Viking Project is transformed slowly and painfully from an idea to a durable spacecraft, propelled on its long journey to Mars.
The Viking Mission was first defined by NASA in 1968. Its predecessor, Voyager, never passed beyond the talking stage. Starting in 1965 and continuing through 1967, tentative plans had been developed for an integrated long term program of martian exploration involving, first, flyby and orbiter missions, and then a series of lander missions in 1973, 1975, and 1977. Each of these Voyager Landers was to be launched by a giant Saturn V rocket. Successive missions were to contain increasingly sophisticated scientific equipment, culminating in a 90 to 450 kg biological laboratory in the 1977 Voyager spacecraft. Conjured up during the heyday of Apollo when unlimited budgets were projected far into the future, the ambitious Voyager program was a victim of general economic retrenchment in the late 1960s. In its stead a very small "hard lander" was briefly considered. In one design a protective balsawood shell broke open on impact, revealing a squat watermelon sized spacecraft. A camera was positioned on an extendable mast. Little else in the way of scientific equipment was included. It was recognized that the mission lacked both scientific merit and exploratory excitement. It was replaced by the more ambitious Viking which, ironically, grew to a point where it incorporated many of the capabilities originally included in Voyager.
Viking included two Orbiter Lander pairs to be placed into orbit about Mars. Following successful orbit insertion the Landers would be released and directed toward the surface. Slowed first by aerodynamic drag, then by parachute, and finally by retrorockets, they were designed for a "soft" landing. At 2.5 m sec the jolt would be something like that encountered when jumping off a 35 cm high stool on Earth. Except for the parachute phase, the entire sequence would be similar to that employed for Apollo landings on the Moon (fig. 1).
Exactly how is a decision made to fly a particular mission? NASA administrators have at their disposal a number of planning teams, staffed primarily by engineers and cost analysts. In addition, advisory committees of scientists are asked to analyze and put in sequence the various mission options. Building on this background, NASA administrators submit a specific budget with a particular mission called out by name, something termed a "line item." If the mission survives subsequent budget trimming by the Office of Management and Budget and Congress, it is elevated to an "approved" category. Various aerospace companies are invited to submit bids for the construction of the spacecraft, following the design requirements established by NASA engineers. At the same time an "Announcement of Flight Opportunity" is widely circulated among universities and research laboratories. Scientists wishing to propose a scientific experiment of their own choosing, or to participate in an experiment already slated for inclusion-a camera would be a good example-send in their credentials. A disinterested group of scientists meets to consider all applications, and then to recommend to NASA those considered best qualified.
It is a supremely democratic arrangement. Everyone can respond to the opportunity. In my own case, for several years I had been involved peripherally in mapping the Moon, using photographic information from Lunar Orbiter missions. I wanted to become more closely involved with space science, but was advised by a NASA official that there was no middle ground. Either you were a dilettante or you were an approved mission investigator. It so happened, he added, that the deadline for Viking applications was only several weeks away. Armed with little additional information, I obtained the necessary forms and started filling them out. Midway through I was tempted to chuck the whole venture. A series of questions seemed aimed specifically at revealing my inadequacies. What was my previous research on Mars? Zero. List my relevant publications. Pretty meager. List the institutional resources that would support my efforts. None. Against my better judgement I persevered, and filed the completed application.
Several months later, having heard nothing and wishing to end the whole  debacle, I called NASA. To my amazement, my name was recognized, and a man told me that official announcements would be made in a few days. Conservative and skeptical though I am, I sensed that this reception hinted at good news. Sure enough, my application was approved.
The initial Lander Imaging Planning Team also included Alan Binder, an astronomer then at the IIT Research Institute; Elliott Levinthal, a physicist at Stanford University; Elliot Morris, a geologist with the U.S. Geological Survey; and Carl Sagan, an astronomer exobiologist at Cornell University. Subsequently, the team was enlarged to include Fred Huck, a research engineer at NASA Langley Research Center; Sid Liebes, a physicist at Stanford University; Jim Pollack , a physicist astronomer at NASA Ames Research Center; and Andy Young, an astronomer at Texas A&M University. We profited enormously from the counsel of Bill Patterson, Brown University, who served as team engineer, and Glenn Taylor, an engineer administrator who supervised the development of the cameras in behalf of the Langley Research Center and served as liaison between our team and the rest of the Viking Project.
My first person to person contact with Viking came when Gerry Soffen, Project Scientist, and Tom Young, Science Integration Manager, journeyed to Providence in the fall of 1968. The stated purpose was to explore a possibility that I would become leader of the Lander Imaging Planning Science Team. Basically, I suspect they were curious to meet someone they knew only by name. I recall that we had a pleasant lunch. There was excited talk about all that lay ahead. But we had no way of anticipating that it was the start of a professional alliance and personal friendship that would stretch forward, day after day, for eight years.
All early planning was conducted at the Langley Research Center in Hampton, Virginia. Our first task was to meet there, all the scientists recently selected some 60 in number and the engineers who had been considering the design of the mission for almost a year. During the meeting we heard extravagant promises regarding the scientific possibilities of Viking. It was heady fare.