July-August 1982:the Voyager Mars project

The Voyager programme began in 1960 as a planning objective of the Jet Propulsion Laboratory. Biological studies played a key role; the lander was to be equipped with an Automated Biological Laboratory that would look for energy transfer and conversion, macro-molecules, reproduction and growth, substances associated with Earth life and evidence of molecular organisation. In 1964, the space science board of the National Academy of Sciences stated that life on Mars was possible and that a high priority programme should be established to study it. Others were not so sure. Dr. Barry Commoner, from Washington University, said at a meeting of the American Association for the Advancement of Science that because there was no liquid water on Mars, there was no reasonable chance of life and therefore no need to go looking for it. He accused the board of over-rating the possibility. NASA responded by saying that life was at least possible so that the emphasis was on biology.

Technical Features and Re-orientation

Voyager was to be a three part spacecraft launched by Saturn lB/Centaur. The spacecraft bus carried the solar panels, the radio dish and the experiment package. Weight was to be approximately 1,800 lbs (816 kg). The retro-propulsion system contained the rockets arid fuel tanks for attitude control, mid-course correction and Mars orbiting insertion. The unit weighed between 2,200 and 4,400 lbs (998 to 1,995 kg). The third part was the capsule/lander; shaped like the Apollo Command Module, and its weight ranged from 1,000 to 6,000 lbs (454 to 2,722 kg) depending on the specific mission. After the heating phase of atmospheric entry, the lander would separate and be lowered to the surface by parachute. Two Voyagers were to be launched during every Mars launch window from 1969 to 1977, each more complicated than the last. Total cost of the programme would be $1,000 million.

On 14 July 1965, Mariner 4 flew past Mars, sending back results that were devastating to Voyager. The capsule design was based on a 10 or 11 millibar pressure at Mars’ surface but when the atmospheric data was analysed, it indicated only 5 to 7 millibars - too low for parachutes to be used all the way to the surface. This meant a retro-system would have to be included on the lander and the atmospheric entry path would have to be more shallow.

By the end of 1965, Voyager had entered a two year period of re-designing. Unspent funding was redirected to revitalise the Mariner programme. This provided for a mission to Venus in 1967, a dual fly-by of Mars in 1969 and, in 1971, two Mars orbiters.

The New Voyager

The post-Mariner 4 Voyager was about triple the weight of the earlier version. It still, however, retained the three part construction. The capsule’s shape was flatter, more disc-like. Total capsule/lander weight was about 5,000 lbs (2,268 kg); later mission weights could go to 7,000 lbs (3,175 kg). Unlike the earlier version, the capsule would remain attached to the bus when it entered orbit. The lander would weigh 860 to 1,500 lbs (390 to 680 kg) and was similar in design to the Surveyor Moon lander. The bus weighed 2,500 lbs (1,134 kg) empty and the greatest increase was in the retro-propulsion system. It now weighed 13,000 to 15,000 lbs (5,896 to 6.803 kg) due to the capsule being retained in orbit. Total weight would be 20,500 to 24,500 lbs (9,298 to 11,113 kg). A pair of Voyagers would be launched aboard a single Saturn 5 in missions flown in 1973, 1975, 1977 and 1979. Total programme cost had climbed to $2,400 million; money was becoming a central issue for Voyager.

In early March 1966, the House Space Science and Applications sub-committee issued its recommendations on the NASA budget. It urged that Congress take a larger role in determining the scope and direction of the space programme. It proposed that Mariner Venus 67 be cancelled and the $42 million be used to speed up the exploration of Mars. $20 million would be added to the Mariner Mars 69 project and $22 million to the $10 million Voyager request. When the NASA budget for 1966 was finally approved that summer, the 1967 Venus mission had survived and $13 million was added to Voyager.

When the Voyager budget came up for Congressional action in 1967, it faced a far different reception. In the six years since President Kennedy had launched America toward the Moon, much had changed. The cold war had faded, Kennedy was dead, the Vietnam War was stirring protest marches and cities were torn by race riots. That January the Apollo fire had killed Grissom, White and Chaffee. Under such conditions, the NASA budget made a tempting target. The Voyager request totalled $71.5 million.

When the NASA budget emerged from the House and Senate space committees, it had undergone major cuts. Mariner Mars 71, Sunblazer, the Commercial Broadcast Satellite, the large solid fuel rocket programme, the Electronic Research Center, Apollo Application Program and Voyager had all been hit. The House committee had reduced the Voyager authorization to $50 million and the Senate committee had eliminated it entirely. On the floor of the Congress, the debate was set in terms of health care, food and the city problems versus space. The differing House and Senate bills had to be reconciled in committee and Voyager was one area of contention. The House members wanted funding restored, while Senate members were willing to provide some funding to Voyager if the House would agree to larger cuts in the Apollo Applications Program in. Voyager emerged with $42 million.

On 18 August 1967, the House eliminated all funding for Voyager. The NASA authorization bill had been cut by $516 million, meaning that the US space programme had been reduced to Apollo only. The AAP programme was limited in scope and the planetary programme curtailed severely. Beyond the mid-1970’s, there were no authorised programmes. To keep Mars exploration alive, NASA could propose that Voyager be delayed until 1975 or a small orbiter/lander could be developed for launch by a Titan III Centaur. The first option was not realistic and the other ran the risk of irritating Congress after it had cut a planetary programme. However, the second option was selected, ultimately to become Viking.