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On Mars: Exploration of the Red Planet. 1958-1978



ATTRACTIVE TARGET FOR EXPLORATION


[2] Discussion of interplanetary travel did not have a technological foundation until after World War II, when liquid-fueled rockets began to show promise as a transportation system. Once rockets reached escape velocities, scientists began proposing experiments for them to carry, and Mars was an early target for interplanetary travel.
Mars fell into that class of stars the Greeks called planetes, or "wanderers." Not only did it move, but upon close observation it appeared to move irregularly. The early Greek astronomer Hipparchus (160-125 B.C.) recognized that Mars did not always move from west to east when seen against the constellations of fixed stars. Occasionally, the planet moved in the opposite direction. This phenomenon perplexed all astronomers who believed Earth to be the center of the universe, and it was not until Johannes Kepler provided a mathematical explanation for the Copernican conclusion that early scientists realized that Earth, too, was a wanderer. The apparent motion of Mars was then seen to be a consequence of the relative motions of the two planets. By the time Kepler published Astronomia nova (New astronomy), subtitled De motibus stellae Martis (On the motion of Mars), in 1609, Galileo was preparing his first report on his observations with the telescope-Sidereus nuncius (Messenger of the stars), 1610. (See Bibliographic Essay for a bibliography of basic materials related to Mars published through 1958.)
From 1659, when Christiaan Huyghens made the first telescopic drawing of Mars to show a definite surface feature, the planet has fascinated observers because its surface appears to change. The polar caps wax and wane. Under close scrutiny with powerful telescopes, astronomers watch Mars darken with a periodicity that parallels seasonal changes. In the 1870s and l880s during Martian oppositions with Earth,^* Giovanni Virginio Schiaparelli, director of the observatory at Milan, saw a network of fine lines on the planet's surface. These canali , Italian for channels or grooves, quickly became canals in the popular and scientific media. Canals would be....



[3] (The apparent motion of Mars. When Earth and Mars are close to opposition, Mars, viewed from Earth, appears to reverse its motion relative to fixed stars. Above, the simultaneous positions of Earth and Mars are shown in their orbits around the sun at successive times. The apparent position of Mars as seen from Earth is the point where the line passing through the position of both appears to intersect the background of fixed stars. These points are represented at the right. Below are shown the locations of Mars in the sky before and after the 1965 opposition. Samuel Glasstone, The Book of Mars, NASA SP-179 (1968).



....evidence of intelligent life on Mars. The French astronomer Camille Flammarion published in 1892 a 608-page compilation of his observations under the provocative title La Planete Mars, et ses conditions d'habitabilité (The planet Mars and its conditions of habitability). In America, Percival Lowell, in an 1895 volume titled simply Mars , took the leap and postulated that an intelligent race of Martians had unified politically to build irrigation canals to transport their dwindling water supply. Acting cooperatively, the beings on Mars were battling bravely against the progressive desiccation of an aging world. Thus created, the Martians grew and prospered, assisted by that popular genre science fiction. Percy Greg's hero in Across the Zodiac made probably the first interplanetary trip to Mars in 1880 in a spaceship equipped with a hydroponic system and walls nearly a meter thick. Other early travelers followed him into the solar system in A Plunge into Space (l890) by Robert Cromie, A Journey to Other Worlds (1894) by John Jacob Astor, Auf zwei Planeten (On two planets, 1897) by....




[4] (These drawing of Mars by Francesco Fontana were the first done by an astronomer using a telescope. Willy Ley commented, "Unfortunately, Fontana's telescope must have been a very poor instrument, for the Martian features which appear in his drawings-the darkish circle and the dark central spot which he called 'a very black pill'-obviously originated inside his telescope." The drawing at left was made in 1636, the one at right on 24 August 1638. Wernher von Braun and Willy Ley, The Exploration of Mars (New York, Viking Press, 1956); Camille Flammarion, La Planete Mars et ses conditions d'habitabilité (1982).



....Kurd Lasswitz, H. G. Wells's well-known War of the Worlds (1898) ¹, and astronomer Garrett P. Serviss's Edison's Conquest of Mars (1898). In "Intelligence on Mars" (1896), Wells discussed his theories on the origins and evolution of life there, concluding, "No phase of anthropomorphism is more naive than the supposition of men on Mars." ² Scientists and novelists alike, however, continued to consider the ability of Mars to support life in some form.
Until the l950s, investigations of Mars were limited to what scientists could observe through telescopes, but this did not stop their dreaming of a trip through space to visit the planets firsthand. Willy Ley in The Conquest of Space determined to awaken public interest in space adventure in the....




(Christiaan Huyghen's first drawing of Mars (at left below), dated 28 November, 1659, shows surface features he observed through his telescope. Of two later sketches, one of the planet as observed on 13 August 1672 at 10:30 a.m. (center below) shows the polar cap. At right below is Mars as observed on 17 May 1683 at 10:30 a.m. Flammarion, La Planète Mars.)







[5] (Nathaniel E. Green observed changes in the southern Martian polar cap during opposition. The first sketch, at top, shows the polar cap on 1 September 1877, and the second, the cap seven days later. Flammarion, La Planète Mars.)



....postwar era. His book was an updated primer to spaceflight that reflected Germany's wartime developments in rocketry. Ley even took his readers on a voyage to the moon. Considering the planets, be noted, "More has been written about Mars than about any other planet, more than about all the other planets together," because Mars was indeed "something to think about and something to be interested in." Alfred Russel Wallace's devastating critique (1907) of Percival Lowell's theories about life and canals did not alter Ley's belief in life on that planet. "As of 1949: the canals on Mars do exist," Ley said. "What they are will not be decided until astronomy has entered its next era" (meaning manned exploration). ³ Ley's long-time friend and fellow proponent of interplanetary travel, Wernher von Braun, presented one of the earliest technical discussions describing how Earthlings might travel to Mars. During the "desert years"....




[Whole page 6] (Giovanni Schiaparelli's map of Mars, compiled over the period 1877-1886, used names based on classical geography or were simply descriptive terms; for example, Mare australe (Southern Sea). Most of these place names are still in use today. Flammarion, La Planète Mars.)



[7]....of the late 1940s when he and his fellow specialists from the German rocket program worked for the U.S. Army at Fort Bliss, Texas, and White Sands Providing Ground, New Mexico, testing improved versions of the V-2 missile, von Braun wrote a lengthy essay outlinings a manned Mars exploration program. Published first in 1952 as "Das Marsprojekt; Studie einer interplanetarischen Expedition" in a special issue of the journal Weltraumfahrt, von Braun's ideas were made available in America the following year. ⁴

Believing that nearly anything was technologically possible given adequate resources and enthusiasm, von Braun noted in The Mars Project that the mission he proposed would be large and expensive, "but neither the scale nor the expense would seem out of proportion to the capabilities of the expedition or to the results anticipated.'' Von Braun thought it was feasible to consider reaching Mars using conventional chemical propellants, nitric acid and hydrazine. One of his major fears was that spaceflight would be delayed until more advanced fuels became available, and he was reluctant to wait for cryogenic propellants or nuclear propulsion systems to be developed. He believed that existing technology was sufficient to build the launch vehicles and spacecraft needed for a voyage to Mars in his lifetime.
According to von Braun's early proposal, "a flotilla of ten space vessels manned by not less than 70 men" would be necessary for the expedition. Each ship would be assembled in Earth orbit from materials shuttled there by special ferry craft. This ferrying operation would last eight months and require 950 flights. The flight plan called for an elliptical orbit around the sun. At the point where that ellipse was tangent to the path of Mars, the spacecraft would be attracted to the planet by its gravitational field. Von Braun proposed to attach wings to three of the ships while they were in Mars orbit so they could make glider entries into the thin Martian atmosphere.^**
The three landers would be capable of placing a payload of 149 metric tons on the planet, including "rations, vehicles, inflatable rubber housing, combustibles, motor fuels, research equipment, and the like.'' Since the ships would land in uncharted regions, the first ship would be equipped with skis or runners so that it could land on the smooth surfaces of the frost-covered polar regions. With tractors and trailers equipped with caterpillar tracks, "the crew of the first landing boat would proceed to the Martian equator [5000 kilometers away] and there....prepare a suitable strip for the wheeled landing gears of the remaining two boats." After 400 days of reconnaissance, the 50-man landing party would return to the seven vessels orbiting Mars and journey back to Earth. ⁵
One item missing from von Braun's Mars voyage was a launch date. While he concluded that such venture was possible, he did not say when he [8] expected it to take place. A launch vehicle specialist, von Braun was more concerned with the development of basic flight capability and techniques that could be adapted subsequently for flights to the moon or the planets. "For any expedition to be successful, it is essential that the first phase of space travel, the development of a reliable ferry vessel which can carry personnel into [Earth orbit], be successfully completed." ⁶ Thus, von Braun's flight to Mars would begin with the building of reusable launch vehicles and orbiting space stations. He and his fellow spaceflight promoters discussed such a program at the first annual symposium on space travel held at the Hayden Planetarium in October 1951, in a series of articles in Collier's in March 1952, and in Across the Space Frontier, a book published in 1952. ⁷ Two years later, however, von Braun concluded publicly that a major manned voyage to Mars was a project for the more distant future. As pointed out in an article entitled "Can We Get to Mars?"
: The difficulties of a trip to Mars are formidable. The outbound journey, following a huge arc [568 million kilometers], will take eight months-even with rocket ships that travel many thousands of miles per hour. For more than a year, the explorers will have to live on the great red planet, waiting for it to swing into a favorable position for the return trip. Another eight months will pass before the 70 members of the pioneer expedition set foot on earth again. ⁸

Von Braun feared that it might "be a century or more'' before man was ready to explore Mars. ⁹
But five years later von Braun's response loan inquiry from the House Select Committee on Astronautics and Space Exploration indicated that his thinking had changed again. Gathering ideas for possible space activities, the House committee solicited opinions from the aerospace community and published its findings in The Next Ten Years in Space, 1959-1969. Von Braun considered "manned flight around the Moon....possible within the next 8 to 10 years, and a 2-way flight to the Moon, including landing, a few years thereafter.'' He believed it "unlikely that either Soviet or American technology will be far enough advanced in the next 10 years to permit man's reaching the planets, although instrumented probes to the nearer planets (Mars or Venus) are a certainty." ¹⁰
A number of important technological and political events were instrumental in changing the rocket expert's thinking about American goals for space. Rocket technology had advanced considerably, as evidenced in the development of both American and Soviet intercontinental ballistic missiles. Soviet progress was forcefully impressed on the American consciousness by the orbital flights of Sputnik 1 and Sputnik 2 in the fall of 1957. Even as the Soviet Union stole a march on the Americans, von Braun and many others were busy defining and planning appropriate space projects for the United States.
[9] Von Braun and his colleagues at the Army Ballistic Missile Agency in Huntsville, Alabama, has lost out to the Navy in September 1955 in the competition to launch an Earth satellite and had failed in their bid against the Air Force in November 1956 to be responsible for the development of intermediate range ballistic missiles. These setbacks prompted the managers of the agency to seek new justifications for the large launch vehicles they wanted to develop. Creating boosters thar could be used for space exploration was the obvious answer. This goal was consistent with von Braun's long-time wish to see spaceflight a reality. In April 1957, Army Ballistic Missile Agency planners began to review United States missile programs in the light of known Soviet spaceflight capabilities and proposed a development strategy. The first edition of their sales pitch, "A National Integrated Missile and Space Vehicle Development Program," was issued on 10 December 1957. It reflected the post-Sputnik crisis:
: The need for an integrated missile and space program within the United Sites is accentuated by the recent Soviet satellite accomplishments and the resulting psychological intimidation of the West�we are bordering on the era of space travel....A review and revision of our scientific and military efforts planned for the next ten years will insure that provisions for space exploration and warfare are incorporated into the overall development program. ¹¹

The National Advisory Committee for Aeronautics (NACA) was also moving quickly in the wake of Sputnik. In an effort to define its role in the dawning space age, NACA's Committee on Aerodynamics resolved in November 1957 that the agency would embark upon "an aggressive program....for increased NACA participation in upper atmosphere space flight research." Subsequently, a Special Committee on Space Research under the direction of H. Guyford Stever, a physicist and dean at the Massachusetts Institute of Technology, was established "to survey the whole problem of space technology from the point of view of needed research and development and advise the National Advisory Committee for Aeronautics with respect to actions which the NACA should take." ¹²
On 18 July 1958, the Working Group on Vehicular Program^*** of the Stever committee presented to NACA a revised edition of the Huntsville report on missile and space vehicle development. That document proposed an expanded list of possible goals for the American space program based on a phased approach to the development of successively more powerful launch vehicles. Those vehicles were divided into five generations:
: First Generation-Based on SRBM boosters [short range]; Second Generation-Based on IRBM boosters [intermediate range]; [10] Third Generation-Based on ICBM boosters [intercontinental]; Fourth Generation- Based on 1.5. million-pound-thrust [6.8-million-newton] boosters; Fifth Generation-Based on 3 to 5 million-pound-thrust [13-to-22-newton] boosters. ¹³
The planets, of course, were desirable targets for space exploration, but the realities of the emerging space race with the Soviet Union made the moon a more attractive goal politically for the late 1960s. In 1958, Stever's group did not think it would be possible to send a 2250-kilogram probe to Mars for at least a decade: it would be that long before the fourth-generation launch vehicle necessary for such a payload was ready. A manned mission to Mars or Venus was not projected to occur before 1977.
Implicit in the working group's timetable (table l ) was a gradual approach to space exploration. The proposed program was still ambitious, but it was increasingly apparent that scientific investigations in space would have to await new launch vehicles tailored to specific projects. It was technologically feasible to go to the moon and the planets, but the translation of feasibility into reality would require a national program and a new government agency to manage such activities. ¹⁴

Table 1 [11]
Milestones of the Recommended U.S. Spaceflight Program, July 1958

Item	Date	Event	Vehicle Generation
1	Jan. 1958	First 20-lb [9-kg] satellite (ABMA/JPL)	I
2	Aug. 1958	First 30-lb [14-kg] lunar probe (Douglas/RW/Aerojet)	II
3	Nov. 1958	First recoverable 300-lb [140-kg] satellite (Douglas/Bell/Lockheed)	II
4	May 1959	First 1500-lb [680-kg] satellite	II
5	Jun. 1959	First powered flight with X-15
6	Jul. 1959	First recoverable 2100-lb [950-kg] satellite	II and/or III
7	Nov. 1959	First 400-lb [180-kg] lunar probe	II and/or III
8	Dec. 1959	First 100-lb [45-kg] lunar soft landing	II and/or III
9	Jan. 1960	First 300-lb [135-kg] lunar satellite	II and/or III
10	Jul. 1960	First wingless manned orbital return flight	II and/or III
11	Dec. 1960	First 10 000-lb [4500-kg] orbital capability	III
12	Feb. 1961	First 2800/600-lb [1300/270] lunar hard or soft landing	III
13	Apr. 1961	First 2500-lb [1100-kg] planetary or solar probe	III
14	Sept.1961	First flight with 1.5-million-lb [6.7-million-newton] thrust	IV
15	Aug. 1962	First winged orbital return flight	III
16	Nov. 1962	Four-man experimental space station	III
17	Jan. 1963	First 30 000-lb [13 800-kg] orbital capability	IV
18	Feb. 1963	First 3500-lb [1590-kg] unmanned lunar circumnavigation and return	IV
19	Apr. 1963	First 5500-lb [2500-kg] soft lunar landing	IV
20	Jul.1964	First 3500-lb [1590-kg] manned lunar circumnavigation and return	IV
21	Sept. 1964	Establishment of a 20-man space station	IV
22	Jul. 1965	Final assembly of first 1000-ton [900-metric-ton] lunar landing vehicle (emergency manned lunar landing capability)	IV
23	Aug. 1966	Final assembly of second 1000-ton [900-metric-ton] landing vehicle and first expedition to moon	IV
24	Jan. 1967	First 5000-lb [2300-kg] Martian probe	IV
25	May 1967	First 5000-lb [2300-kg] Venus probe	IV
26	Sept. 1967	Completion of 50-man, 500-ton [450-metric-ton] permanent space station	IV
27	1972	Large scientific moon expedition	V
28	1973/1974	Establishment of permanent moon base	V
29	1977	First manned expedition to a planet	V
30	1980	Second manned expedition to a planet	V

Source: NACA, Special Committee on Space Technology, Working Group on Vehicular Program, "A National Integrated Missile and Space Vehicle Development Program," 18 July 1958, p. 6.

* Appendix A describes some of the orbital relationships between Earth and Mars.
** Earth's atmospheric pressure at sea level is 1013 millibars. From calculations made by A. Dollfus of the Paris Observatory in the 1950s, the mean Martian atmospheric pressure was determined to be about 85 millibars. The actual figure as detrmined by viking measurements is 75 millibars.
*** Members of the Working Group on Vehicular Program were W. von Braun, Chairman; S. K. Hoffman; N. C. Appold; A. Hyatt; L. N. Ridenour; A. Silverstein; K. A. Ehricke; M. W. Hunter; C. C. Ross; H. J. Stewart; G. S. Trimble, Jr.; and W. H. Woodward, Secretary.