Between 1962 and 1973 the Jet Propulsion Laboratory, which Caltech operates for NASA, designed and built ten probes to visit Mars, Venus and Mercury under the Mariner Program.

Left to right:  Arthur C. Clarke, Ray Bradbury, Walter Sullivan, Carl Sagan, Bruce Murray.
November 12, 1971, Ramo Auditorium, Caltech

In anticipation of Mariner 9’s planned orbit around Mars, Caltech professor of planetary sciences Bruce Murray invited the following gentlemen to participate in a public symposium on “Mars and the Mind of Man”:  the science fiction writers Ray Bradbury and Arthur C. Clarke, Cornell’s Director of the Laboratory for Planetary Studies Carl Sagan, who was a Caltech visiting associate and a member of the Mariner 9 television team along with Murray, and New York Times science editor Walter Sullivan. The symposium was held on November 12, 1971, on the eve of the probe’s planned orbital entry.  Caltech later published a brief account in the January 1972 issue of Engineering and Science .

Sullivan, who served as panel moderator,

Shown above: Walter Sullivan

introduced Sagan,

Shown above: Carl Sagan

who gave a brief history of man’s early fascination with Mars.  Sagan reflected on the 18th century’s belief that Mars was a dying planet.  By the early 20th century, though, thanks to Italian astronomer Giovanni Schiaparelli’s 1877 observations of “canali,” American astronomer Percival Lowell and others believed that intelligent beings had constructed canals.  And early science fiction writers such as Edgar Rice Burroughs further popularized the idea of life on Mars.

Ray Bradbury followed, highlighting Jules Verne and Burroughs’ great influence on his becoming a writer, creating his own stories of human attempts at colonizing the red planet in The Martian Chronicles.

Shown above: Ray Bradbury

In jest, Bradbury said he hoped Mariner 9 photos would find Martians “standing there with huge signs, saying Bradbury was right.”

Shown above: Ray Bradbury

He ended by reciting his poem “If Only We had Taller Been,” summing up why he loves space travel and writes science fiction.  An excerpt from Bradbury’s comments and reading of poem can be viewed in JPL’s memorial video for him .

Next, observing that humans so wanted Mars to be Earthlike—habitable and capable of supporting life—Bruce Murray criticized the earlier misinformation and distortion of scientific observation that he felt had “extended and endured beyond the realm of science to so grab hold of man’s emotions and thoughts” and which had helped mislead the scientific mind as well as the popular mind.

Shown above: Bruce Murray

But, on a more positive note, Murray acknowledged that the Mariner missions were important to the “idea of exploration,” to “learn about something we don’t know.  The fact that we as a people have advanced far enough to explore another planet is something of which we should be very proud.”

Shown above: Arthur C. Clarke

Arthur C. Clarke followed Murray and spoke in defense of science fiction writers as well as those guilty of giving voice to misinformed theories and past misinterpreted observations, pointing out that this had helped to keep the interest in planetary science alive.  He concluded:

“Whatever discoveries are made in the next few days or weeks or months, the frontier of our knowledge is moving inevitably outwards. The frontier is moving on and our viewpoint is changing with it.”

His one and only prediction was that “whether or not there is life on Mars now, there will be by the end of this century.”

Questions and rebuttals followed.  Murray and Sagan debated the possibility of life on Mars, the ways of detecting life if it existed, and whether or not the sterilization of future space vehicles to Mars would be necessary to avoid contamination.

From left to right: Carl Sagan and Bruce Murray

Sagan felt all precautions should be taken and asked Murray to “keep an open mind and see what the [Mariner 9] observations uncover.”  Yet for Murray, observation alone was not enough.  To prove life existed, he felt it would be necessary to examine Martian samples in a lab as had been done with the Apollo moon rocks.  (For more on this, see Caltech and the Apollo Program .)

Ever the positive voice, Bradbury concluded that our curiosity and thirst for knowledge beyond what we know was not foolhardy.  Framing his thoughts as a visionary, Bradbury declared:

Shown above: Ray Bradbury

“I think it’s part of the nature of man to start with romance and build to a reality.  In order to get the facts we have to be excited to go out and get them and there’s only one way to do that—through romance.”

Two years later in 1973, the panel participants published an account of the symposium along with 50 images chosen from over 7,000 taken by Mariner 9.  The book also included “afterthoughts”—their reflections a year later on the discoveries made and the future of human exploration of Mars and beyond.

Shown above: Book cover for Mars and the Mind of Man

Murray admitted having had preconceived prejudices; a year later he was “astonished” at what the Mariner 9 photos and scientific data revealed geologically regarding Mars’ surface.  Yet Murray continued to insist on the need to collect Martian samples to study the planet’s chemical and biological history.

Both Murray and Sagan addressed their concern over the political and socio-economic climate and the ever-decreasing government funding and were curious as to the future of U.S.-Soviet competition and collaboration in space.  Sagan spoke of the value of space exploration to provide a “new perspective on our own planet, its origins, and its possible futures, to see the Earth as it is, one planet among many, a world whose significance is only what we make of it.”

For Clarke, space exploration fulfills the need to explore:

“Whether we find life or not, we will discover things which we could never have imagined.  And these will provide material for the deeper and richer fantasies of the future, just as the earlier observations inspired the fantasies of the past.”

In a similar vein, Sullivan felt that

“the triumph of science and reason over superstition will not be complete until we have pushed our knowledge of the reality of the universe to the limits of our capabilities, both technological and intellectual.

We do know enough already, however, to believe that no myth or legend could be as rich in beauty, wonder, and awe as the full reality of the universe that is our home.”

Bradbury, the last to give his “afterthoughts,” spoke of the significance of science to continually probe and investigate:

“It is the duty of the sciences to break down the barriers between families of knowledge every few years so that we resight, realign, reexperience the miraculous-strange and recombine its components into new families.”

On February 11, 1972, NASA announced that Mariner 9 had achieved all of its goals, but the probe continued to send data until October 27, 1972.

Shown above: Model of Mariner 9

Besides making history as the first spacecraft to successfully orbit another planet, its 7,329 photos mapped 85% of the planet and included images of Mars’ moons Phobos and Deimos.  It gathered data regarding the planet’s surface and atmosphere and detected water vapor over its south pole.  And Mariner 9’s photos were used to help select the landing sites for the two Viking landers that set down on the surface of Mars in 1976.

As for the five gentlemen, in time each was recognized in some fashion for their interest in Mars or planetary science in general:

The American Geophysical Union (AGU) named their “Walter Sullivan Award for Excellence in Science Journalism – Features” after its first honoree who received the award in 1989.

The Minor Planet Center named the asteroid “4923 Clarke” in Arthur C. Clarke’s honor, and the International Astronomical Union named a mountain on Pluto’s moon Charon “Clarke Montes.”

On July 5, 1997, NASA renamed the Mars Pathfinder lander the “Carl Sagan Memorial Station.”

Ray Bradbury was honored on August 22, 2012 when NASA named the Mars Curiosity rover’s landing site “Bradbury Landing.”

And on November 13, 2013, NASA announced two sites on Mars to be named “Murray’s Ridge” and “Murray Buttes” in Bruce Murray’s honor. LK, November 2021