Voyage to the Morning Star

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The bone-weary scientists had worked all night. But as they walked away from the lab, they seemed curiously reluctant to quit. They loitered in the cool dawn and stared at the eastern horizon. There, the pale glow of Venus marked the morning--as it has done so many times since man learned to recognize Earth's nearest planetary neighbor.

On that December day, though, the morning star held a special attraction for the men of Caltech's Jet Propulsion Laboratory. Almost as if they could see it all happening, they squinted into 36 million miles of space, out into the vicinity of Venus, where for the first time in history a man-made space traveler was cruising into range. A gold and gleaming machine, sporting angular purple wings and unblinking electronic eyes, was swooping toward its target. Mariner II was giving earthbound scientists their first close look at the distant planet that has tugged so long at their adventurous imagination. And when Mariner's radioed reports were finally decoded by the JPL crew that had built the spacecraft and sent it on its way, Venus would never seem quite the same again.

Would the morning star live up to the romance of science and turn out to be teeming with life? Were there, as some romanticists confidently expected, forests of intelligent, moving trees? Or would Mariner prove the accuracy of some of the glummer theories of radio astronomy --that Venus is a barren ball covered with a dull layer of dust? Last week JPL's boss, New Zealand-born Physicist William Hayward Pickering, brought his Mariner team to Washington to deliver a batch of decoded data containing the first series of answers.

They were not calculated to delight space fictioneers. Although such respected astronomers as Harvard's Harlow Shapley and Britain's Sir Bernard Lovell have speculated that there may be hundreds of millions of heavenly bodies capable of supporting life, Mariner's sensitive instruments testified that Venus does not rate a place on the long list. It appears to be hot and dry and dead. If there is any life at all--a doubtful possibility at best--it must float as dustlike microorganisms in comparatively cool clouds.

Scientists are still puzzling over Mariner's findings, but on one point they are in unanimous agreement. The very fact that Mariner carried its intricate cargo so far, made so many observations and radioed its reports to earth with such singular success marks the most important accomplishment in the annals of space exploration. It is a proud first for the U.S. No achievement by Russian cosmonaut or U.S. astronaut, no experiment made by any of the myriad other satellites that have been shot aloft has taught man nearly so much as he has learned already from the improbable voyage of Mariner II.

New Life. Only a few years ago, any meaningful voyage to Venus would have been impossible. Spacemanship of such a high order involves the creation of clever mechanical beasts that can live and function for months in a hostile environment beyond Earth's atmosphere. They must obey commands from millions of miles away, a requirement that calls for radio techniques of incredible delicacy. Giant computers, only recently developed, must plot celestial courses, and enormous vacuum chambers are needed to test behavior in simulated space. These strange space creatures are almost a new type of life, comparable in zoological terms to the first venturesome animals that crawled out of sea water and learned to live in air and sunlight. To breed them calls for the talents of many branches of science.

An unmanned spacecraft such as Mariner must be designed, as a human baby, to cope successively with three different environments. First it must face life on Earth, snuggled by gentle gravitation and sheltered by the atmosphere. So careful are its guardians to keep it clean and uncontaminated, they even dress like medical men and work in an antiseptic, hospital-like atmosphere. While the spacecraft resists corrosion from water vapor and the sea-salted air of Cape Canaveral, anxious humans are always around to protect it; it gets what energy it needs through a bundle of wires called an umbilical cable. This sheltered period is comparable to a baby's gestation in its mother's womb.

Then comes the crisis of launching. For a few violent minutes, the spacecraft, folded into the nose of its boost vehicle, must withstand an enormous increase of gravity due to acceleration. It is shaken by fierce vibration as heat sears through the shroud that protects it from racing air. Many spacecraft have died during launch, just as human babies sometimes die during delivery.

When the spacecraft passes beyond Earth's atmosphere, its real life begins. The shroud around it falls away; there is no air now to do damage. Gravity has fallen to zero, and frail antennae and solar panels can swing outward, pushed by feeble springs. The spacecraft absorbs sunlight, as a baby breathes air, and electrical energy pulses through its metal circulatory system. It is now a denizen of space.

Heat Balance. Once Mariner was safely on its way, Physicist Pickering and his JPL teammates watched over their creation like anxious parents. There was so much that could go wrong. Materials that are well behaved in the atmosphere may be useless in space. Even some metals turn to vapor and must be used with caution. Another peril is heat. Space itself has no temperature (having no matter that can be hot or cold), but each object in space assumes a temperature that depends on the balance between the radiation that it absorbs and the radiation that it emits. A dab of paint (if it stays in place) can spell the difference between cold and hot. So can a shiny part that reflects sunlight to a light-absorbent part. Keeping all parts at proper temperatures is one of the hardest jobs in designing a viable spacecraft.

As radio signals came back from the far-voyaging craft in a complicated code that seemed a gibberish of meaningless letters and symbols, Pickering and his crew studied and restudied the data the signals contained. Always the scientists were alert for signs of trouble. For three and a half months, as Mariner curved on its finely calculated course, the acid of worry corroded the most placid temperaments. "Nearly every night," says one veteran of those long watches in JPL's Space Flight Operations Center, "I had a dream that the earth sensor was heating at a rate of 60DEG an hour. And I awoke each morning with a 60DEG-per-hour sweat."

The triumph that JPL celebrated on the morning of Dec. 14, 1962 was truly a double one. Not only had Mariner successfully completed its journey, but its creators, too, had managed to survive the strains of the trip.

But all the frantic concentration of energy as Mariner completed the longest and most complex adventure ever successfully completed by any man-made object could not obscure the years of effort that stretched back to a time before Mariner was even conceived. The incredible voyage really began in 1936, when six Caltech students and some faculty scientists hiked up the Arroyo Seco, a dry gulch in the mountains back of Pasadena, and searched out a secluded spot from which to fire their primitive rockets.

Only stubborn enthusiasm kept their ill-financed experiments alive until the start of World War II. Then the Federal Government's National Academy of Sciences gave Caltech's great aerodynamicist, Theodore von Karman, $10,000 and told him to turn that amateur effort into a serious jet propulsion laboratory. Thus, almost casually, JPL was born, with Von Karman as director. Without it, U.S. standing in the space race would still be a national embarrassment. In recognition of Von Karman's contribution to space science, President Kennedy last month awarded the 81-year-old scientist-educator the first National Medal of Science.

Today, JPL's lab sprawls across the slopes of the Arroyo Seco. It has grown into a great jumble of miscellaneous structures--from dilapidated trailers to massive, steel-framed buildings and the tidy dome of an astronomical observatory. JPL's duties are a jumble too; it may be asked to tackle any problem connected with space. But everything is dominated by its primary mission: the unmanned exploration of the moon and deeper space.

Still run by Caltech, but directly responsible to the National Aeronautics and Space Administration, JPL has developed into an outstanding example of a peculiarly American administrative invention: a nonprofit scientific laboratory working for the Government but operated by a first-class academic institution. The combination neatly avoids much of the bureaucracy of government and the commercialism of private industry.

Dark Days. Successful as it has been, JPL spent much of its early space career apparently mired in failure. The five Ranger spacecraft it built and launched to explore the surface of the moon in advance of the human astronauts were all spectacular flops. The first two Rangers failed because of bad launchings. Ranger III got launched so vigorously that it reached its rendezvous with the moon before the moon arrived. Ranger IV hit the moon squarely, but its computer brain went dead and it took no pictures. Ranger V lost its solar power supply, and its batteries failed.

Those were dark days. But every Ranger carried telltale instruments to report by radio on the performance of its myriad parts. Each failure became a lecture from space on what to do or not to do the next time. Dozens of hints were disentangled from the messages: how to rewire a circuit, how to avoid trouble by adding or subtracting some small part, how to gain redundancy--the ability to provide duplication for a function that might fail.

JPL's need for more and more information was insatiable. While the Rangers were failing, and teaching by their failures, it was already working on the more ambitious Mariner project for the exploration of Venus. And long before the first Mariner was launched, the new project was in desperate trouble. Centaur, the liquid-hydrogen second-stage rocket that was supposed to be ready to launch a hefty, 1,050-Ib. spacecraft by the summer of 1962, fell far behind schedule. The delay demanded a difficult decision: Should the Venus project be postponed indefinitely or should the Mariners be redesigned in a version light enough to be launched by the Atlas-Agena rocket combination that boosted the Rangers? The new Mariner would weigh in at a meager 447 Ibs., which would mean abandoning many of the important Venus-observing instruments.

Demanding Atmosphere. The decision itself was NASA's problem. But JPL's share of the calculations was the responsibility of Director Bill Pickering. The Caltech physicist had been training for the task almost all his life.

Bill Pickering was born in Wellington, New Zealand, on Christmas Eve 1910. As a youngster, he spent his spare time tinkering with radios and organizing a club of fellow radio amateurs. At the University of New Zealand, he studied electrical engineering, and when an uncle offered to stake him to further education he wasted no time moving to Caltech in Pasadena.

Pickering got to Caltech at a time when the campus was alive with such great teachers as Dr. Robert Millikan, and the demanding academic atmosphere they developed was just what the young scientist needed to egg him on. "He spoke in a thick cockney accent," remembers one of Pickering's early instructors. "I had trouble understanding what he was saying, but I soon found out that my trouble was often caused by my own vagueness about the answers to the questions he raised. There wasn't any doubt about his competence. He was the best in the class."

Pickering's progress was smooth and steady. B.S., M.S., Ph.D.--he got all the requisite degrees. He stayed on in Pasadena to join the Caltech faculty, get married to a pretty Pomona girl named Muriel Bowler and conduct cosmic ray studies under Millikan. In 1944, when JPL missiles and rockets had become sophisticated enough to require a cargo of accurate telemetering equipment, Pickering was the inevitable choice to supervise the work; he was an acknowledged expert in the electronics art of long-distance measurement and control.

After putting grasshopper-light radio equipment on high-flying cosmic-ray sounding balloons, making rockets tell about their troubles was simple. Says Caltech Aerodynamics Professor Homer Joe Stuart, a JPL pioneer: "It is interesting to think what the Germans could have done with a Pickering. We learned after the war that they conducted 1,700 test flights with V-2 rockets. That number is unbelievable until you remember that they had no telemetry worth the name. Their severe security kept their best electronics people from coordinating with their rocket program."

By 1957, when Sputnik I beeped around the earth, jolting the U.S. out of its scientific complacency, Pickering was already in command at JPL. The lab wasted no time in mourning the national setback, for the crisis brought a happy change in its mission. Before Sputnik, it had largely been concerned with military missiles, now it became the scientific center of an invigorated U.S. space campaign. In only 83 days, JPL quickly modified a test rocket, the Jupiter C, and tossed Explorer I, the first U.S. satellite, into Earth orbit.

Getting Explorer aloft was largely a Pickering triumph. He hurried to Washington and hollered at Army generals, urging them to demand permission to launch the satellite. He waved his finger and banged on desks, and the generals gained courage from his indignant earnestness.

Five years later, Explorer is still orbiting,* still testifying to Pickering's administrative and engineering skill. To some of the men who worked on that dramatic crash program, no other space vehicle will ever hold quite the same allure. At an Explorer anniversary party recently, one of its builders commemorated the occasion with a limerick:

Each, in his separate way,

Drinks to a bygone day.

The Explorer, in truth,

Was part of our youth,

And not only orbits decay.

Gung-Ho. Pickering nourishes no such sentimental attachment to the past. Faced with the touchy problem of whether JPL could build a 447-lb. Mariner, he dug into his work with the quiet devotion that is much more characteristic of him than his loud Explorer forays into Washington officialdom. He held endless meetings, consulted everybody worth a hearing. One scientist who heard that a pet instrument would have to be abandoned on the newer, smaller satellite got so emotional that he was almost fired to keep the peace. Pickering never lost his composure. "I had to establish," he says in measured tones, "that the project could get the necessary support from the laboratory, and that we could redesign the spacecraft down to what Atlas-Agena could carry. We finally decided that we could go gung-ho for Venus. When all this looked as if it were making sense, NASA said. 'Charge.' "

The decision sent JPL into a paroxysm of technical creativeness; Mariner would have to leave the earth when Venus was in a favorable position--something that happens in 19-month cycles. Next chance was the summer of 1962, about nine months from the time the big decision was made. "There's an old saying," says Pickering dryly, "that any worthwhile project takes nine months."

To meet the June deadline, when the first Mariner of a series of three would have to be ready at Caoe Canaveral, the lab worked furiously. The designers used the basic frame of the ill-starred Ranger, added equipment needed for the longer voyage to Venus, and used the remaining weight allowance for as many observing instruments as could be squeezed in. Tests were run on every part, arguments raged. Pickering presided calmly and quietly over the melee. He commuted back and forth to NASA's Washington headquarters on the night plane, the "Red Eye," carrying reassurance in both directions. Says Dr. Wernher von Braun of Pickering's administrative style: "His most outstanding characteristic is his ability to lead that most difficult breed of men. the scientists. They can be exceptionally pigheaded. You have to give them enough rope to argue their views. If Bill tried to run a very tight show at JPL. he would risk losing some of his best people."

Sparkling Jewel. Pickering gave lots of rope, but no one got entangled in it, and the first Mariner was produced on schedule. It was a strange and beautiful object, worthy to be displayed like expensive jewelry against a black velvet background. Its feather-light tubular framework was brightly polished aluminum; parts made of magnesium were plated with yellow gold. Its solar panels were reddish purple, like wings of a giant butterfly, and gay little highlights sparkled all over its structure. Unseen in its golden hexagonal abdomen were electronic muscles, organs, brains and ganglia, woven together with hair-thin wire. Mariner I, designed for windless and weightless space, looked delicate, but when folded in the chrysalis position, it could take G forces that would crush that juicy colloid, the human body.

On July 22, with Venus in perfect position for an easy encounter, Mariner I took off from Canaveral. For a while its Atlas climbed properly; then it began to yaw like a monstrous fish trying to shake a hook. All Canaveral watched in dismay as the great rocket snaked across the sky. The safety officer touched his destruct button, and the whole vehicle dissolved into a burst of orange flame and a shower of smoking shards.

Parked in Space. The disaster nearly destroyed us, says Project Manager Jack James. "We were really low. There was a what's-the-use attitude that lasted about five days. But then we began to think about Mariner II. Everything was riding on the next one." The lab's morale came surging back. "They have tremendous esprit at JPL," says Dr. James Van Allen, discoverer of the Van Allen radiation belt and a longtime Pickering admirer. "It's almost offensive. It's like the Marines."

Mariner II, golden and gleaming, was ready on the pad by Aug. 27, when Venus was still in friendly position. This time the launch went perfectly. The Agena second stage, with Mariner II in its nose, went smoothly into parking orbit. After 16 minutes, its engine fired again, soaring out on a curving course that would lead to Venus. A few minutes later, a cluster of exploding pins popped and the spacecraft spread its, wings into the hard sunlight. All this was reported by telemetry to JPL's 85-ft. dish antenna in South Africa and relayed to the control center at the lab. "We were flying blind during lift-off and injection," says Bill Collier, Assistant Project Manager. "But about the time the panels came open, there was a shift of facial styles from worried scowls to big fat grins." Mariner II was safely delivered, apparently thriving in its adult environment, and on its way to Venus.

To scrutinize its target at the end of its long voyage, the spacecraft carried two radiometers, one of them sensitive to radio microwaves, the other to infra-red rays. Each type of radiation behaves differently when passing through clouds or gases; the frequencies were selected to tell as much as possible about the temperature of Venus and the nature of its atmosphere.

13,000 Moons. Although at its closest Mariner was still 21,000 miles away from Venus, a human observer riding the spacecraft would have seen a spectacular sight. Even from 500,000 miles, Venus would be a crescent twice as high as the crescent moon. Because of its high reflectivity and nearness to the sun, it would be much brighter than any moon. As Mariner II swept nearer, its rider would have seen the crescent, growing and thickening, its glare waxing blindingly bright, until it was 35 times the diameter of the full moon as seen from the earth and more than 13,000 times as brilliant.

While the earth turned on its daily round and Mariner II cruised toward Venus, JPL's three great radio dishes, at Johannesburg, South Africa, Woomera, Australia, and Goldstone, Calif., picked up Mariner's reports. They were received as a quavering, singsong radio signal, then translated by a computer into an endless series of letters printed on a broad band of paper. Out of the apparently meaningless melange of characters, Mariner men in JPL's control room deciphered their spacecraft's chatter.

During the triumphant flyby, some of the messages read clearly, telling that the instruments were working well and observing Venus properly. But at other times, the code was jumbled. Apparently two faraway instruments were trying to talk at once. So the necessary parts of a duplicate Mariner were set up in a laboratory and made to observe, in effect, a simulated Venus. When the lab instruments also talked out of turn, they gave a key for disentangling the mixed-up messages from Mariner 'II. These tediously deciphered reports are what were made public last week.

Hot All Over. Mariner's instruments scanned Venus three times, crossing first the dark side, then the boundary between light and dark, and finally the sunlit side. The microwave radiometer reported a surface temperature of about 800DEG F. (melting point of lead: 621.5DEG F.), which seems to vary hardly at all over the whole planet, dark side as well as light side. It showed no detectable water vapor.

Readings on the two infra-red wave lengths were essentially identical. This could be interpreted to mean that there were no breaks in the Venusian clouds and that the infra-red waves came from a high, opaque cloud deck. The amount of carbon dioxide above this deck was too small to be detected.

Infra-red readings also showed the temperature on top of the cloud deck to be about --30DEG F. It varied little over the planet except in one spot at the southern end of the boundary between light and dark, where it fell to about -50DEG F. No one is sure what this means. Perhaps the clouds are higher or more opaque at this point. Perhaps a surface feature, such as a high mountain, forces them upward.

The instruments made another important observation: the limb (edge) of the Venusian disk appears darker than the center. This "limb darkening" means that microwaves and infra-red radiation really originate at the surface or at some level below the top of the atmosphere. Rays coming from the limb must pass slantwise through a greater thickness of atmosphere, and so appear weaker. This rules out one of the leading theories about the Venusian atmosphere: that it is highly ionized on top and therefore glows, making the planet appear hotter than it really is. Such an atmosphere would be brighter at the edges than in the center, and since the Venusian atmosphere does not show this, Venus can have no shell of ions to hide a temperate surface behind a glowing screen.

Physicist Louis D. Kaplan of the University of Nevada and JPL, who helped design Mariner II's infra-red experiment, thinks that at ground level, Venus' atmospheric pressure may be 10 to 20 times that of Earth. Its dry, unbreathable air contains perhaps 10% carbon dioxide (v. .03% for Earth) and probably a little nitrogen. The clouds are so dense that the surface is probably dark. Radar waves bounced off Venus indicate rather uncertainly that there may be both mountains and smooth places, as on the earth.

Hydrocarbon Clouds. The famous Venusian clouds remain a tantalizing mystery. Some astronomers believe that they are fine dust, kicked up from the surface by tremendous winds in the dense atmosphere, but Professor Kaplan has a more picturesque theory. He thinks they are hydrocarbon droplets similar to the water droplets in earthly clouds. The droplets condense in the cool top of the atmosphere, but stay in vapor form in the lower parts, where the temperature rises above 200DEG F. So the dark Venusian surface has clear, compressed, oily air. Infra-red rays from the sun penetrate both clouds and atmosphere, but are hindered by the CO2 when they try to escape. This trapped energy keeps the surface so hot that no life known on Earth could possibly survive there.

Evidence from radio telescopes shows that Venus rotates very slowly, if at all. It may cruise around the sun without turning, which would make its day equal to its year (225 Earth days). Or it may turn slowly enough to keep the same face toward the sun, as Mercury does. In either case, Mariner II's report that the planet's surface is about the same temperature all over calls for some new thinking. During its long, possibly unending night, the dark side should tend to cool off. Why does it stay hot?

Dr. Kaplan's answer is that moderate winds in the planet's thick, dense atmosphere can carry heat enough to keep the dark side warm. The hydrocarbon clouds, 15 miles thick, help by providing the surface with efficient insulation.

While the scientists are still debating the baffling news brought back from Venus, JPL will be gunning for other information beyond the limits of Earth. "Our experience with Mariner II was a modest little nursery-school exercise," says Space Sciences Chief Robert Meghreblian. "It was nothing to compare with what we will do in the next few years."

The next interplanetary shot will probably be aimed at Mars, whether or not the Russian spacecraft which was tossed toward Mars on Nov. 1, finally arrives. Since Mars has a nicely transparent atmosphere, the U.S. Mars shot, now scheduled for 1964, will try to take 20 fine-detail pictures during its flyby, store them on tape, and send them slowly and accurately back to Earth. An infrared spectrometer will look for organic compounds whose presence would almost prove the existence of life.

Venusian Gales. The recent Mariner shot was so successful that it need not be repeated. The next Venus probe will be much more sophisticated. Dr. Meghreblian thinks that Venus is probably plagued by terrific winds, and he wants the next spacecraft to drop a capsule into the planet's clouds to release tough-skinned balloons that will drift with the Venusian gales. A few such balloons, carrying radios that can be followed by an orbiting spacecraft, should tell a lot about the planet's meteorology and perhaps explain what the mysterious clouds are made of.

The nearby moon, which has high priority because of the project to land live astronauts there, will be examined later this year by improved Rangers, and then by more elaborate craft. They will study the lunar surface so that larger craft, eventually carrying humans, can land there safely. Any astronaut touching down in a spaceship needs to know whether the surface below is hard rock or deep, soft dust, whether it is radioactive or made of wholly unknown moon-stuff that cannot exist on Earth.

Silicon Life. When JPL's space denizens have learned to land softly on the moon, they can do the same on Mars, studying or even fighting off any kind of life that exists there. That life may be based on unfamiliar chemistry, perhaps using silicon in place of carbon and some other solvent in place of water. After Mars, comes Jupiter, the monster planet that seems to be bursting with unexplained commotion.

Ranging far out into the solar system, unmanned spacecraft will feel at home in vacuum, be unbothered by radiation, take advantage of weightlessness, get their energy from sunlight as green plants do on Earth. They will perform elaborate maneuvers in response to orders built into their brains, like the instincts of insects, which lead thoroughly successful lives without a trace of reason. Sometimes they will listen with sensitive radio ears for whispers of command from millions or hundreds of millions of miles away. Some of them will send tough-skinned projectiles down into hostile atmosphere and record what they report; some will land on distant planets and survey the landscape with sharp, electronic eyes. With Mariner's success to prove it can be done, scientists are now sure that wherever human astronauts may venture, unmanned spacecraft, like Kilroy, will have been there before them.

* A record that has been verified by the sky-scanning radars of the North American Air Defense Command. While watching for unfriendly bombers and missiles. NORAD's sharp electronic eyes also spot every other high-flying metallic object that comes into range--including research spacecraft. NORAD has counted 273 man-made objects orbiting earth. Some are satellites, living or dead, but most are "garbage": the burned-out rockets, connecting rings, nose covers, and other bits and pieces that are abandoned after accompanying spacecraft into orbit. The oldest of these far-out travelers is Explorer I, launched Jan. 31, 1958. Its orbit is beginning to decay. But Vanguard I, launched a month and a half later, is in higher orbit, and may stay aloft for another 1,000 years.

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