Once Upon A Time, Bombing The Moon Was A Great Idea

Withal, the “live” television coverage of Alphonsus was popularly judged Ranger 9’s most impressive accomplishment. Everyone in North America with access to a television set had been able to watch the event and, as if holding a visual subscription to the National Geographic, experience firsthand the thrill of exploring the unknown. Relenting somewhat of its earlier opinion, The Christian Science Monitor offered “awed congratulations to all those involved in giving the public – ‘live,’ in ‘real time’ – the sequence of pictures sent back by Ranger.” “High and historic drama,” The New York Times added, terming the mission “astronomy for the masses,” and “the finest type of space research at this stage of history.” The people had participated, though the meaning and the medium of the experience remained scrambled. One local correspondent said it succinctly: “For most of us the pictures didn’t look like much, but the mere fact of seeing them gave us a front row seat on science.”

President Johnson watched on a television set at the White House. Ranger 9, and the manned Gemini spacecraft launched successfully for a three-orbit mission around the world during Ranger’s flight to the moon, assuaged much of the concern generated by the “spacewalking” Russian a week before. After the impact inside Alphonsus, the President issued a public statement exuding fresh confidence: “Ranger 9 showed the world further evidence of the dramatic accomplishments of the United States space team … Steps toward manned flight to the moon have become rapid and coordinated strides, as manned space maneuvers of one day are followed by detailed pictures of the moon on the next.”

Called to the White House forthwith, James Webb briefed President Johnson and the members of his Cabinet on Ranger’s photographs and their implications for Project Apollo.

THE RANGER LEGACY

Ranger was accounted to have cost $267 million, and observers wonder whether the project was worth the time, the money, and the careers it claimed. Perhaps not for sky scientists, whose experiments were left out of all but the ill-fated Block I flights. Perhaps not, it seemed at the time, even for planetary scientists. The lunar photographs supplied no decisive evidence about the formation, structure, or strength of the lunar surface. “Ranger’s pictures are like mirrors,” the planetary scientist Thomas Gold mused after the flight of Ranger 9, “and everyone sees his own theories reflected in them.” So indecisive a scientific outcome had virtually been ensured by the redirection of Project Ranger to serve Apollo, the eventual elimination of all experiments save the television cameras and, with the cancellation of Ranger Block V, of any nonvisual experiments to probe the moon’s surface composition and structure.

But, along with besting the Soviet Union in sending back to earth the first television pictures of the lunar surface, Ranger had eliminated any doubts about the adequacy of the design for the Apollo lander. It had also taught many space scientists that in space exploration, engineering would often have to come first. Homer Newell, Mr. Science at NASA, had learned that lesson and now patiently explained to scientists and Congressmen alike the knowledge to be won from the spectacular engineering task of Apollo. Who first stepped on the moon, he insisted, was not the issue; the individuals could stay but a short time. The scientific instruments they would use, those they would leave behind on the surface, and the soil samples they would retrieve would all yield rich scientific dividends. He was, as events were to prove, absolutely right.

No less important, the Ranger project itself had already quickened the pace of planetary science. It had helped the research preferences of planetary scientists assume a preeminent place in the councils of space science. It had made visual imaging a basic exploratory tool of planetary science, an accepted antecedent to the planning of further experiments. Ranger’s pictures themselves provided detailed lunar maps and the means to construct three-dimensional lunar surface models.

Scientists observed for the first time craters from one meter to a few hundred meters in diameter, and, from the makeup of the moonscape, deduced evidence of vulcanism. The steady-state distribution of small craters was also discovered, and detailed evidence was first observed for the aging and evolution of individual craters and other surface features as a result of repetitive bombardment of the lunar surface by solid particles. In all, the television pictures acquired by Rangers 7, 8, and 9 created the foundation of a provocative new discipline – the science of the lunar regolith – the study of the fragmented debris that makes up the moon’s surface.

In Project Ranger, the Deep Space Network generated tracking data that improved knowledge of the mass of the moon by an order of magnitude. From these same data scientists found the radius of the moon to be 3 kilometers less than the previously accepted value, and they discovered an offset between the geometrical center of the moon and its center of mass – a discovery with profound implications for understanding the lunar interior. Kuiper correctly remarked after the flight of Ranger 7 that lunar exploration had entered a new era; the project had transformed the centuries-old study of the moon from subtle conjecture to an experimental science.

Perhaps more than any other flight project, Ranger proved the technologies and the designs for the automatic machines NASA would use for deep space exploration: attitude stabilization on three axes, onboard computer and sequencer, directional scientific observations, midcourse trajectory and terminal maneuver capability, and steerable high-gain antenna. With Ranger, NASA’s Deep Space Network perfected the two-way doppler tracking and communications system, including the means to measure the velocity between the spacecraft and tracking stations – the key to accurate trajectory computation. Television camera improvements, such as fast erasing and shuttering technology, became available to other projects. Ranger also broke new technical ground for NASA by using the Atlas-Agena B launch vehicle, by the parking orbit technique, and, less happily perhaps, by heat sterilizing spacecraft components.

In 1965 NASA officials also liked to claim that Ranger might possibly benefit the commercial and scientific market places. Knowledge gained in building the impact-limiter capsule, they suggested, could be transferred and adapted to deliver sensitive instruments for earth exploration, airdrop supplies to disaster victims, and improve collision-proofing of vehicles and the packaging of parcels. By 1976, only one case of such uses was known – the modification of Ranger’s single-axis seismometer and its capsule to function in earth gravity and at various pressures, which has served the University of California’s Institute of Geophysics and Planetary Physics at La Jolla well for 13 years of seismological observations on the ocean bottom, in midwater, and on land.