Space: Moonward Bound

Startled by the noise, a flock of geese flapped across the cloudy sky, momentarily breaking their V-formation. Below, pulsating pressure waves beat against the faces and chests of reporters sitting in an open grandstand. In the launch-control center, as plaster dust from the ceiling fell around him and technicians wildly cheered, Wernher von Braun breathed, "Go, baby, go. " And in a portable CBS News studio, Commentator Walter Cronkite pressed his hands against a trembling plate-glass window and, in a voice distorted by excitement and vibration, shouted to a nationwide TV audience: "Oh, my God, our building is shaking . . . part of the roof has come in here!"

On Cape Kennedy's launch pad 39A last week, the cause of all the commotion, America's mighty Saturn 5, spewed brilliant flames and rose majestically on a flight that revitalized the lagging Apollo program and raised hopes that the U.S. may yet land men on the moon before 1970. Generating 7,500,000 Ibs. of thrust and one of the loudest sounds ever produced by man,* the first-stage engines lifted the 3,000-ton, 363-foot-high vehicle to an altitude of 38 miles and a speed of 6,100 m.p.h. only 21 minutes after liftoff. During this stage of the flight, the rocket, taller than the Statue of Liberty, could be seen as far away as Jacksonville, 150 miles distant.

Cutting in after the first stage was jettisoned, the liquid-hydrogen-fueled SII second stage fired flawlessly, providing 1,000,000 Ibs. of thrust and boosting the rocket to an altitude of 115 miles before it, too, was jettisoned. Now it was the turn of the third-stage S-IVB. Firing its engine, it inserted itself, the attached Apollo spacecraft, its service module and the lunar module—a total of 140 tons—into orbit, with an apogee of 119 miles, a perigee of 114 miles. It was an impressive demonstration that, after ten years, the U.S. had finally overtaken and surpassed Russia in brute rocket power. The heaviest loads ever orbited by the Soviets were the 13-ton Protons 1 and 2 in 1965.

Interception Path. During its third orbit, the S-IVB refired its engine, increasing its speed to nearly 23,400 m.p.h. and thrusting farther away from the earth. After the S-IVB was separated and the Apollo service-module engine fired briefly, placing Apollo into an orbit with an apogee of 11,200 miles and a perigee of negative 50 miles—meaning that the craft's path would intercept the earth.

As Apollo began to plunge back toward the earth from its peak altitude, its engine again fired, increasing its speed and ensuring that the craft would plunge into the earth's atmosphere at the 25,000-m.p.h. velocity that will be reached by a returning lunar mission. The maneuver was designed to test Apollo's heat shield against temperatures much higher than those encountered by Gemini and Mercury spacecraft, which re-entered the atmosphere from their orbital missions at about 17,000 m.p.h.