Space: The World Is Round

Like all Gemini missions before it, last week’s flight of Gemini 11 was a carefully planned practice session de signed to teach U.S. spacemen as much as possible about the techniques they must master and the troubles they must overcome before landing men on the moon and returning them safely to earth. The practice paid off handsome ly. From its improbably precise launch, made within a tiny, two-second “win dow” of time, to its all-but-perfect splashdown 21 miles from the recovery carrier Guam, Gemini 11 proved to be an able instructor indeed.

Even the flight’s one notable failure —the unexpected early end to Astronaut Richard Gordon’s space walk — provided scientists with valuable data that may help prevent similar problems on future missions. It was also a humbling reminder that for all his powerful rockets, com plex capsules and sophisticated electron ics systems, man’s frail frame itself is the limiting factor in space exploration.

Temporary Blindness. Only minutes after he emerged from Gemini’s open hatch, Astronaut Gordon was in trou ble. Though he had done nothing more than detach a cosmic-ray counter from the spacecraft’s hull and mount a movie camera on a bracket behind the hatch, his heart was beating wildly, he was bathed in perspiration and panting for breath. “I’ve got to rest a minute,” he gasped. “I’m pooped.” After regaining his breath, he inched forward to Gemini’s nose, which was securely locked in the docking collar of the Agena target vehicle. He straddled his ship to steady himself. “Ride’m, cowboy!” called Command Pilot Pete Conrad exuberantly. “How are you doing?” “I’m tired, Pete,” the dejected Gordon admitted.

From a box behind the Agena’s docking collar, Gordon pulled out the looped end of a 2-in.-diameter, 100-ft., Dacron rope, slipped it over the end of Gemini’s l-ft.-long docking bar and clamped it tight. As he crawled back toward his hatch, exhausted by that seemingly simple task, perspiration temporarily blinded his right eye. With that, Conrad ordered him back into Gemini’s cabin, wiping out planned exercises with a hand-held jet maneuvering gun and a power tool for tightening bolts.

Gordon’s troubles, similar to those encountered by Astronaut Eugene Cernan on the flight of Gemini 9, were proof to NASA officials that the mere effort of controlling arm and leg movements during a weightless space walk in a bulky space suit is far more trying than anyone had imagined. As a result, future space flights will probably schedule less ambitious space-walking chores.

Apollo Simulation. Having taught so much with its failure, Gemini was able to demonstrate even more with its many successes. Within 94 minutes after their launch from Cape Kennedy, while they were still on their first orbit, Conrad and Gordon rendezvoused and docked with an Agena target vehicle that had been blasted into orbit only a few hours earlier. It was the first successful space link-up accomplished so soon after launch, and it simulated a vital step in the Apollo moon mission. After exploring the surface of the moon, Apollo astronauts will have to blast off in their little lunar excursion module (LEM); then, after only 11 orbits, they will have to rendezvous and dock with the moon-orbiting Apollo mother ship.

Using the powerful, 16,000-lb.-thrust engine of their captive Agena, the Gemini 11 astronauts also reached the highest altitude ever flown by man. While consuming nearly three-quarters of a ton of fuel in a 25-second burn, the engine increased the Gemini-Agena’s speed by 620 m.p.h. and shoved it into an orbit with an apogee of 850 miles—far exceeding Gemini 10’s record height of 476 miles. As his ship approached maximum altitude, Conrad could not contain his excitement. “It’s fantastic,” he radioed to controllers at Carnarvon, Australia. “You wouldn’t believe it. I’ve got India in the left window, Borneo under our nose, and you’re right at the right window. The world is round!”

Skip Rope Outside. By managing to secure the Dacron tether between the Agena and Gemini 11 before abandoning his space walk, Gordon had set the stage for the most spectacular of Gemini’s maneuvers. On the third day of the flight, Conrad undocked Gemini and used his thrusters to back slowly away from the Agena until the 100-ft. rope was taut between them. As soon as the thrusters were shut off, however, both ships began to gyrate erratically, the rope oscillating between them. “It’s like the Agena and I have got a skip rope between us,” reported Conrad. To stabilize the ships, he again fired Gemini’s thrusters, this time sending the rope-connected ships into a slow, cartwheeling rotation around the system’s center of mass—a point on the rope 35 ft. from the Gemini (see diagram). Gradually, as Gemini and Agena revolved in a giant circle, the rope stretched tight, the oscillations stopped, and the two craft continued in orbit a fixed distance apart.

The experiment clearly proved that tethered spaceships can orbit in formation without wasting fuel. Robert Gilruth, director of NASA’s Manned Spacecraft Center, immediately conjured up “colonies of vehicles fastened together in ways like this.” The slow rotation of the system also provided a bonus: a small centrifugal force that acted like a weak gravitational pull, causing objects to drift toward and finally “fall” on the rear wall of Gemini’s cabin. It was the first artificial gravity created during a manned orbital flight. After three hours of tethered orbiting, Conrad flipped a switch that jettisoned Gemini’s docking bar, freeing the spacecraft from the connecting rope. As Gemini drifted away, the tether—now attached only to the Agena—slowly wrapped itself around the target vehicle like a python around its prey.

“Chimp Mode” Reentry. Earlier, the astronauts had docked a record four times, but they had used their fuel so efficiently that they had enough left to make a final and unscheduled rendezvous with the Agena. At reentry, Conrad and Gordon were relieved of their duties by a new, automatic re-entry system that the astronauts sarcastically call “the chimp mode.” Controlled by Gemini’s onboard computer, it fired the spacecraft’s thrusters at the proper time to correct its attitude and direction. Its value was evident. For it guided the relaxed astronauts to a splashdown closer to the recovery carrier than ever before in the U.S. manned spaceflight program.