Apollo 8

• 1. Introduction

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  The night before Apollo 8 launched, Charles Lindbergh and his wife Anne Morrow Lindbergh visited the crew at Kennedy Space Center. Lindbergh described how he had prepared for his 1927 transatlantic crossing. He measured the New York to Paris route using a piece of string on a globe, then calculated his fuel from that. The total fuel he had carried for that journey equaled a tenth of what the Saturn V would burn every second of its flight. The next morning, the Lindberghs watched the launch from a nearby dune.

  On the 21st of December, 1968, Frank Borman, Jim Lovell, and William Anders became the first humans to leave Earth's gravitational sphere of influence. They were headed to the Moon on a mission that had been entirely reconceived just four months earlier. The year had brought political assassinations, unrest in the streets of Europe and America, and the crushing of the Prague Spring. What drove three men, and an entire space agency, to attempt something no human had ever done, in the most turbulent year many people alive could remember?

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• 2. The Cold War's Wager

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  On the 4th of October, 1957, the Soviet Union launched Sputnik 1, the first artificial satellite. The launch set off a crisis that went beyond technology. It demonstrated that the Soviet Union could deliver nuclear weapons across intercontinental distances. It also challenged American claims of military, economic, and technological superiority.

  President John F. Kennedy concluded that the perception of American power mattered at least as much as its reality. He needed a challenge that could be won. The Soviet Union's heavier rockets meant he had to choose a goal that neither side could achieve with the technology then available. Something spectacular was required, even if it could not be justified on purely military, economic, or scientific grounds.

  Kennedy chose the Moon. After consulting his advisors, he committed the United States to landing a man on the Moon and returning him safely to Earth before the decade ended. The project already had a name: Project Apollo. A key engineering decision followed: lunar orbit rendezvous. Under this approach, a specialized craft would descend to the lunar surface while the rest of the spacecraft waited above in orbit.

  A command module, service module, and lunar module made up the Apollo spacecraft. The command module housed the three-person crew and was the only part that would return to Earth. The service module provided propulsion, power, oxygen, and water. The lunar module carried the crew to the surface and back up to orbit. All three could be launched by a rocket then under development: the Saturn V. NASA adopted a seven-step plan for Apollo missions in September 1967, with the final step being the Moon landing itself. Within a year, a manufacturing problem would force that plan to be rethought entirely.

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• 3. A Mission Reinvented

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  In June 1968, the lunar module designated LM-3 arrived at the Kennedy Space Center, and engineers uncovered more than a hundred significant defects. Bob Gilruth, director of the Manned Spacecraft Center, concluded that LM-3 had no realistic prospect of flying in 1968. Delivery might slip as late as February or March 1969. Following the original schedule would have delayed Apollo 8 and every subsequent mission, threatening the 1969 Moon landing goal.

  George Low, the Manager of the Apollo Spacecraft Program Office, proposed a solution in August 1968. The next command and service module, designated CSM-103, would be ready three months before LM-3. Rather than repeating the previous Earth-orbit test, that module could be sent all the way to the Moon.

  On the 9th of August, Low presented the idea to a group that included Kurt Debus, Rocco Petrone, Wernher von Braun, and flight director Chris Kraft. Kraft judged the proposal feasible from a flight control standpoint. Debus and Petrone confirmed the Saturn V designated AS-503 could be ready by the 1st of December. Von Braun was confident the pogo oscillation problems from Apollo 6 had been fixed. Only NASA administrator James E. Webb needed persuading before he authorized the mission. Apollo 8 was officially redesignated as a lunar-orbit flight.

  The redesignation came with real costs. Borman's crew had two to three months less preparation time than originally planned. Their lunar module training was replaced entirely by translunar navigation training. James McDivitt, whose crew had trained for the LM test, was offered the redesigned mission and turned it down. He still wanted to fly the flight he had prepared for.

  The Soviet Union added urgency. The Zond 5 spacecraft flew a loop around the Moon in September 1968, carrying Russian tortoises and other living creatures. It returned them to Earth on the 21st of September. American reconnaissance satellites had observed a Soviet N1 rocket mockup being rolled to the launch pad at Baikonur on the 25th of November, 1967. Speculation inside NASA and in the press grew that a crewed Soviet circumlunar flight might come before the year was out.

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• 4. Building a Safe Rocket

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  Apollo 6, which flew in April 1968, had suffered three serious failures. Severe pogo oscillation shook the first stage during ascent. Two second-stage engines quit in flight. And the third stage failed to reignite in orbit. Without assurance that each of these problems was solved, no NASA administrator could justify placing a crew on the Saturn V.

  Engineers at the Marshall Space Flight Center traced the pogo oscillation to a resonance effect. The engines vibrated at a frequency that matched the natural frequency of the rocket structure itself. That alignment amplified the shaking into dangerous feedback. A helium-gas absorption system was designed to dampen the vibrations at the source.

  The engine failures had a chain-reaction cause. A hydrogen fuel line that leaked when exposed to vacuum caused a loss of pressure in engine two. An automatic shutoff intended to close engine two's liquid hydrogen valve instead cut engine three's liquid oxygen supply through a miswired connection. Engine three failed within one second of engine two. A separate investigation found that the third-stage failure had a different cause: a faulty igniter line.

  Teams from the Marshall Space Flight Center tested their solutions in August 1968. One Saturn stage, fitted with shock-absorbing devices, demonstrated the pogo fix. A second stage equipped with modified fuel lines showed they would not rupture under vacuum. Once NASA administrators accepted the results, they approved the Saturn V designated AS-503 for a crewed mission.

  The spacecraft was mated to the rocket on the 21st of September. On the 9th of October, the full assembly rode one of NASA's crawler-transporters on the three-mile journey to the launch pad. Testing continued through December. Final verification of the pogo, fuel line, and igniter modifications was completed on the 18th of December, three days before the scheduled launch.

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• 5. Three Days to the Moon

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  At 12:51:00 UTC on the 21st of December, 1968, Apollo 8 lifted off from the Kennedy Space Center. At 2 hours, 27 minutes, and 22 seconds after launch, CAPCOM Michael Collins radioed: "Apollo 8, you are Go for TLI." The third stage ignited and burned for 318 seconds. It boosted the spacecraft from 25,567 to 35,505 feet per second, setting a record for the fastest any human had traveled relative to Earth.

  While rotating the spacecraft to photograph the spent third stage, the crew glimpsed the whole Earth at once. No human had ever seen it that way before. Borman grew worried the stage was staying too close and arranged a separation burn. Five hours after launch, Mission Control vented the stage's remaining fuel. It drifted into a solar orbit with a period of 340.80 days, a derelict object still circling the Sun.

  Apollo 8 became the first crewed spacecraft to cross the Van Allen radiation belts, which extend up to 15,000 miles from Earth. Scientists predicted the exposure would be no worse than a chest X-ray, around 1 milligray. Each crew member wore a Personal Radiation Dosimeter that transmitted readings to Earth, plus three passive film dosimeters for cumulative measurement. By the end of the mission, the average dose was 1.6 mGy per crew member.

  Frank Borman fell ill during the outward cruise, vomiting twice and suffering a bout of diarrhea. The spacecraft briefly filled with floating globules that the crew cleaned up as best they could. Borman wanted to keep it private. Lovell and Anders persuaded him to record a description on the Data Storage Equipment for Mission Control to review. Doctors concluded it was either a 24-hour flu or a reaction to a Seconal sleeping pill. Researchers now believe it was space adaptation syndrome, which affects about a third of astronauts during their first day in weightlessness.

  The spacecraft rotated slowly around its long axis throughout the cruise in a thermal management technique engineers called the "barbecue roll." Without it, parts in direct sunlight could reach over 200 degrees Celsius while shadowed parts dropped to minus 100 degrees. The crew made small attitude corrections every half hour to keep the rotation cone from drifting.

  At 55 hours and 40 minutes into the flight, Apollo 8 crossed into the Moon's gravitational sphere of influence. The crew were then 38,759 miles from the Moon and moving at 3,990 feet per second relative to it. They continued calculating their trajectory against the Kennedy Space Center launch pad until the final course correction. At 68 hours, Mission Control confirmed they were Go. Lovell replied, "We'll see you on the other side." Apollo 8 slipped behind the Moon and out of contact with Earth, the first time in human history that had happened.

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• 6. Orbiting the Moon

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  The service propulsion engine ignited at 69 hours, 8 minutes, and 16 seconds after launch and burned for 4 minutes and 7 seconds. The crew described those four minutes as the longest of their lives. The burn placed Apollo 8 into an initial elliptical orbit: 193.3 miles at its highest, 69.5 miles at its lowest. A second burn circularized the orbit to roughly 60 nautical miles above the surface. The spacecraft would spend the next 20 hours completing ten circuits of the Moon.

  Jim Lovell gave the first human description of the lunar surface. The Moon, he said, looked "essentially grey, no color; looks like plaster of Paris or sort of a grayish beach sand." He called Langrenus "quite a huge crater," with a central cone and walls terraced in six or seven levels. One of the crew's primary tasks was reconnaissance of future landing sites. They gave particular attention to a location in Mare Tranquillitatis already selected as the Apollo 11 landing site. The launch time of Apollo 8 had been chosen partly to give the best lighting for that survey.

  Bill Anders spent much of the 20 hours taking photographs. By the mission's end, the crew had taken over 800 photographs on 70 mm film and 700 feet of 16 mm movie footage. During the third orbit, Borman read a prayer for his church. He had been scheduled to attend a service at St. Christopher's Episcopal Church near Seabrook, Texas, that same day. A fellow parishioner and Mission Control engineer named Rod Rose had suggested he record the prayer for playback during the service.

  On the fourth pass around the Moon, Anders saw the Earth emerging above the lunar horizon. NASA's Lunar Orbiter 1 had taken the first Earthrise photograph on the 23rd of August, 1966. No human had ever witnessed the event in person. Anders grabbed a black-and-white camera at once, then asked for color film and took the color photograph. Life magazine later named that image first among its 100 Photographs That Changed the World. Because the Moon's rotation is synchronized with its orbit, Earth stays nearly fixed in the lunar sky as seen from the surface. Earthrise is visible only from orbit, or from select spots near the lunar limb where libration briefly lifts Earth above the horizon.

  As the crew rounded the Moon for the ninth time, Borman introduced the second television broadcast. He described the view as "a vast, lonely, forbidding expanse of nothing." Anders then announced that the crew had a message for all those on Earth. Each man read a section of the first ten verses from the Book of Genesis. Borman's closing words: "And from the crew of Apollo 8, we close with good night, good luck, a Merry Christmas and God bless all of you, all of you on the good Earth." At the time, the broadcast was the most watched television program ever made. An estimated quarter of all people alive at the time saw it, either live or on a delay.

  The most critical burn of the mission came next: the trans-Earth injection. It had to be performed on the far side of the Moon, out of all contact with Earth. Any failure to ignite would have left the crew stranded with no means of rescue. The engine fired exactly on schedule. The spacecraft reappeared at precisely 89 hours, 28 minutes, and 39 seconds. Lovell announced: "Please be informed, there is a Santa Claus." Apollo 8 turned for home on Christmas Day.

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• 7. Coming Home

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  During the return cruise, Lovell used idle time to practice navigational star sightings on the Apollo Guidance Computer. While maneuvering the module to align on stars using the keyboard, he accidentally erased a portion of the computer's memory. The inertial measurement unit then concluded the module was in its pre-launch orientation and fired the thrusters to match it. Lovell spent ten minutes working out the correct realignment. He used the thrusters to align on Rigel and Sirius, then took another 15 minutes to enter the corrected data. Sixteen months later, during Apollo 13, he would face a similar problem under far more critical conditions. On that mission, the module's inertial platform had to be shut down to conserve power.

  On Christmas afternoon, Deke Slayton had left a surprise in the food locker. It was a real turkey dinner with stuffing, in the same type of food pack given to troops in Vietnam. He had also stowed three miniature bottles of brandy. Borman ordered the crew to leave them unopened until after landing. They remained unopened for years after the flight. The crew's wives had added small personal gifts of their own.

  As the command module hit the upper atmosphere, plasma formed around the exterior and the spacecraft began to slow. Deceleration peaked at 6g. The computer guided the spacecraft in a brief skip off the upper atmosphere before the final descent. At 30,000 feet the drogue parachute deployed, followed at 10,000 feet by the three main parachutes. The spacecraft splashed down in the North Pacific Ocean, southwest of Hawaii, at 15:51:42 UTC on the 27th of December, 1968. The parachutes dragged the module upside-down into the 10-foot swell, a condition called Stable 2. Flotation balloons righted it about six minutes after splashdown. The first US Navy frogman reached the capsule 43 minutes after impact. Forty-five minutes later, the crew stepped onto the flight deck of their recovery aircraft carrier, having traveled a maximum distance of 203,752 nautical miles from Earth.

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• 8. What It Meant

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  Time magazine named the Apollo 8 crew its Men of the Year for 1968. The crew themselves had rated the mission's chances of full success at no better than fifty-fifty. Apollo 11 astronaut Michael Collins said: "Eight's momentous historic significance was foremost." Space historian Robert K. Poole called Apollo 8 the most historically significant of all the Apollo missions.

  Twelve hundred journalists covered the mission, more than for any American spaceflight since John Glenn's Mercury-Atlas 6 orbital flight in 1962. The BBC broadcast coverage across 54 countries in 15 languages. Even the Soviet newspaper Pravda ran a quote from the chairman of the Soviet Interkosmos program. He described the flight as "an outstanding achievement of American space sciences and technology." The broadcasts from space won an Emmy Award, the highest honor given by the Academy of Television Arts and Sciences.

  The Earthrise photograph has been cited as an inspiration behind the first Earth Day, held in 1970. Eighteen days after returning to Earth, the crew appeared in the Super Bowl III pre-game show, in January 1969, to recite the Pledge of Allegiance. The national anthem that followed was performed by trumpeter Lloyd Geisler of the Washington National Symphony Orchestra.

  Madalyn Murray O'Hair, an atheist, filed a lawsuit against NASA over the Genesis reading. She argued that government employees should not pray publicly while in space. The Supreme Court dismissed the case, apparently for lack of jurisdiction in outer space. The controversy left NASA cautious about religion throughout the rest of the Apollo program. On Apollo 11, Buzz Aldrin self-communicated Presbyterian Communion on the lunar surface. He declined to mention it publicly for several years, referring to it only obliquely at the time.

  In January 1970, the Apollo 8 command module was shipped to Osaka, Japan, for display in the American pavilion at Expo '70. It is now on permanent display at the Chicago Museum of Science and Industry. Alongside it are personal items donated by Jim Lovell and the space suit Frank Borman wore on the mission. Jim Lovell's space suit is on display at the Visitor Center at NASA's Glenn Research Center. Bill Anders's suit is at the Science Museum in London.

  In 1969, the United States Post Office Department issued a commemorative stamp, Scott catalogue number 1371. It featured a detail from the Earthrise photograph and the words "In the beginning God...", the opening line of Genesis. The band Public Service Broadcasting built their 2015 track "The Other Side" around actual Apollo 8 recordings. The song appears on the album The Race for Space. Nearly six decades on, the recordings of what Borman, Lovell, and Anders said from behind the Moon continue to reach new listeners.

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