27 December 1968 15:51:42 UTC, T plus 147:00:42.0: Apollo 8 splashes down in the Pacific Ocean south of the Hawaiian Islands, within 5,000 yards (4,572 meters) of the recovery ship USS Yorktown (CVS-10). The spacecraft arrived before sunrise, landing in 10-foot (3-meter) swells. The parachutes dragged the capsule and left it floating upside down. The inflatable pontoons righted it after about six minutes.
The three astronauts, Frank F. Borman II, James A. Lovell, Jr., and William A. Anders, were hoisted aboard a Sikorsky SH-3D Sea King helicopter, Bu. No. 152711, and flown to the aircraft carrier.
Apollo 8 was the first manned space mission to leave Earth orbit and to travel to another planetary body. It proved all of the space flight techniques that would be required for the upcoming Apollo 11 landing on the Moon.
Sikorsky SH-3D Sea King 66, Bureau of Aeronautics serial number 152711, assigned to HS-4 (“Black Knights”) was the primary recovery helicopter for Apollo 8, Apollo 10, Apollo 11, Apollo 12 and Apollo 13. It was lost at sea off NALF Imperial Beach, California, 4 June 1975. One crewman was killed.
25 December 1968: During the 10th orbit of the Moon, the crew of Apollo 8 fired the Service Propulsion System (SPS) of the Command Service Module for the Trans Earth Injection (TEI) maneuver that would send them home.
TEI was a critical maneuver which had to be timed perfectly. It occurred while the spacecraft was on the side of the Moon away from Earth, and so the crew was out of radio communication with Mission Control in Houston, Texas. If initiated too soon, the Apollo capsule would miss Earth, or ricochet off the atmosphere. Too late and the capsule would re-enter too steeply and burn up.
The engine had to burn for precisely the correct amount of time to accelerate the space craft out of lunar orbit and to arrive at Earth at exactly the correct point in space where where our home planet would be 57 hours, 26 minutes, 56.2 seconds later, as it traveled in its orbit around the Sun.
The SPS engine was an AJ10-137, built by Aerojet General Corporation of Azusa, California. It burned a hypergolic fuel combination of Aerozine 50 and nitrogen tetraoxide, producing 20,500 pounds of thrust (91.19 kilonewtons). It was designed for a 750 second burn, or 50 restarts during a flight. The SPS engine had already been used for the Trans Lunar Injection maneuver, sending Apollo 8 from Earth orbit to the moon, and now served the same function in reverse.
The SPS started at mission time T+089:19:16.6 and cut off at T+089:22:40.3, a burn duration of 3 minutes, 23.97 seconds, increasing the velocity (Δv, or “delta–v”) 3,531 feet per second (1,076 meters per second).
“For all the people on Earth the crew of Apollo 8 has a message we would like to send you.”
In the beginning God created the heaven and the earth. And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters. And God said, Let there be light: and there was light. And God saw the light, that it was good: and God divided the light from the darkness.
And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day. And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters. And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so. And God called the firmament Heaven. And the evening and the morning were the second day.
And God said, Let the waters under the heavens be gathered together unto one place, and let the dry land appear: and it was so. And God called the dry land Earth; and the gathering together of the waters called the Seas: and God saw that it was good.
“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.”
This video from the NASA Goddard Space Flight Center describes the taking of this iconic photograph:
21 December 1968: At 12:51:00.7 UTC, Apollo 8 lifted off from Launch Complex 39A at the Kennedy Space Center, Cape Canaveral, Florida. Aboard were Mission Commander, Colonel Frank Frederick Borman II, United States Air Force; Command Module Pilot, Captain James Arthur Lovell, Jr., United States Navy; and Lunar Module Pilot, Major William A. Anders, U.S. Air Force.
The center engine of the S-IC first stage shut down at 00:02.05.9, and the remaining four F-1 engines shut down at 00:02:33.8. First stage separation took place at 00:02:34.5.
The five Rocketdyne J-2 engines of the S-II second stage fired at 00:02.35.2. The launch escape tower was jettisoned at 00:03:08.6. The engine shut down at 00:08:44.0.and the second stage was jettisoned at 00:08:44.9.
The single J-2 of the S-IVB third stage ignited at 00:08:45.0, and cut off at 11:25.0. At 00:11:35.0, the Apollo 8 Command and Service Module, the Lunar Module test article, and the S-IVB third stage was injected into a nearly-circular 98 nautical miles × 103 nautical miles (113 statute miles × 119 statute miles/181 × 191 kilometers) Earth orbit.
The S-IVB’s J-2 engine was restarted for Trans Lunar Injection (TLI) at 02:50:37.1, and cut off at 02:55:55.5. Apollo 8 was on its way to The Moon.
Apollo 8 was the second manned mission of the Apollo program. It was the first manned spacecraft to leave Earth orbit, travel to and orbit the Moon, then return to Earth.
The Saturn V rocket was a three-stage, liquid-fueled heavy launch vehicle. Fully assembled with the Apollo Command and Service Module, it stood 363 feet, 0.15 inches (110.64621 meters) tall, from the tip of the escape tower to the bottom of the F-1 engines. The first and second stages were 33 feet, 0.2 inches (10.089 meters) in diameter. Fully loaded and fueled the rocket weighed approximately 6,200,000 pounds (2,948,350 kilograms).¹ It could lift a payload of 260,000 pounds (117,934 kilograms) to Low Earth Orbit.
The first stage was designated S-IC. It was designed to lift the entire rocket to an altitude of 220,000 feet (67,056 meters) and accelerate to a speed of more than 5,100 miles per hour (8,280 kilometers per hour). The S-IC stage was built by Boeing at the Michoud Assembly Facility, New Orleans, Louisiana. It was 138 feet (42.062 meters) tall and had an empty weight of 290,000 pounds (131,542 kilograms). Fully fueled with 203,400 gallons (770,000 liters) of RP-1 and 318,065 gallons (1,204,000 liters) of liquid oxygen, the stage weighed 5,100,000 pounds (2,131,322 kilograms). It was propelled by five Rocketdyne F-1 engines, producing 1,522,000 pounds of thrust (6770.19 kilonewtons), each, for a total of 7,610,000 pounds of thrust at Sea Level (33,851 kilonewtons).² These engines were ignited 6.50 seconds prior to Range Zero and the outer four burned for 161.74 seconds. The center engine was shut down after 135.24 seconds to reduce the rate of acceleration. The F-1 engines were built by the Rocketdyne Division of North American Aviation at Canoga Park, California.
The S-II second stage was built by North American Aviation at Seal Beach, California. It was 81 feet, 7 inches (24.87 meters) tall and had the same diameter as the first stage. The second stage weighed 80,000 pounds (36,000 kilograms) empty and 1,060,000 pounds loaded. The propellant for the S-II was liquid hydrogen and liquid oxygen. The stage was powered by five Rocketdyne J-2 engines, also built at Canoga Park. Each engine produced 232,250 pounds of thrust (1,022.01 kilonewtons), and combined, 1,161,250 pounds of thrust (5,165.5 kilonewtons).³
The Saturn V third stage was designated S-IVB. It was built by Douglas Aircraft Company at Huntington Beach, California. The S-IVB was 58 feet, 7 inches (17.86 meters) tall with a diameter of 21 feet, 8 inches (6.604 meters). It had a dry weight of 23,000 pounds (10,000 kilograms) and fully fueled weighed 262,000 pounds. The third stage had one J-2 engine and also used liquid hydrogen and liquid oxygen for propellant. The S-IVB would place the Command and Service Module into Low Earth Orbit, then, when all was ready, the J-2 would be restarted for the Trans Lunar Injection.
Eighteen Saturn V rockets were built. They were the most powerful machines ever built by man.
¹ The AS-503 total vehicle mass at First Stage Ignition (T –6.585 seconds) was 6,221,823 pounds (2,833,171 kilograms).
² Post-flight analysis gave the total average thrust of AS-503’s S-IC stage as 7,726,936 pounds of thrust (34,371,122 Newtons).
³ Post-flight analysis gave the total average thrust of AS-503’s S-II stage as 1,143,578 pounds of thrust (5,086,888 Newtons).
⁴ Post-flight analysis gave the average total thrust of AS-503’s S-IVB stage as 203,053 pounds of thrust (903,225 Newtons) during the first burn; 201,530 pounds (896,450 Newtons) during the second burn.