21 April 1972, 02:23:35 UTC: Lunar Module Orion (LM-11) touched down on the surface of the Moon at the Descartes Highlands. On board were the Mission Commander, Captain John Watts Young, United States Navy, and Lunar Module Pilot Lieutenant Colonel Charles M. Duke, Jr., United States Air Force. They were the ninth and tenth humans to stand on the Moon.
Technical problems delayed Orion‘s descent for three orbits. Lieutenant Commander Thomas K. (Ken) Mattingly II, U.S.N., the Command Module Pilot, remained in lunar orbit aboard Casper (CSM-113).
As they neared the surface they started to see dust blowing at about 80 feet (24 meters). The lunar module hovered briefly before continued downward.
104:29:22 Duke:Okay, 2 down. Stand by for contact. Come on, let her down. You leveled off.(Pause) Let her on down. Okay, 7. . . 6 percent [fuel remaining]. Plenty fat.
104:29:36 Duke: Contact! Stop. (Pause while they drop to the surface) Boom.
During a debriefing, John Young said, “When we got the Contact light, I counted ‘one-potato’ and shut the engine down. The thing fell out of the sky the last three feet. I know it did. I don’t know how much we were coming down, maybe a foot a second.”
Young and Duke remained on the surface for 2 days, 23 hours, 2 minutes, 12 seconds. During that time, they performed three EVAs totaling 20 hours, 14 minutes, 20 seconds. They drove their Lunar Roving Vehicle 16.6 miles (26.7 kilometers).
A remote television camera was placed on the surface and captured color images of the Lunar Module Ascent Stage departing the Moon for lunar orbit at 01:25:47 UTC, 24 April 1972.
17 April 1970: Apollo 13 splashed down in the Pacific Ocean southwest of American Samoa, landing 4 miles from the recovery ship, USS Iwo Jima (LPH-2).
With their space craft crippled by an internal explosion on 13 April, the planned lunar landing mission had to be aborted. Astronauts James A. Lovell, Jr., John L. Swigert, Fred W. Haise, Jr., worked continuously with engineers at Mission Control, Houston, Texas, to overcome a series of crises that threatened their lives.
17 April 1970: Because of the unusual configuration of the Apollo 13 Command Module, Service Module and Lunar Module “stack” during the coast from the Moon back to Earth, an additional, unplanned, Mid-Course Correction burn, MCC-7, had to be carried out. The damage to the Service Module prevented the use of its 21,900 pounds thrust ( kilonewtons) Aerojet General Service Propulsion System engine. It was necessary to use the LM’s Bell Aerosystems Ascent Propulsion System engine. The APS engine produced 3,500 pounds of thrust ( kilonewtons). The maneuver had to be carried out manually by the astronauts from the LM’s cockpit.
Mission Commander Lovell visually aligned the spacecraft with the LM’s RCS thrusters, by sighting the Earth in his window of the LM. Once aligned, LM pilot Fred Haise conducted the burn, which was timed by CM pilot Jack Swigert.
Swigert timed the burn using his NASA-issued Omega Speedmaster Professional Chronograph, a very accurate manual wristwatch.
The Mid Course Correction ignition commenced at T+137:39:51.5 and the engine was cutoff at T+137:40:13.0 (12:52:51–12:53.13 UTC), for a duration of 21.5 seconds.
MCC-7 was performed at EI-5 hours (137:39 GET). The same manual piloting technique used for MCC-5 was used for control during MCC-7. This was manual crew pitch and roll control with the TTCA and automatic yaw control by the AGS. MCC-7 was performed with LM RCS using the +X translation push button. It steepened the flight path angle at EI to -6.49 degrees. After MCC-7, the crew maneuvered the spacecraft to the SM separation attitude. The CM re-entry RCS system was activated and a firing test of the thrusters was successful. —“Apollo 13 Guidance, Navigation, and Control Challenges” by John L. Goodman, United Space Alliance. American Institute of Astronautics AIAA 2009-6455 at Page 23.
The Omega Speedmaster Professional Chronograph is a manual-winding analog wrist watch produced by Omega, a luxury brand of Société Suisse pour l’Industrie Horlogère, (SSIH) and now a part of the SWATCH Group. The case is made of stainless steel and has a diameter of 48 millimeters (1.89 inches). The Speedmaster Professional, which is also known as the “Moon Watch,” or “Speedy” to watch collectors, features a stop watch function and three sub dials for recording hours, minutes and seconds. The chronograph has a black dial with tritium-painted hands and hour marks. The bezel has a tachymeter for calculating speed based on time. When fully wound, the Speedmaster can run for up to 48 hours. The chronograph is water resistant to a depth of 50 meters (164 feet).
The Speedmaster’s crystal is not glass, but “hesalite,” a clear, scratch-resistant plastic. There had been concern that if a crystal broke during a space flight, glass fragments could be scattered throughout the weightless environment of the spacecraft, presenting a danger to the astronauts.
NASA provided Omega Speedmaster Professional Chronographs to Gemini and Apollo Program astronauts. Each watch was engraved with NASA’s two-digit serial number, and could be equipped with an adjustable length Velcro strap which allowed the watch to be worn on the outside of the space suit. NASA also assigned an equipment part number.
Jack Swigert’s watch, p/n SEB12100039-002, was NASA’s number 69. It is in the collection of the Smithsonian Institution National Air and Space Museum, as Catalog Number 1977-1181.000. In 2016, the watch was on display at the University of Colorado.
16 April 1972: At 17:54:00 UTC (12:54 p.m., Eastern Standard Time), Apollo 16 was launched from Launch Complex 39A at the Kennedy Space Center, Cape Canaveral, Florida. Aboard were Captain John Watts Young, United States Navy, the Mission Commander, on his fourth space flight; Lieutenant Commander Thomas Kenneth Mattingly II, U.S. Navy, Command Module Pilot, who had been scheduled for the Apollo 13 mission; and Lieutenant Colonel Charles Moss Duke, Jr., U.S. Air Force, Lunar Module Pilot. Apollo 16 was the tenth manned Apollo mission, and the fifth to land on The Moon. The landing site was in the Descartes Highlands.
The Saturn V lifted off at T + 000:00:00.59 and quickly accelerated, reaching Mach 1 one minute, 7.5 seconds after launch (T + 01:07.5). The S-IC first stage engines cut off and the stage separated at T + 02:43.5. The S-II stage continued to drive the space craft, and Apollo 16 entered Earth orbit at 18:05:56.21 UTC.
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 (110.642 meters) tall. The first and second stages were 33 feet (10.058 meters) in diameter. Fully loaded and fueled the rocket weighed 6,200,000 pounds (2,812,273 kilograms).¹ It could lift a payload of 260,000 pounds (117,934 kilograms) to Low Earth Orbit.
The first stage was designated Saturn 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, each, for a total of 7,610,000 pounds of thrust at Sea Level. These engines were ignited seven seconds prior to lift off and the outer four burned for 168 seconds. The center engine was shut down after 142 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 Saturn 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, and combined, 1,161,250 pounds of thrust.
The Saturn V third stage was designated Saturn 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 wou 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.
John Young had been a Navy test pilot before being assigned to NASA as an astronaut. He was the pilot for Gemini 3; backup pilot, Gemini 6A; commander, Gemini 10; command module pilot for Apollo 10; backup commander, Apollo 13; and commander, Apollo 16. He retired from the U.S. Navy in 1976 after 25 years of service. He would go on to command the first space shuttle flight, Columbia (STS-1) and then STS-9. He was scheduled to command Atlantis (STS-61-J). John Young retired from NASA in 2004, as one of the world’s most experienced astronauts.
¹ At First Motion (T + 000.00.00.3) the Vehicle Weight of Apollo 16/Saturn V AS-511 was calculated at 6,439,605 pounds (2,920,956 kilograms).
15 April 1970, 01:09:40 UTC: T plus 077:56:40.0: The Apollo 13 Saturn S-IVB-508 third stage impacted the surface of The Moon north of Mare Cognitum. (S. 2° 33′ 00″, W. 27° 52′ 48″)The S-IVB hit the lunar surface at a velocity of 2.58 kilometers per second (5,771 miles per hour). The impact energy was 4.63 x 1017 ergs (1.04 kiloton).
The impact was detected by seismometers placed on the Moon by Apollo 12 astronauts Pete Conrad and Alan Bean. This was part of the Apollo Lunar Surface Experiments Package, or ALSEP.
The Apollo 12 seismometer was located 135 kilometers (83.9 miles) from the Apollo 13 third stage impact. The signals were used to calibrate the instrument package, which was in service from 1969 to 1977.
The Saturn V third stage was designated Saturn 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 (118,841 kilograms). The third stage had one Rocketdyne J-2 engine which used liquid hydrogen and liquid oxygen for propellant. Itproduced 232,250 pounds of thrust (1,033.10 kilonewtons). 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.