The initial plan for the Apollo 13 Lunar Module (LM or LEM) was to land in the Fra Mauro region of the Moon. The Apollo 13 lunar landing mission was abandoned two days after launch on April 13, 1970, when an oxygen tank on the Command and Service Module (CSM) overheated and exploded. Because the CSM could not provide life support, the LM, which was meant to support two men for 45 hours, was used as a lifeboat to house the three astronauts (Commander James A. Lovell Jr., CSM pilot John L. Swigert Jr., and LM pilot Fred W. Haise Jr.) for 90 hours. For the duration of the voyage, energy and water usage were dramatically reduced, and the CM lithium hydroxide cannisters, which were used to scrub carbon dioxide from the air, were converted for use on the LM. The LM descent engine was used to speed the spacecraft around the Moon and back to Earth as the Apollo 13 proceeded on to the Moon. The astronauts returned to the Command Module for reentry after the LM was discarded soon before reaching Earth. The LM re-entered the atmosphere over the southwest Pacific and burned up, with any remaining fragments crashing into the deep ocean off the coast of New Zealand.
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Lunar Module Spacecraft and Subsystems
The lunar module was a two-stage spacecraft that was planned to conduct operations near and on the Moon. The mass of the LM was 15,188 kg, which included crew, expendables, and 10,691 kg of propellants. The LM’s ascent and descent stages worked together until staging, at which point the ascent stage became a single spacecraft for rendezvous and docking with the command and service module (CSM). The descending stage was an octagonal prism 4.2 meters across and 1.7 meters thick that made up the lowest half of the spaceship. The bottom of the descent stage was suspended 1.5 meters above the surface by four landing legs with spherical footpads installed on the sides of the stage. On opposing landing legs, the distance between the ends of the footpads was 9.4 meters. A small astronaut egress platform and ladder were built into one of the legs. From the stage’s bottom, a one-meter-long conical descending engine skirt protruded. The landing rocket, two tanks of aerozine 50 fuel, two tanks of nitrogen tetroxide oxidizer, water, oxygen, and helium tanks, and storage space for lunar equipment and experiments, as well as the lunar rover in the case of Apollo 15, 16, and 17. The fall stage was created to serve as a launch pad for the ascent stage from the Moon.
The climb stage was a 2.8-meter-high, 4.0-by-4.3-meter-wide irregularly shaped unit mounted on top of the fall stage. The astronauts were housed in a 6.65 cubic meter pressurized crew compartment on the ascent stage. On one side, there was an ingress-egress gate, and on top, there was a docking hatch for connecting to the CSM. A parabolic rendezvous radar antenna, a steerable parabolic S-band antenna, and two in-flight VHF antennas were also placed along the top. Above and to either side of the egress hatch were two triangular windows, and four thrust chamber assemblies were positioned around the sidewalls. The ascending engine located at the very bottom of the unit. The stage also had tanks for helium, liquid oxygen, gaseous oxygen, and reaction control fuel, as well as an aerozine 50 fuel and oxidizer tank. In the LM, there were no seats available. A control console was situated above the ingress-egress hatch and between the windows in the front of the crew compartment, with two more control panels mounted on the side walls. At the conclusion of lunar surface operations, the ascent stage was to be launched from the Moon, returning the men to the CSM.
A deep-throttling ablative rocket with a maximum thrust of around 45,000 N was installed on a gimbal ring in the center of the descent stage as the descent engine. The ascension engine was a constant-thrust, fixed-thrust rocket with a thrust of around 15,000 N. The reaction control system, which comprised of four thrust modules, each with four 450 N thrust chambers and nozzles pointing in separate directions, was used to maneuver. The S-band antenna was used for telemetry, TV, voice, and range communications with Earth. The astronauts and the LM, as well as the LM and the circling CSM, communicated through VHF. Both S-band and VHF tranceivers and equipment were redundant. The electronics and cabin were kept at a constant temperature thanks to an environmental management system that regenerated oxygen. Six silver-zinc batteries provided power. A radar ranging system, an inertial measurement unit with gyroscopes and accelerometers, and the Apollo guidance computer provided guidance and navigation control.
What happened to the first lunar lander?
The first crewed vehicle to land on the Moon was the Apollo 11 Lunar Module (LM) “Eagle.” Commander Neil A. Armstrong and LM pilot Edwin E. “Buzz” Aldrin, Jr., the first men to walk on the Moon, were aboard. The Early Apollo Scientific Experiment Package (EASEP), which included many self-contained experiments to be deployed and left on the lunar surface, as well as other scientific and sample collection hardware, was also included on the LM.
Mission Profile
At 17:44:00 UT, the LM separated from the Command/Service Module (CSM). At 18:11:53 UT, Collins began a separation maneuver after a visual check. At 19:08 UT, the LM descent engine ignited for 30 seconds, putting the craft into a descending orbit 14.5 kilometers above the Moon’s surface. The LM descent engine burned for 756.3 seconds at 20:05, signaling the start of descent to the lunar surface. “Houston, Tranquility Base here – the Eagle has landed,” Armstrong reported at 20:17:40 UT (4:17:40 p.m. EDT) on July 20, 1969, in the region known as Mare Tranquilitatis (the Sea of Tranquility) at 0.67416 degrees N latitude, 23.47314 degrees E longitude (as determined from Lunar Reconnaissance Orbiter images, DE 421 mean Earth/polar rotation axis
“That’s one modest stride for man, one huge leap for mankind,” Armstrong said as he stepped onto the lunar surface at 02:56:15 UT on July 21 (10:56:15 p.m. EDT on July 20). He then took a little sample of lunar material as a backup. 19 minutes later, Aldrin arrived, describing the lunar surface as “magnificent desolation.” The astronauts then read aloud the inscription on a plaque installed on a strut below the ladder: “In July 1969, A.D., men from the planet Earth set foot on the Moon for the first time. We came to bring peace to the entire world.” They raised an American flag and spoke with President Nixon over the radio. The astronauts used the EASEP and other instruments to gather 21.55 kg of lunar rock and soil, as well as take photos. The astronauts traveled a total distance of around 250 meters, with both distances ranging from the LM to about 100 meters. They put the lunar samples, as well as the lunar samples and the solar wind experiment, into two core tube samples of lunar soil. After handing the sample boxes to Aldrin and depositing a packet of remembrance objects on the ground, Aldrin returned to the LM first, after 1 hour 41 minutes on the lunar surface. Armstrong followed around 12 minutes later, at 05:09:32 UT. When the LM hatch was closed at 5:11:13 UT, the EVA came to a conclusion. Armstrong and Aldrin rested and checked out systems for the next 7 hours.
After 21 hours and 36 minutes on the lunar surface, the LM blasted off at 17:54:01 UT on July 21. The LM was jettisoned into lunar orbit at 00:01:01 UT on July 22 after docking with the CSM, commanded by Michael Collins, at 21:34:00 UT. The LM’s fate is unknown, however it is believed to have crashed on the lunar surface within the next 1 to 4 months.
The lunar module was a two-stage spacecraft that was planned to conduct operations near and on the Moon. The overall mass of the LM ascent and descent stages, including propellants, was 15103 kg for the spacecraft (fuel and oxidizer). The ascent stage weighed 2445 kg dry and stored 2376 kg of propellant. The dry mass of the descent stage (including stowed surface equipment) was 2034 kg, and there was initially 8248 kg of propellant onboard. The LM’s ascent and descent stages worked together until staging, at which point the ascent stage became a single spacecraft for rendezvous and docking with the command and service module (CSM). The descending stage was an octagonal prism 4.2 meters across and 1.7 meters thick that made up the lowest half of the spaceship. The bottom of the descent stage was suspended 1.5 meters above the surface by four landing legs with spherical footpads installed on the sides of the stage. On opposing landing legs, the distance between the ends of the footpads was 9.4 meters. A small astronaut egress platform and ladder were built into one of the legs. From the stage’s bottom, a one-meter-long conical descending engine skirt protruded. The landing rocket, two tanks of aerozine 50 fuel, two tanks of nitrogen tetroxide oxidizer, water, oxygen, and helium tanks, and storage space for lunar equipment and experiments, as well as the lunar rover in the case of Apollo 15, 16, and 17. The descending stage was abandoned on the Moon after serving as a launch platform for the ascent stage.
The climb stage was a 2.8-meter-high, 4.0-by-4.3-meter-wide irregularly shaped unit mounted on top of the fall stage. The astronauts were housed in a pressurized crew compartment with a volume of 6.65 cubic meters on the ascent stage, which also served as the base of operations for lunar activities. On one side, there was an ingress-egress gate, and on top, there was a docking hatch for connecting to the CSM. A parabolic rendezvous radar antenna, a steerable parabolic S-band antenna, and two in-flight VHF antennas were also placed along the top. Above and to either side of the egress hatch were two triangular windows, and four thrust chamber assemblies were positioned around the sidewalls. The ascending engine located at the very bottom of the unit. The stage also had tanks for helium, liquid oxygen, gaseous oxygen, and reaction control fuel, as well as an aerozine 50 fuel and oxidizer tank. In the LM, there were no seats available. A control console was situated above the ingress-egress hatch and between the windows in the front of the crew compartment, with two more control panels mounted on the side walls. At the conclusion of lunar surface operations, the ascending stage was launched from the Moon, returning the men to the CSM.
Early Apollo Surface Experiments Package (EASEP)
The Early Apollo Surface Experiments Package (EASEP) was a collection of scientific devices that the astronauts put at the Apollo 11 landing site. The ALSEP experiment packages used on following Apollo missions were based on this package. It had two solar panels for power (the EASEP could only operate during lunar day), an antenna and communications system for sending data to Earth ground stations and receiving commands, a passive seismometer for measuring seismic activity and physical properties of the lunar crust and interior, and a lunar dust detector for measuring dust accumulation and radiation damage to solar cells. The seismometer and dust detector were mounted on a square base, together with an isotope heater and a cylindrical antenna pole with an antenna positioning mechanism. The canted rectangular solar panels, positioned to face east and west, were kept in place by two brackets protruding from opposing sides of the base. The unit weighed 48 kg in total. At 2119 MHz, the EASEP received uplink commands and sent telemetry data back to Earth at 2276.5 MHz. Although it was not linked to the unit and required no power, the laser range retroreflector (LRRR) was deemed part of the EASEP. It was placed around 5 meters to the north-west of the EASEP.
The EASEP was placed 17 meters south of the LM, at 0.6735 N latitude and 23.4730 E longitude, and was activated by ground command at 04:40:39 UT on July 21, 1969, while the astronauts were still on the surface. Ground command terminated transmission around 5 hours before local lunar sunset on August 3, 1969, at 10:58:46 UT, when the power began to diminish as predicted. Despite operating temperatures above the projected maximum by 30 degrees Celsius, the EASEP performed as expected. The equipment was turned back on the following lunar day, but on the 27th of August 1969, about noon on the second lunar day, the EASEP stopped accepting commands from Earth stations, and the experiment was ended.
Is the Aquarius Lem still orbiting the Earth?
The lunar modules’ ascending stages were also employed for seismology. The now useless spacecraft was discarded and ordered by Mission Control to crash the Moon’s surface at a precise spot near an ALSE after the lunar landing crew had transferred everything coming back to Earth from the lunar module and closed it out. One of these carefully orchestrated wrecks yielded some startlingly bizarre effects. The shock wave from Apollo 12’s lunar module Intrepid slamming with the lunar surface vibrated through the Moon for more than 55 minutes. The continuous propagation of the wave was subsequently attributed to the Moon’s dryness, as dry rocks did not damper the waves as effectively as they do on Earth.
Apollo 9, Apollo 10, and Apollo 13 were the three outliers. The lunar module of Apollo 9 burned up in the Earth’s atmosphere because it was an Earth orbital mission. Snoopy, the lunar module of Apollo 10, was launched into solar orbit and remains there today. On the way back to Earth, Apollo 13 used their lunar module Aquarius as a lifeboat, allowing it to burn up in the atmosphere during reentry.
Is the service module from Apollo 13 still in space?
The Apollo 13 mission was supposed to be the third to take humans to the Moon’s surface, but an explosion of one of the oxygen tanks and the subsequent damage to other systems forced the mission to be canceled before the planned lunar landing could take place. On April 17, 1970, the crew, which included commander James A. Lovell, Jr., command module pilot John L. Swigert, Jr., and lunar module pilot Fred W. Haise Jr., returned safely to Earth.
On April 11, 1970, at 19:13:00 UT (02:13:00 p.m. EST), Apollo 13 was launched from pad 39A at Kennedy Space Center on the Saturn V SA-508. The center engine of the S-II stage cut out 132 seconds early during second stage boost, causing the other four engines to burn 34 seconds longer than normal. Because the velocity after the S-II burn was still 68 m/sec lower than expected, the S-IVB orbital insertion burn at 19:25:40 took 9 seconds longer than expected. At 21:54:47 UT, CSM/S-IVB separation occurred at 22:19:39 UT, and CSM-LM docking occurred at 22:32:09 UT. The S-IVB auxilliary propulsion system burned for 217 seconds at 01:13 UT on April 12 to put the spacecraft on a lunar impact trajectory. (On 14 April at 01:09:41.0 UTC, it collided with the lunar surface at 2.75 S, 27.86 W, at a velocity of 2.58 km/s and a 76-degree angle from horizontal.) On April 13, at 01:27 UT, a 3.4 second mid-course adjustment was made.
On 14 April, from 02:24 to 02:59 UT, a television broadcast was produced from Apollo 13, and a few minutes later, at 03:06:18 UT. Jack Swigert activated the fans in the service module’s oxygen tanks 1 and 2. The Accident Review Board determined that cables in oxygen tank no. 2 that had been broken during pre-flight testing shorted, causing the teflon insulation to catch fire. The fire spread throughout the tank, increasing the pressure until it detonated at 3:07:53 UT on 14 April (10:07:53 EST 13 April; 55:54:53 mission elapsed time), damaging oxygen tank no. 1 and the interior of the service module, as well as blowing off the bay no. 4 roof. Because the command module’s oxygen supply were expended, the mission had to be cancelled, and the crew was transferred to the lunar module and the command module was powered down.
At 08:43 UT, the lunar module descent propulsion system (LMDPS) performed a mid-course maneuver (11.6 m/s delta V) to position the spacecraft on a free-return trajectory that would carry it around the Moon and back to Earth, with a target of the Indian Ocean at 03:13 UT 18 April. A second LMDPS burn at 02:40:39 UT 15 April for 263.4 seconds produced a differential velocity of 262 m/s, reducing the predicted return time to 18:06 UT 17 April with splashdown in the mid-Pacific. The lunar module was powered down except for environmental control, communications, and telemetry to save power and other consumables, and passive thermal control was developed. A 15 second LMDPS burn at 10% throttle at 04:32 UT on April 16 resulted in a 2.3 m/s velocity drop and a -6.52 degree entrance flight path angle. After that, the team began to partially power up the CSM. The flight path entrance angle was -6.49 degrees after a 22.4 second LMDPS burn on April 17 at 12:53 UT.
The crew photographed the damage after the service module, which had been kept linked to the command module to preserve the heat shield, was ejected on 17 April at 13:15:06 UT. At 16:43:02 UT, the command module was started up and the lunar module was jettisoned. Any pieces of the lunar module that survived atmospheric re-entry, including the SNAP-27 generator, which contained 3.9 kg of plutonium and was intended to power the ALSEP device on the lunar surface, crashed into the Pacific Ocean northeast of New Zealand. After a mission that lasted 142 hours, 54 minutes, and 41 seconds, Apollo 13 splashed down in the Pacific Ocean on April 17, 1970, at 18:07:41 UT (1:07:41 p.m. EST). The splashdown occurred at 21 degrees 38 minutes south latitude, 165 degrees 22 minutes west latitude, southeast of American Samoa, and 6.5 kilometers (4 miles) from the recovery ship USS Iwo Jima.
The Apollo H-series spacecraft was the second in the series. The mission’s goals were to (1) explore the moon’s hilly upland Fra Mauro region, (2) conduct selenological inspection, survey, and sampling of material in the Fra Mauro formation, (3) deploy and activate an Apollo lunar surface experiments package (ALSEP), (4) further develop man’s capability to work in the lunar environment, and (5) obtain photographs of potential lunar exploration sites. These objectives were to be accomplished from a near-circular lunar orbit and on the lunar surface at 3 degrees south latitude and 17 degrees west longitude. Despite the fact that the mission’s planned objectives were not met, a limited amount of photographic data was gathered. Haise and Swigert were both civilians on their first spaceflights, while Lovell was a Navy captain on his fourth spaceflight (he’d previously flown on Gemini 7, Gemini 12, and Apollo 8). John Young, Charles Duke, and John Swigert were the backup crew (who replaced Thomas Mattingly on the prime crew after the crew was exposed to German measles). The Apollo 13 Command Module “Odyssey” is now on display in Hutchinson, Kansas’ Kansas Cosmosphere and Space Center. It was first seen at the Musee de l’Air in Paris, France.
Spacecraft and Subsystems
The Command and Service Module (CSM) was made up of two separate units: the Command Module (CM), which housed the crew, spacecraft operations systems, and re-entry equipment, and the Service Module (SM), which carried the majority of the consumables (oxygen, water, helium, fuel cells, and fuel) as well as the main propulsion system. The two coupled modules had a total length of 11.0 meters and a maximum diameter of 3.9 meters. All of the crewed Apollo missions used Block II CSMs. The launch mass of the Apollo 13 CSM was 28,881 kilograms, including propellants and expendables, with the Command Module (CM 109) weighing 5703 kg and the Service Module (SM 109) weighing 23,178 kg.
For communications between astronauts, CM, LM, and Earth, telecommunications included voice, television, data, and tracking and ranging subsystems. An S-band uplink and downlink system provided voice interaction. A uniform S-band transponder was used to track the satellites. At the SM’s aft end, a high gain steerable S-band antenna with four 79-cm diameter parabolic dishes was installed on a folding boom. The SM was also equipped with two VHF scimitar antennas. A VHF recovery beacon was also installed in the CM. The cabin atmosphere, pressure, temperature, carbon dioxide, scents, particulates, and ventilation were all managed by the CSM environmental control system, which also controlled the temperature range of the electronic equipment.
Command Module
The CM was a 3.65-meter-high conical pressure vessel with a maximum diameter of 3.9 meters at its base. It was constructed from an aluminum honeycomb sandwiched between sheets of aluminum alloy. The CM’s base was made up of a heat shield constructed of brazed stainless steel honeycomb that was filled with phenolic epoxy resin as an ablative substance and ranged in thickness from 1.8 to 6.9 cm. The hatch and docking system at the apex of the cone was meant to mate with the lunar module. Three chambers were created in the CM. The three 25.4 m diameter main parachutes, two 5 m drogue parachutes, and pilot mortar chutes for Earth landing were stored in the forward compartment of the cone’s snout. Propeller tanks, reaction control engines, wiring, and plumbing were all housed in the aft compartment, which was located around the base of the CM. The crew compartment took up the majority of the CM’s volume, with 6.17 cubic meters of space. In the center of the compartment, three astronaut couches were lined up facing forward. Above the middle couch, there was a big access hatch. The docking hatch in the CM nose was reached through a small access tunnel. The astronauts’ controls, displays, navigation devices, and other systems were kept in the crew compartment. The CM had five windows: one in the access door, one in each of the two outer seats next to each astronaut, and two forward-facing rendezvous windows. After the CM and SM separated, five silver/zinc-oxide batteries provided power: three for re-entry and landing, and two for vehicle separation and parachute deployment. Twelve 420 N nitrogen tetroxide/hydrazine reaction control thrusters were installed aboard the CM. After the mission’s separation from the Service Module, the CM provided re-entry capabilities.