Apollo 11 - Man on the Moon: Flight Summary

Haim Mazar followed the manned flights in the Apollo series in real time as a teenager. Today, 43 years later, we bring the words as he wrote with the return of Apollo 11. This is an article from a large series of articles covering all manned flights up to 1974.

introduction

The man on the moon, this is how the Apollo 11 operation should be defined, this operation which should be considered a turning point in the history of the human species, which began on July 16.7.1969, 23.7 and ended on July XNUMX. The crew that participated in the flight included Neil Armstrong, Edwin Aldrin and Michael Collins. This operation, which was the first of its kind, included many dangers, the unknown part of which was greater than the known, for the reason that what was done on the moon was less known at this time than what was known about the structure of its surface. Because of this, a number of alternatives were prepared for the flight, in case it turned out that landing on the moon would be impossible.

A. A fault in an earthly orbit - the astronauts would try to fix the fault themselves. If it turned out that they were unable to continue towards the moon, they would go on a 10-day round trip around the Earth. For this purpose, they were provided with a full program of operations designed to test a prolonged stay in space close to the Earth. According to this plan, Apollo 11 would have been transformed from a lunar vehicle into a space laboratory.

B. If it had become clear during the flight to the moon that the landing was impossible, the astronauts would have circled the moon and returned to Earth, without taking any risks of an unsafe landing on the moon.

The US space agency has prepared crews as well as rockets and spacecraft for additional landing attempts in the event of a landing failure. Two such attempts using the Apollo 12 and Apollo 13 spacecraft could have been conducted as early as 1969.

16.7- the first day of the flight

11 minutes after launch, the spacecraft entered an Earth orbit that is 184 km from Earth. At this altitude, the spaceship circled the Earth in 45 to XNUMX hours and XNUMX minutes. During this period of time when the spacecraft was near the Earth, all its systems were tested. When the spacecraft's systems were found to be working, the spacecraft was detached from its terrestrial orbit and moved to a lunar flight path. In the next step, a docking maneuver was performed with the lander and the third stage of the missile was launched into a solar orbit. The route correction was canceled as it was found to be accurate. On this day there were several small but insignificant glitches.

1. In the first hours of the flight, the astronauts announced a certain malfunction in the measuring devices. The atmosphere in the spaceship reached complete oxygen saturation when the measuring instruments did not show it.

2. Problems with a leaking drinking water tank.

3. When the spaceship detached itself from the third stage and turned on its axis to remove the lander from it, the radio and television connection was cut off for several minutes. Only after the seventh call from the control center was Michael Collins' voice heard again. Collins' explanation was that the distance between the spacecraft and the rocket stage was greater than planned. The result is non-directional antennas. Because of this, the first television broadcast was not held. A fifteen-hour broadcast was made from the antennas.

In order to prevent overheating of the spacecraft during the flight, it was transferred to a new flight mode while flying to the moon, the spacecraft rotated around an axis.

Armstrong, Aldrin and Collins, for whom this is their second flight in space, were calmer than in their first flights. Heartbeats were much slower than on their first flights as part of Operation Gemini. This is despite the enormous acceleration that the first stage of the Saturn rocket gave them. They showed unusual self-control. They avoided the words of admiration that characterized similar space operations and contented themselves with short technical comments, but full of self-confidence.

17.7- the second day for the flight

On this day they worked 14 hours and rested 10 hours. During those hours they worked, they made a course correction and for that they turned on the engine for 2.19 seconds. Engage in stargazing and navigational exercises. Before lying down to sleep they did gymnastics. One of the exercises was running in place. On this day, unlike the previous day, they showed excitement.

18.7-the third day of the flight

A 25-minute color TV broadcast was conducted. Aldrin followed by Armstrong moved to the lander to check its systems. They stayed there for 3 hours. We sleep for 10 hours - an hour and a half more than planned

19.7 - The fourth day of the flight

The flight path was found to be normal and due to everything its repair was cancelled. Thanks to this, the astronauts could extend their sleep and indeed they slept 9 hours. They fell asleep an hour late, because they had a little trouble correcting the movement of the spaceship around itself.

That day they saw a solar eclipse. They saw the aura of the sun in all its glory. Since it was dark they also saw the stars. The spacecraft was filled with sunlight reflected from Earth to such an extent that you could read a book.

The spacecraft entered lunar orbit when the first of its laps began on the far side of the moon. Because of this, the connection was lost, but it was restored 36 minutes later. The spacecraft entered an elliptical orbit whose distances from the moon varied between 111-314.5 km. All this while the speed is reduced from 9200 km/h to 6100 km/h. After that, the route was changed to a route whose distances from the moon ranged between 100-125 km. Since the strength of the moon's gravity is not equal along the entire orbit, the orbit was balanced, so that its distance from the moon was 109 km.

Shortly after the spacecraft entered its lunar orbit, Armstrong saw two strange spectacles. He said that the moon appeared to be a gray color that gradually brightened as the spacecraft approached the lunar day zone. Where the sun is directly above the surface of the moon, the ground appeared brown and in some places even reddish brown in color.

In the first lap, the astronauts examined the Sea of ​​Tranquility where they later landed. In the second round, a 15-minute TV broadcast was held. Armstrong said that to the north of Aristarchus Crater there is an area that is much brighter than its surroundings and is somewhat luminous.

20-21.7 the fifth day and the sixth day for the flight

On the 10th lap of the moon, Armstrong moved from the command cabin to the lander (the command cabin was given a new name before the flight - Columbia after Christopher Columbus discovers the American continent) to the lander (the lander was also given a new name Eagle - after the bird that symbolizes the nation's beliefs and aspirations the American). An hour and 33 minutes later, Aldrin transferred to the lander. Michael Collins was left alone in the control room. Armstrong and Aldrin stayed on the landing until the 13th lap. At this time they checked the lander for a final check before landing and transferred all the equipment necessary for landing to it.

On the 13th lap, Armstrong pressed a switch that pulled out the landing gear. Then he disconnected her from the command room and moved her to a distance of 20 meters. When the lander reached this distance from the command cabin, Armstrong activated the stabilization engines to prevent it from shaking, something that contained many dangers. The main one being the inability to maintain a constant course and distance from the moon. The word means crash on the surface of the moon. The two spaceships were found in this state for about an hour and a half. At that time, Collins conducted a visual inspection of the lander. After the lander had passed 80% of the orbit, it lowered it and circled the moon at a distance of 15 km from its face for an hour.

Two and a half hours after separation, the lander was found 15 km from the surface of the moon. This distance was reduced to 13 km. From this height the lander fell freely up to a height of 6.5 km. At an altitude of 10.35 km the computer stopped working properly. The alarm signals were accompanied by numbers that the astronauts did not encounter during their training, so the treatment methods were unknown. The disruptions were probably due to too much load on the computer. The control center told the astronauts that they could ignore the alarms and continue their descent towards the moon.

The computer made two different series of calculations. He continuously calculated the changing height of the lander above the lunar surface and the rate of its descent towards the moon based on signals he received from the landing radar fixed on the lander's belly. At the same time he also calculated the distance between the lander and the command cabin and the direction in which the lander would have to fly, if for any reason an emergency situation developed and Armstrong would have had to fly the lander to an immediate meeting with the command cabin. A second radar device mounted on top of the lander followed the command cabin, which hovered about 100 km above it, providing the computer with the information for the second series of calculations.

The computer informed the astronauts of the fact that its systems were overloaded and the immediate danger was that the electronic device would decide to cancel all the data it had received up to that moment and start a new series of calculations, despite the fact that the lander was getting closer to landing. Armstrong knew that if this did happen, he would have no choice but to activate the lander's ascent stage engine, return and climb into lunar orbit.

At the time, Stephen Bayliss was sitting at the control panel of the guidance officer at the control center in Houston. He made a quick assessment of the situation and gave the team a proposal to solve the problem: "Don't require the computer to display the landing data on the lander's control panel." Instead this data was transmitted to the control center.

At a distance of 6.5 km from the surface of the moon, the braking engine was activated and the lander descended slowly to a height of 150 meters. From this altitude the lander switched to manual steering with Armstrong holding the rudder. At a height of several meters, Armstrong noticed that the area intended for landing was littered with craters and rocks. Therefore, he copied the landing to another site 6.5 km away from the original site. This possibility has been taken into account. The search of the new site took 37 seconds longer than planned. Due to this, Delek remained in the landing for 40 seconds hovering instead of 114 which should have remained according to the plan. The astronauts were very close to starting the ascent engines to return to the command cabin. Despite the lack of fuel, it was decided to land.

In the last seconds of the descent before the moon, the engine kicked up a large amount of dust. The dust flew in all directions at the same time before the moon and remained in space for a long time. He was quite far from the astronauts. Its transparency allowed them to see the scenery, but its motion made it difficult to determine the most suitable speed for a smooth landing. It was like landing a fast moving car in the fog.

During the landing, the rudders and engines were activated automatically through a system connected to a radar device that precisely determined the height, angle, landing speed and power of the engines. Only at the last stage, a few seconds before landing, Armstrong held the rudders in his hands and landed the lander on the soft landing pads.

If an engine malfunction were discovered, the astronauts would abort their approach to the moon by abandoning the lower section and firing the launch engine to return to lunar orbit. This would be done if there was a malfunction in the landing engine, or another vital system, or if the landing area seemed too difficult to land there safely. This maneuver is only possible from a height of 30 meters. There is always the possibility that the landing gear will fail at too little altitude to allow landing. In such a case the lander would crash or make a hard landing that could damage it and possibly cause the crew to get stuck on the surface of the moon. It must be remembered that the amount of oxygen and food was enough for them for only 24 hours.

Another possibility is that one of the lander's legs would have settled on a rock or depression in such a way that the lander was tilted too much for a safe jump. In this regard, the engineers said that due to the small gravity of the moon, the lander could safely launch even if it was tilted on its side at an angle of 30 °. The landing was a little south of the target. But she kept the east-west line. The lander rests on the ground at an angle of 4°.

During the landing there was a small malfunction. Moisture rose in one of the fuel lines of the engine that was started during the descent before the moon. This malfunction is not serious because the lander is able to withstand greater humidity during landing.

At that time, Armstrong's heart rate increased to 156 per minute. After landing, the heart rate returned to 90 per minute.

The wireless connection between the astronauts inside the lander after landing and between the ground stations changed from time to time from good to weak and back again.

Collins said that he did not see the lander and asked for instructions from the control center. After some time he announced that according to the instructions he had found the lander. It turned out that the automated system had misled him into looking for the lander in the wrong place.

Like his friends, Collins also prepared for emergencies. Collins knew that in an emergency he would have to save his friends. To make it easier for himself and his friends, he removed the middle bunk and created a passage in the middle of the cabin.

During the period of time Aldrin and Armstrong were on the moon (21 hours and 36 minutes), Collins slept only about 5 hours.

The landing date was planned for a time when the sun would be on the moon's horizon so that long shadows of mountains, hills and even stones would be seen on its surface. These shadows made it easier for the astronauts to find the landing site. If they were, unexpected dangers would have been discovered in advance.

On the 15th lap the connection was lost. It turned out that this was due to the discharge of a battery in the control center.

Immediately after landing, Armstrong and Aldrin thoroughly checked all systems to make sure that the landing was ready for an immediate takeoff. The main activity here was protecting the thrust tanks from the heat to prevent explosion. This activity lasted 12 minutes. The astronauts prepared the computer for the jump and conducted a series of tests and observations from the lander to find out if there was an unpleasant surprise waiting for them outside. At the end of the test, which lasted 3 hours, the astronauts ate and prepared themselves for departure.

It turned out that there was a delay in the schedule. This lag was due to an abundance of small details. The astronauts were surprised that it took them a long time to depressurize the lander. The delay may have been due to the radios on their backs. The astronauts emitted gases and they had to be removed to balance the pressure. Delays were also caused in the operation of the measuring devices attached to them.

The astronauts accompanied their work with descriptions of the lunar landscape. Armstrong said that they had no difficulties whatsoever when they went from a state of weightlessness to a state where they felt the gravitational pull of the moon. He said that near the landing there are a large number of craters whose diameter ranges from 1.5-16 meters and "thousands of smaller craters" are added. Some stones that were probably broken by the fire of the braking engine were seen with a dark gray tint on their inner side. According to Armstrong, they are similar in Maran to basalt rocks on Earth. Aldrin said that the color of the rocks changes according to the viewing angle of the viewer. He explained that this is due to the special effect of the lighting on the surface of the moon. This effect creates the illusion of color changes. When a person looks towards the sun, the surface of the moon appears light brown. From another angle they look darker while looking down they look almost black. Moon dust looks very dark. black or gray It is mostly fine like flour, but sprinkled here and there with larger grains.

Armstrong said that something went wrong and shows the time that has passed since the launch.

After the multiple preparations, the astronauts had to rest for about 4 hours. They couldn't fall asleep and shortened the stay on the lander by 35 minutes. They ate another meal, put on the space suits, lowered the air pressure in the cabin, opened the door and left.

The descent to the ground was televised live from the moon to the earth. The television camera that was attached to the side of the lander first aimed at the ladder where the astronauts descended from the lander to the lunar surface. The camera was then placed by Armstrong on a tripod 10 meters from the lander.

Armstrong was the first to go down and about 20 minutes after him Aldrin went down. When Armstrong came down and his left leg is shown on the surface of the moon while his right leg is placed in the "plate" at the bottom of the lander's leg he said: "One small step for man, one big step for humanity". After that he collected a number of stones and put them in the pocket of his pants so that he would have some kind of sample from the face of the moon in case they had to leave the moon for an unexpected reason. The astronauts announced that they were leaving traces on the surface of the moon at a depth of 2.5. cm. There was a thicker layer of soil at the ends of the small depressions and their shoes sank 7.5-10 cm. As a result, their shoes tended to slip to the side when covered in a thick layer. Therefore, they tended to bypass these sockets as much as possible. The dirt on the surface of the moon is very stable and can be piled on a slope of 70°. At first, Armstrong did not remember that he had to immediately collect a number of stones and the control center had to remind him of this. Aldrin said that all the stones are coated with fine dust and that he found among others a crimson colored stone. Many of the stones and rocks, Aldrin said, are covered in bubbles and look like they came from volcanic activity.

Taking the stones was not the first action. She was preceded by a tour around the landing. From this tour it became clear that the engine did not create a muzzle during landing. Before Armstrong collected the first sample he took a series of pictures. One of the rolls of film fell out of the camera and fell to the bottom of the ladder of the "Eagle". Armstrong managed to lean on the landing gear without difficulty. bend down and pick up the cylinder. He said that it was difficult for him to bend down to collect the samples. Aldrin guided him and finally Armstrong announced that he had the first sample.

With the end of the tour around the landing and taking of the stones came the scientific activity which included placing various instruments on the lunar surface.

1. Aldrin placed a highly sensitive passive seismograph on the surface of the moon to know if the moon is active. The tuners in the control center picked up the shocks that the seismograph picked up from Aldrin's footsteps as he moved away from him.

The seismograph was connected to a radio device and automatically transmitted its findings to Earth. The entire device weighed 45 kg and could be activated by radio transmission from Earth. Basically, this device is made of hanging weights that hold a rod that sticks vertically between them. When the device is standing on the surface of the moon, the rod sticks out from its center. If the device is shaken by vibrations, the rod moves like a switch. of a clock. along with the fluctuations. The movement is picked up by the transmitter and transmitted to Earth. The seismograph was equipped with solar collectors that activated it during the day and an isotope device to heat it at night. The isotope device is powered by a tiny amount of plutonium 238 which produces very low radiation and is contained in a container that ensures that the radiation will not be distributed around the device. The seismograph operated for 21 days.

The discovery of lunar activity by these future measurements would help scientists determine the density of the lunar soil and its other properties, the existence of minerals on the moon, its origin and history. The importance of this information lies in the ability to give researchers a more objective possibility to understand the history of the Earth and perhaps of the entire universe.

2. Armstrong placed a mirror consisting of 100 slices of quartz polished in such a way that they return light rays to their source. This device was used to return laser beams sent to it from the Earth and allowed measurement of the distance between these stars with a deviation of only 15 cm. The weight of the device is 39 kg.

3. Aldrin placed on the surface of the moon a rod with an aluminum leaf designed to absorb particles from the sun. Mainly energetic gases such as helium, neon, argon and krypton. This device, which weighed 5 kg, was returned to the lander at the end of the tour on the moon to perform a chemical analysis on it. The device was funded by the Swiss government.

4. After placing the devices, the astronauts took special work tools, including an aluminum awl, a hammer and a hammer. Using these tools they collected samples of soil and rocks into containers that were immediately sealed. In total, they collected 36 kg of lunar soil.

When the soil was removed, the lunar soil, despite its softness, was found to have resistance at a depth of several centimeters and is gradually hardened at a depth of 12.5-15 cm. The resistance comes from below and not from the sides. It is a fact that during the mining the devices moved in the ground from side to side.

The astronauts noticed a similar movement when they tried to drive the flagpole into the ground. Because of this, they had to constantly hold the upper end of the tube of the device designed to collect samples from the lunar surface while driving it with hammer blows. The hammer missed its target several times. This is not caused by poor visibility. While operating the hammer, both body movement and balance were violated. Since the astronauts bent over and leaned on the device, when swinging the hammer with one hand upset the balance, the other hand holding the tube would move almost automatically and the hammer would miss its target. The material that is extracted by the devices appears to be somewhat salty. It really sticks to your hands.

The light bothered them sometimes. When the light rays would hit the helmets from the side, they would penetrate through the face portholes and create a glow that was reflected from all sides. When they entered the shade, their faces would be seen in front of the helmets and the view would blur. When they entered the shade, about 20 seconds would pass before the pupils dilated and it was possible for them to see properly.

Aldrin said that in the shadow there is a mental feeling that he is cold. Although the scientific activity that was planned is very important and should not be underestimated, there was something missing, some kind of act that would be used for future generations and for this purpose a number of actions with symbolic meaning were done.

1. A kind of monument was placed on the moon with the following words engraved on it: "Here people from planet Earth placed their foot on the moon. July 1969. We appealed to the peace of all mankind."

2. Medals in memory of the Apollo 1 pilots: Edward Witt, Virgil Grissom and Roger Chaffee and in memory of the Russian cosmonauts Yuri Gagarin and Vladimir Komarov.

3. The plaque bearing the greetings of 79 heads of state for the Apollo 11 operation.

4. A plaque bearing the names of the Apollo 11 pilots and the name of the President of the United States Richard Nixon.

5. The flag of the United States.

The gait of the astronauts more than once resembled skipping, especially when they said that because of the fine dust the stones were slippery. Armstrong said that they must move and lean forward in the direction they want to go, "otherwise you have the feeling that you are drunk".

Armstrong stayed on the surface of the moon two hours and 14 minutes and a quarter of an hour longer than planned. Aldrin went up to the lander before him. He stayed on the surface of the moon for one hour and 33 minutes. Before boarding the lander, Aldrin loaded the soil samples using a small cargo lift. Both were freed from their backpacks and various accessories that were no longer needed - the used urine containers were thrown onto the lunar soil. The shovels and trowels with which they dug, a television camera and a smaller camera were also left there. This is to reduce the weight of the landing gear and thereby make it easier to take off. Later it turned out that they used only half of the amount of oxygen and a third of the amount of water they had.

In his tour, Armstrong moved away to a distance of 60 meters from the lander. He returned to the landing and locked the door. The connection between the lander and the control center was lost for a little while. From the resumption of contact, the astronauts announced that they were raising the oxygen pressure and everything was fine. As the pressure increased, a pungent smell was felt in the control room. Until takeoff, they stayed in the lander for 12 hours and 9 minutes. They ate and then tried to fall asleep but failed. They woke up, fell asleep and during the entire time you were on the landing until take off they only slept for an hour and a quarter.

The space scientists predicted this situation in advance and explained it both due to the mental state of the astronauts after the lunar tour and due to the existing data on the moon. There was an intense cold that 3 hours later became unbearable. They tried to reduce the operation of the cooling mechanism in the spacesuits to a minimum, but it did not help. Lowered the temperature regulator in the oxygen system to the minimum and that didn't help either. They could raise the blinds and let the light into their faces to warm them, but that would ruin their chances of falling asleep.

The connection with the lander was made in several stages:

1. Detachment of the lower class landing by 28 explosions.

2. Starting the jump engine for 7 minutes and 18 seconds. Thanks to this, the lander rose in less than a minute to a height of 800 meters and moved on an upward slope at a speed of 800 km/h

3. 3 minutes later, the lander was found at an altitude of 4 km and moving at a speed of 3000 km/h. If the engine stopped after 6 minutes, the astronauts could use the navigation rockets to bring themselves up to the command cabin. If the engine had not been running for at least 6 minutes, the navigation rockets would not have been enough to complete the distance and the lander would have crashed on the surface of the moon. If the lander entered a lower orbit than planned, Collins could lower the command cabin to rendezvous with them.

4. 20 minutes after the launch, contact was made between the two spaceships. At this time, the lander moved to the hidden side of the moon in an elliptical orbit whose distances from the surface of the moon ranged from 16.8-87.3 km. Here Armstrong performed another maneuver to approach the control cabin. He increased the speed of the landing by an additional 50 km/h and thereby increased the route, to the route parallel to that of the command cabin. Now the distance between the two routes was only 24 km.

5. From the lander's departure from the hidden side of the moon, Armstrong activated a small navigation jet that increased the lander's speed by an additional 13 km/h. Thanks to this, both spacecraft flew in the same orbit. The distance between them was reduced to 80 km. Now the two spaceships were moving at the same speed - 100 km/h. The navigation jets on the lander were activated again and moved it into a position where it and the command cabin were flying opposite each other. This is how the two spacecraft continued for the entire time they were on the hidden side of the moon. Since the resumption of contact with Israel, the distance between them was less than 6 meters. A few minutes later they connected. During the connection, a strong jolt was felt in both spacecraft. From the moment when the distance between them was reduced to 10 meters, the command passed to Collins.

The rendezvous and docking of the spacecraft was delayed by 3 minutes due to the fatigue of Armstrong and Aldrin and due to the complicated maneuvers required for the spacecraft to dock in orbital flight.

In the jump from the moon, Armstrong's heart rate increased to 90 beats per minute and Aldrin's to 120. A quarter of an hour later, both of them had their heartbeats back to 80.

After docking, Collins cleared the tunnel, removed the door and the lander's docking lug. He then entered the tunnel and helped his friends move the equipment to the control room. Collins removed the empty lithium tanks used to purify the air to make room for the soil samples. After that, Armstrong and Aldrin moved to the control room.

The main cooling system on the lander was shut down to check how long it would remain operational without cooling. In the control center in Houston they assumed that the systems would operate for no more than one hour. From the data received from the lander (at the time the two spacecraft were moving separately, one on its way to the Earth and the other around the Moon). It turned out that only after 4 hours the systems started to stop their activity. This experience proved that rescuing crews in cases of paralyzed spacecraft is possible.

The astronauts turned on the service compartment's engine for 149 seconds. The speed of the spacecraft increased from 5600 km/h to 9100 km/h. The spacecraft moves in an arcuate path to Earth. While on this path, about two hours before separation from lunar orbit, the astronauts disconnected the lander from the command cabin and abandoned it in lunar orbit.

22.7/XNUMX- the seventh day of the flight

The astronauts sleep 10 hours. When they woke up, they found out that the connection between them and the Earth was cut off for 40 minutes. When the relationship was over, a 17-minute television broadcast was held. The route correction for this day has been cancelled.

23.7/XNUMX- The eighth day of the flight

The route correction for this day has been cancelled. The astronauts sleep 10 hours. Near the entrance to the atmosphere, the toilet cabin was disconnected from the command cabin. The command cabin landed near the Hawaiian Islands at a distance of 400 km from the planned landing site. The reason for the change of landing place is a lightning storm. Apollo 11 made its journey in 195 hours and 18 minutes.

after landing

On the same day they landed, the astronauts were transferred to 21 days of isolation in the "Lunar Reception Laboratory". During their isolation, the astronauts underwent a very thorough medical examination. Despite all the concerns, they did not bring any bacteria with them from the moon. The astronauts were found safe and sound. 3 weeks after they entered the "Lunar Reception Laboratory", 5 hours before the time on 12.8 they were released from their medical isolation.