A series of failures clouded the first US attempts to launch spacecraft into a crash orbit or the moon's orbit * This episode deals with the very first years of the US space program
introduction
The United States began its lunar research with the launch of Pioneer spacecraft to the moon. All launches failed. The source of the malfunctions was in the launchers themselves. Learning lessons was required which, in the end, produced many successes one after the other. It is likely that the source of the malfunctions was due to the fact that this was the first plant of its kind and it had to be matured in preparation for the continuation. Until then, the United States did not have any experience in this field, nor could it have any.
Pioneer 0
On May 17, 1958, the United States launched the Pioneer spacecraft using the Thor-Abel launcher. The weight of the launcher is 52 tons. The goal was to hit the moon. 77 seconds after the launch at an altitude of 7 km, the launcher exploded and burst into flames.
Pioneer 1
On October 11, 1958, Pioneer 1 was launched in order to circle the moon and photograph its hidden side. The launch was made using the Thor-Abel launcher. The weight of the launcher is 47 tons. The weight of the spacecraft is 38 kg, of which 14 kg is the weight of research instruments. The diameter of the spacecraft was 74 cm. A radio signal from the control center was supposed to activate the braking engines and put the spacecraft into orbit around the moon. Due to a malfunction in the disconnection mechanism between the spacecraft and the third stage to which it was attached, the plan failed. This malfunction meant that the spacecraft could not reach the speed necessary to reach the moon. The spacecraft reached a distance of 114,750 km from Earth, turned back and burned up in the atmosphere. In total, Pioneer spent 43 hours and 17 minutes in space.
Pioneer 2
Pioneer 2 was designed and built on the model of its predecessors and was supposed to hit the moon. The launcher was Thor-Abel. The launch was on November 8, 1958. The weight of the spacecraft was 39.5 kg. The first two stages of the launcher worked properly. The third stage did not ignite due to a fault in the ignition mechanism. The spacecraft returned and burned up in the atmosphere. The spacecraft reached an altitude of 1,550 km and fell into the Pacific Ocean 42.4 minutes after launch.
Pioneer 3
The spacecraft was launched on December 6, 1958 to hit the moon. The spacecraft weighed 6 kg and was launched using the Yuno 2 launcher. The first two stages increased the speed of the spacecraft to 38,000 km/h. In the first stage, there was a technical fault due to too rapid lowering of the valve that directs the flow of fuel to the combustion chamber. The duration of the burn in the first stage of the launcher was extended from 157 seconds to 180 seconds. The result was a delay in the ignition of the third stage and a deviation of three degrees from the planned flight path. It was clear that the spacecraft would not reach the moon.
The spacecraft traveled 107,270 km, turned around, came back and burned up in the atmosphere. Pioneer 3 spent a total of 38.1 hours in space. Two Geiger counters on the spacecraft picked up valuable details on the second Van Allen strip. These data were used by the astronomers in refining the map of these radiation bands.
Pioneer 4
On March 3, 1959, Pioneer 4 was launched. Unlike its predecessors, it was not designed to hit the moon, but to pass within 24,000 km of it. The goal was to collect data on its magnetic field. The weight of the spacecraft was 5.9 kg. Among the devices were two Geiger counters and a transmitter whose transmissions were received very clearly even at a distance of 640,000 km from the earth. The launcher was Juno 2. The spacecraft deviated from its orbit by 60,000 km due to a fault and entered an orbit around the sun, which is 150 million km away and the orbit lasted 392 days.
Pioneer P-3
On November 26, 1959, the spacecraft was launched with the aim of entering orbit around the moon and photographing its hidden side. 45 seconds after launch, the launcher and spacecraft exploded. The launcher was Thor-Abel and it was hypothesized that it malfunctioned. The launcher and spacecraft apparently fell into the Atlantic Ocean.
Pioneer 30 – P
On September 25, 1960, the spacecraft was launched with the aim of entering orbit around the moon by the Atlas-Abel launcher, the upper stages being too weak resulted in the failure of the launch. The spacecraft weighed 175 kg. 10 minutes after launch, the spacecraft was supposed to transmit signals to listening stations. This transmission was essential and its purpose was to make sure that the spacecraft was operating as normal, however, no signs were received that would indicate the spacecraft's activity even half an hour after the launch.
Pioneer 31 -P
On December 15, 1960, the spacecraft was launched with the aim of entering orbit around the moon using the Thor-Abel launcher. A few seconds after the launch at an altitude of 1,016 km, the launcher and the spacecraft exploded due to a malfunction in one of the parts of the first stage of the launcher - Atlas.
Ranger program
The second program in the United States' studies of the moon and towards a manned landing on its surface was the Ranger program. This series had two stages. First phase Ranger 1 to Ranger 5. The role of the spaceships of this phase was to collect information and test certain components of the space technology needed for lunar flights and various places in the solar system. The spacecraft were equipped with televisions with a resolution of 7.62 cm. The spacecraft began transmitting when they were 2,100 km away from it until the moment they crashed on its surface.
The second series of spacecraft was from Ranger 6 to Ranger 9. The total weight of such a spacecraft is 366 kg and its height is 3.1 meters. Each spaceship has two sun shelves, each 4.6 meters long. The launcher was an Atlas Agena D. A 170 kg cone-shaped spacecraft on which six television cameras are placed. Two cameras with a wide shooting angle and four cameras with a narrow shooting angle, a video device, a transmitter and more. The shooting time from the moment the shooting began until the impact on the lunar surface - 14 minutes. At an altitude of 2,261 km, the flight speed is 9,330 km/h. As soon as the spacecraft approached the moon, a small spacecraft moving on a collision course with the ground broke away from it. During disengagement, its speed is slowed by a small braking motor. The impact of the landing is softened by a crisp balsa container.
The equipment of one of the spaceships included a seismometer designed to report noises and impact of meteorites. Another spacecraft had a tiny television camera that transmitted detailed pictures of the surface of the moon from the impact site. The images made it possible to discover characteristic features of the moon's surface down to a size of 0.254 cm. The information accumulated during the Ranger program was intended to significantly advance man's knowledge of the moon and to plan a manned flight to it.
The first six spacecraft failed. The first two spacecraft failed to take off, two others did not hit the moon and two spacecraft failed to activate their scientific instruments due to malfunctions in the launchers or themselves. Despite this, it was in them to promote the technologies of these spacecraft in important areas such as repairing spacecraft during their flight and stabilization. The difficulties of photography are enormous and the main ones are:
In order for the Ranger cameras to photograph the surface of the moon and not somewhere else, they must be given a specific direction in relation to the moon, the sun and the earth and maintain this fixed direction for the entire duration of the photo. Only this secondary mission requires the following equipment - an electronic system for detecting deviation between the direction of a special directional antenna that maintains contact with the earth and the spacecraft's computer.
1. Six photoelectric cells for detecting the relative direction of the spacecraft in relation to the sun and the earth.
2. Three gyroscopes.
3 A computer that receives the information about the state of the spacecraft and translates it into appropriate commands for the navigation mechanism.
4. Steering mechanism, which includes a mechanism for correcting the flight path with a thrust force of 226 kg and a duration of operation of 98 seconds and 12 tiny exhaust nozzles filled with gas for reference control.
5. A delicate and precise mechanical mechanism for executing computer commands.
The launch date
The launch is only suitable for one week a month. Here the movement of the earth around its axis must be added. In order for the spaceship to reach the moon, it must enter the "narrow" corridor" fixed in space. The diameter of this corridor is 16 km. Permissible deviation in the entrance speed into the vestibule is about two km/h. Failure to hit the vestibule or a large deviation from the permitted speed means that the moon is wasted even if the full possibility of correcting the route halfway is used. Since the launcher has its own limitations in relation to maneuvering. Only 50-70 minutes a day are possible for a launch that will put the spacecraft into the entrance hall. The last instructions to the launcher's navigation mechanism must be given when the launch time is known with an accuracy of seconds. From Ranger's photographs it became clear that the surface of the moon is made of rocky material - rock and porous, probably due to the incessant bombardment for millions of years.
Ranger 1 Ranger 2
These two spacecraft were used to test the systems. They were launched in 1961 into a highly elliptical orbit around the Earth. Malfunctions in their navigation engines caused them to be moved into extremely low orbit and soon reentered the atmosphere and burned up. Despite this, the researchers were able to test some of their systems. Ranger 1 was launched on August 23, 1961, and Ranger 2 was launched on November 18, 1961.
Ranger 3
The spacecraft was launched on January 26, 1962 by the Atlas-Agina launcher. The weight of the instrument compartment was 25 kg and it contained a TV camera, measuring devices and a radio transmitter. The mission of the spacecraft was to investigate the formations of the rays coming out of different craters and to solve the question of the origin of the craters on the moon. At a height of 21 km from the surface of the moon, the instrument compartment was supposed to detach from the spacecraft when the spacecraft's flight speed is slowed to 9,600 km/h and land on the ground at a speed less than 240 km/h. Ranger 3 missed the moon by 36,793 km and entered an orbit around the sun that is 147 - 173.8 million km away and the duration of the orbit is 406.4 days.
Ranger 4
On April 23, 1962, the spacecraft was launched by the Atlas-Agina B launcher. The weight of the spacecraft is 328 kg. Just an hour before landing, the spacecraft was supposed to eject the 150 kg instrument compartment equipped with braking motors. After activating them, the instrument cabin had to land at a speed of 150 km/h. In this cell were a seismometer, measuring devices and a radio transmitter. These instruments were supposed to transmit to Earth data about earthquakes on the moon, meteorite impacts and temperatures. The photograph of the moon had to start from an altitude of 4,000 km and end at an altitude of 24 km from the ground. The spacecraft went into a spin, missed the moon by 145 km and crashed on its hidden side. The spacecraft's computer crashed during the flight and the spacecraft's instruments could not transmit any data.
Ranger 5
On October 18, 1962, the spacecraft was launched by the Atlas-Agina launcher. The spacecraft was supposed to pass by the moon while photographing its surface. On October 20, there was a malfunction in the spacecraft's operating mechanism. The malfunction did not allow the solar arrays to operate and prevented the correction of a navigation error, due to which the distance of the passage from the face of the moon was greater than planned. The spacecraft passed at a distance of 724 km from it and entered an orbit around the sun similar to that of Ranger 3.
Ranger 6
On January 30, 1964, the spacecraft was launched. The purpose of the launch was to check if the surface of the moon is hard and to transmit 3,000 images covering an area of 24,000 km by 1,200 km. Unfortunately the spacecraft's power systems burned up after liftoff. In the last 10 minutes of the flight, an attempt was made to activate the cameras and it failed. Nevertheless the flight was perfect. The spacecraft crashed near the Argo crater. The landing place was illuminated at the time of landing.
Ranger 7
On July 28, 1964, the spacecraft was launched. The purpose of the flight was to photograph the western side of the moon. Several changes were introduced in the spacecraft and especially in the pre-flight test processes. The TV box was returned to the RCA company to carry out repairs that would prevent the recurrence of Ranger 6's malfunctions. On July 31, Ranger 7 crashed into the "familiar sea" located between the Guarica and Lubintzky craters. The spacecraft transmitted 4,316 photographs in 16 minutes. and 40 seconds. In these photos, you can see details that range from 3 to 5 meters in diameter. It turned out that the surface of the moon at the impact site is dotted with many craters of various sizes and almost all of them are covered with a thin layer of dust, which showed that manned landings in these places are possible. The first photo was taken from an altitude of 2,100 km and the last from an altitude of 300 meters. This image covered an area measuring 18 x 39 meters. The photographs were so clear and detailed that it was decided to give this area the name "Mera Cognitium" - the familiar sea.
Ranger 8
On February 17, 1965, the spacecraft was launched. 65 hours later on February 20, it hit the moon, in the Sea of Tranquility, 59 0 2 above the equator and 7 0 22 east of the center of the full moon, 25 km from the original impact site 1,600 km east of Ranger 7. The spacecraft Approached the moon at a smaller angle than its predecessors (the impact angle was 0 42) its cameras are directed downwards and it scans the surface like a mapping plane. Ranger 8 transmitted 7,137 photographs over 23 minutes. The photographs were sharper than those of Ranger 7, because the latter hit a point that was closer to the moon's shadow line, a place where the mountains and craters are highlighted by the rays of the setting sun. The photographs covered an area of 2,331,000 square kilometers. In the latest photographs, objects measuring 1.5 meters can be seen.
Ranger 9
On March 21, 1965, the spacecraft was launched in order to find landing sites suitable for manned spacecraft. The spacecraft was aimed at the Alphonsis Crater. 64.5 hours after launch Ranger 9 hit the target exactly. An hour and a half before impact, the navigation engines were activated to rotate the spacecraft so that the cameras would be aimed directly at the moon. Ranger 7 transmitted 5,814 photographs. One can distinguish objects that are 30 cm in size. The photographs covered an area of 417,054 square kilometers.
