Pioneer P-30
Encyclopedia
Pioneer P-30 was intended to be a lunar orbiter probe, but the mission failed shortly after launch on September 25, 1960. The objectives were to place a highly instrumented probe in lunar orbit, to investigate the environment between the Earth
and Moon
, and to develop technology for controlling and maneuvering spacecraft from Earth. It was equipped to estimate the Moon's mass and topography of the poles, record the distribution and velocity of micrometeorites, and study radiation
, magnetic field
s, and low frequency electromagnetic waves in space. A mid-course propulsion system and injection rocket would have been the first United States
self-contained propulsion system capable of operation many months after launch at great distances from Earth and the first U.S. tests of maneuvering a satellite in space.
. Signals were returned by the payload for 1020 seconds after launch. The mission was designed to reach the Moon approximately 62 hours after launch. Although the mission was a failure, ground controllers fired Able VA’s onboard liquid propellant hydrazine rocket engine — the first time that an onboard motor was fired on a space vehicle.
satellite which failed, a 1 meter diameter sphere with a propulsion system mounted on the bottom giving a total length of 1.4 meters (55 inches). The mass of the structure and aluminum alloy shell was about 30 kg (65 lb) and the propulsion units roughly 90 kg (200 lb). Four solar panels, each 60×60 cm (24×24 inches) and containing 2200 solar cell
s in 22 100-cell nodules, extended from the sides of the spherical shell in a "paddle-wheel" configuration with a total span of about 2.7 meters (105 in). The solar panels charged nickel-cadmium batteries
. Inside the shell, a large spherical hydrazine tank made up most of the volume, topped by two smaller spherical nitrogen tanks and a 90 N injection rocket to slow the spacecraft down to go into lunar orbit, which was designed to be capable of firing twice during the mission. Attached to the bottom of the sphere was a 90 N vernier rocket for mid-course propulsion and lunar orbit maneuvers which could be fired four times.
Around the upper hemisphere of the hydrazine tank was a ring-shaped instrument platform which held the batteries in two packs, two 1.5 W UHF transmitters and diplexers, logic modules for scientific instruments, two command receivers, decoders, a buffer/amplifier, three converters, a telebit, a command box, and most of the scientific instruments. Two dipole UHF antennas protruded from the top of the sphere on either side of the injection rocket nozzle. Two dipole UHF antennas and a long VLF antenna protruded from the bottom of the sphere. The transmitters operated on a frequency of 378 megahertz.
Thermal control was planned to be achieved by fifty small "propeller blade" devices on the surface of the sphere. The blades themselves were made of reflective material and consist of four vanes which were flush against the surface, covering a black heat-absorbing pattern painted on the sphere. A thermally sensitive coil was attached to the blades in such a way that low temperatures within the satellite would cause the coil to contract and rotate the blades and expose the heat absorbing surface, and high temperatures would cause the blades to cover the black patterns. Square heat-sink units were also mounted on the surface of the sphere to help dissipate heat from the interior.
to measure total radiation flux, a proportional radiation counter telescope to measure high energy radiation, a scintillation counter
to monitor low-energy radiation, a VLF receiver for natural radio waves, a transponder to study electron density, and part of the flux-gate and search coil magnetometers mounted on the instrument platform. The micrometeorite detector and sun scanner were mounted on the sphere. The difference between the payload of Pioneer P-30 and the earlier Pioneer P-3 was the replacement of the TV facsimile system on P-3 with a scintillation spectrometer to study the Earth's (and possible lunar) radiation belts, mounted on the instrument platform, and a plasma probe mounted on the sphere to measure energy and momentum distribution of protons above a few kilovolts to study the radiation effect of solar flares. The total mass of the science package including electronics and power supply was roughly 60 kg (130 lb). Total cost of the mission was estimated at 9-10 million dollars.
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
and Moon
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
, and to develop technology for controlling and maneuvering spacecraft from Earth. It was equipped to estimate the Moon's mass and topography of the poles, record the distribution and velocity of micrometeorites, and study radiation
Radiation
In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...
, magnetic field
Magnetic field
A magnetic field is a mathematical description of the magnetic influence of electric currents and magnetic materials. The magnetic field at any given point is specified by both a direction and a magnitude ; as such it is a vector field.Technically, a magnetic field is a pseudo vector;...
s, and low frequency electromagnetic waves in space. A mid-course propulsion system and injection rocket would have been the first United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
self-contained propulsion system capable of operation many months after launch at great distances from Earth and the first U.S. tests of maneuvering a satellite in space.
Mission
The spacecraft was launched on an Air Force-Convair Atlas D intercontinental ballistic missile coupled to Thor-Able upper stages including a Hercules ABL solid propellant third stage. The first stage burned normally for 275 seconds, the two Atlas booster engines were jettisonned as planned after ~250 seconds. At an altitude of about 370 km (230 mi) the first stage separated from the second stage. When the second stage was ignited telemetry showed abnormal burning and the stage failed due to a malfunction in the oxidizer system. The vehicle was unable to achieve Earth orbit, re-entered and was believed to have come down somewhere in the Indian OceanIndian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
. Signals were returned by the payload for 1020 seconds after launch. The mission was designed to reach the Moon approximately 62 hours after launch. Although the mission was a failure, ground controllers fired Able VA’s onboard liquid propellant hydrazine rocket engine — the first time that an onboard motor was fired on a space vehicle.
Spacecraft design
Pioneer P-30 was almost identical to the earlier Pioneer P-3Pioneer P-3
Pioneer P-3 was intended to be a lunar orbiter probe, but the mission failed shortly after launch. The objectives were to place a highly instrumented probe in lunar orbit, to investigate the environment between the Earth and Moon, and to develop technology for controlling and maneuvering...
satellite which failed, a 1 meter diameter sphere with a propulsion system mounted on the bottom giving a total length of 1.4 meters (55 inches). The mass of the structure and aluminum alloy shell was about 30 kg (65 lb) and the propulsion units roughly 90 kg (200 lb). Four solar panels, each 60×60 cm (24×24 inches) and containing 2200 solar cell
Solar cell
A solar cell is a solid state electrical device that converts the energy of light directly into electricity by the photovoltaic effect....
s in 22 100-cell nodules, extended from the sides of the spherical shell in a "paddle-wheel" configuration with a total span of about 2.7 meters (105 in). The solar panels charged nickel-cadmium batteries
Nickel-cadmium battery
The nickel–cadmium battery ' is a type of rechargeable battery using nickel oxide hydroxide and metallic cadmium as electrodes....
. Inside the shell, a large spherical hydrazine tank made up most of the volume, topped by two smaller spherical nitrogen tanks and a 90 N injection rocket to slow the spacecraft down to go into lunar orbit, which was designed to be capable of firing twice during the mission. Attached to the bottom of the sphere was a 90 N vernier rocket for mid-course propulsion and lunar orbit maneuvers which could be fired four times.
Around the upper hemisphere of the hydrazine tank was a ring-shaped instrument platform which held the batteries in two packs, two 1.5 W UHF transmitters and diplexers, logic modules for scientific instruments, two command receivers, decoders, a buffer/amplifier, three converters, a telebit, a command box, and most of the scientific instruments. Two dipole UHF antennas protruded from the top of the sphere on either side of the injection rocket nozzle. Two dipole UHF antennas and a long VLF antenna protruded from the bottom of the sphere. The transmitters operated on a frequency of 378 megahertz.
Thermal control was planned to be achieved by fifty small "propeller blade" devices on the surface of the sphere. The blades themselves were made of reflective material and consist of four vanes which were flush against the surface, covering a black heat-absorbing pattern painted on the sphere. A thermally sensitive coil was attached to the blades in such a way that low temperatures within the satellite would cause the coil to contract and rotate the blades and expose the heat absorbing surface, and high temperatures would cause the blades to cover the black patterns. Square heat-sink units were also mounted on the surface of the sphere to help dissipate heat from the interior.
On-board equipment
The scientific instruments consisted of an ion chamber and Geiger-Müller tubeGeiger-Müller tube
A Geiger–Müller tube is the sensing element of a Geiger counter instrument that can detect a single particle of ionizing radiation, and typically produce an audible click for each. It was named for Hans Geiger who invented the device in 1908, and Walther Müller who collaborated with Geiger in...
to measure total radiation flux, a proportional radiation counter telescope to measure high energy radiation, a scintillation counter
Scintillation counter
A scintillation counter measures ionizing radiation. The sensor, called a scintillator, consists of a transparent crystal, usually phosphor, plastic , or organic liquid that fluoresces when struck by ionizing radiation. A sensitive photomultiplier tube measures the light from the crystal...
to monitor low-energy radiation, a VLF receiver for natural radio waves, a transponder to study electron density, and part of the flux-gate and search coil magnetometers mounted on the instrument platform. The micrometeorite detector and sun scanner were mounted on the sphere. The difference between the payload of Pioneer P-30 and the earlier Pioneer P-3 was the replacement of the TV facsimile system on P-3 with a scintillation spectrometer to study the Earth's (and possible lunar) radiation belts, mounted on the instrument platform, and a plasma probe mounted on the sphere to measure energy and momentum distribution of protons above a few kilovolts to study the radiation effect of solar flares. The total mass of the science package including electronics and power supply was roughly 60 kg (130 lb). Total cost of the mission was estimated at 9-10 million dollars.