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73-625: The Titan IIIE or Titan 3E , also known as the Titan III-Centaur , was an American expendable launch system . Launched seven times between 1974 and 1977, it enabled several high-profile NASA missions, including the Voyager and Viking planetary probes and the joint West Germany-U.S. Helios spacecraft . All seven launches were conducted from Cape Canaveral Air Force Station Launch Complex 41 in Cape Canaveral, Florida . In

146-522: A core diameter of 1.25 m, with two liquid propellant stages, a single thrust chambered first stage and a two-thrust chambered, step-throttled second stage, the SLV has a lift off mass exceeding 26 tons. The first stage consists of a lengthened up-rated Shahab-3C . According to the technical documentation presented in the annual meeting of the United Nations Office for Outer Space Affairs , it is

219-483: A crude Sun sensor . Guidance corrections were performed using cold gas thrusters (7.7 kg nitrogen ) with a boost of 1   Newton . The axis of the probe was permanently maintained keeping it both perpendicular to the direction of the Sun and to the ecliptic plane. The onboard controllers were capable of handling 256 commands. The mass memory could store 500  kb , (this was a very large memory for space probes of

292-518: A launch vehicle more powerful than Atlas-Centaur to send heavier planetary probes like Viking and Voyager into space in the 1970s. So, NASA began in 1967 to consider the possibility of mating a Centaur upper stage with the Titan III . On June 26, NASA contracted with Martin Marietta to study its feasibility. By March 1969, this combination looked promising. NASA assigned management of the vehicle to

365-401: A maximum diameter of 2.77 metres (9 ft 1 in). Once in orbit, the telecommunications antennae unfolded on top of the probes and increased the heights to 4.2 metres (14 ft). Also deployed were two rigid booms carrying sensors and magnetometers, attached on both sides of the central bodies, and two flexible antennae used for the detection of radio waves, which extended perpendicular to

438-468: A maximum speed record for spacecraft of 252,792 km/h (157,078 mph; 70,220 m/s). Helios-B performed the closest flyby of the Sun of any spacecraft until that time. The probes are no longer functional, but as of 2024 remain in elliptical orbits around the Sun. The Helios project was a joint venture of West Germany 's space agency DLR (70 percent share) and NASA (30 percent share). As built by

511-464: A period from solar minimum in 1976 to a solar maximum in the early 1980s. The observation of the zodiacal light established some of the properties of interplanetary dust present between 0.1 and 1 AU from the Sun, such as their spatial distribution, color and polarization . The amount of dust was observed to be 10 times that around the Earth. Heterogeneous distribution was generally expected due to

584-425: A record distance of 43.432 million km (26,987,000 mi; 0.29032 AU), closer than the orbit of Mercury . Helios-B was sent into orbit 13 months after the launch of Helios-A . Helios-B performed the closest flyby of the Sun of any spacecraft until Parker Solar Probe in 2018, 0.29 AU (43.432 million km) from the Sun. The Helios space probes completed their primary missions by

657-422: A signal in all directions of the ecliptic plane at the height of 15°, and a low-gain dipole antenna (0.3 dB transmission and 0.8 dB for reception). To be directed continuously toward Earth , the high-gain antenna is rotated by a motor at a speed that counterbalances the spin of the probe. Synchronizing the rotation speed is performed using data supplied by a Sun sensor . The maximum data rate obtained with

730-462: A two-stage rocket with all liquid propellant engines. The first stage is capable of carrying the payload to the maximum altitude of 68 kilometres. The Israel Space Agency is one of only seven countries that both build their own satellites and launch their own launchers. The Shavit is a space launch vehicle capable of sending payload into low Earth orbit . The Shavit launcher has been used to send every Ofeq satellite to date. The development of

803-507: Is a French company founded in March 1980 as the world's first commercial launch service provider . It operates two launch vehicles : Vega C , a small-lift rocket , and Ariane 6 , a medium -to- heavy-lift rocket. Arianespace is a subsidiary of ArianeGroup , a joint venture between Airbus and Safran . European space launches are carried out as a collaborative effort between private companies and government agencies. The role of Arianespace

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876-663: Is a launch vehicle that improved reliability while reducing costs by making significant improvements to the H-II, and the M-V was the world's largest solid-fuel launch vehicle at the time. In November 2003, JAXA's first launch after its inauguration, H-IIA No. 6, failed, but all other H-IIA launches were successful, and as of February 2024, the H-IIA had successfully launched 47 of its 48 launches. JAXA plans to end H-IIA operations with H-IIA Flight No. 50 and retire it by March 2025. JAXA operated

949-469: Is a measure of the density of electrons and the intensity of the magnetic field in the traversed region. Helios-A was launched on December 10, 1974, from Cape Canaveral Air Force Station Launch Complex 41 in Cape Canaveral, Florida . This was the first operational flight of the Titan IIIE rocket. The rocket's test flight had failed when the engine on the upper Centaur stage did not light, but

1022-632: Is also an ELV customer, having designed the Titan, Atlas, and Delta families. The Atlas V from the 1994 Evolved ELV (EELV) program remains in active service, operated by the United Launch Alliance . The National Security Space Launch (NSSL) competition has selected two EELV successors, the expendable Vulcan Centaur and partially reusable Falcon 9 , to provide assured access to space. Iran has developed an expendable satellite launch vehicle named Safir SLV . Measuring 22 m in height with

1095-556: Is measured with an accuracy to within 0.4   nT when below 102.4   nT, and within 1.2   nT at intensities below 409.6   nT. Two sample rates are available: search every two seconds or eight readings per second. Measures variations of the field strength and direction of low frequency magnetic fields in the Sol environment. Developed by the Goddard Space Flight Center of NASA; measures variations of

1168-694: Is to market Ariane 6 launch services, prepare missions, and manage customer relations. At the Guiana Space Centre (CSG) in French Guiana , the company oversees the team responsible for integrating and preparing launch vehicles. The rockets themselves are designed and manufactured by other companies: ArianeGroup for the Ariane 6 and Avio for the Vega. The launch infrastructure at the CSG is owned by

1241-556: Is very experienced in development, assembling, testing and operating system for use in space. Helios (spacecraft) Helios-A and Helios-B (after launch renamed Helios 1 and Helios 2 ) are a pair of probes that were launched into heliocentric orbit to study solar processes. As a joint venture between German Aerospace Center (DLR) and NASA , the probes were launched from Cape Canaveral Air Force Station , Florida , on December   10, 1974, and January   15, 1976, respectively. The Helios project set

1314-631: The European Space Agency , while the land itself belongs to and is managed by CNES , the French national space agency. During the 1960s and 1970s, India initiated its own launch vehicle program in alignment with its geopolitical and economic considerations. In the 1960s–1970s, the country India started with a sounding rocket in the 1960s and 1970s and advanced its research to deliver the Satellite Launch Vehicle-3 and

1387-813: The H-IIB , an upgraded version of the H-IIA, from September 2009 to May 2020 and successfully launched the H-II Transfer Vehicle six times. This cargo spacecraft was responsible for resupplying the Kibo Japanese Experiment Module on the International Space Station . To be able to launch smaller mission on JAXA developed a new solid-fueled rocket, the Epsilon as a replacement to the retired M-V . The maiden flight successfully happened in 2013. So far,

1460-533: The Max Planck Institute for Astronomy to measure the intensity and polarization of the zodiac light in white light and in the 550   nm and 400 nm wavelength bands, using three telescopes whose optical axes form angles of 15, 30, and 90° to the ecliptic. From these observations, information is obtained about the spatial distribution of interplanetary dust and the size and nature of the dust particles. The Micrometeoroid analyzer developed by

1533-414: The Max Planck Institute for Nuclear Physics is capable of detecting cosmic dust particles if their mass is greater than 10   g. It can determine the mass and energy of a micro-meteorite greater than 10   g. These measurements are made by exploiting the fact that micrometeorites vaporize and ionize when they hit a target. The instrument separates the ions and electrons in the plasma generated by

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1606-717: The NASA Lewis Research Center (now known as the NASA John H. Glenn Research Center at Lewis Field) with follow-on contracts with Martin Marietta to develop what became the Titan IIIE and General Dynamics to adapt the Centaur D-1. Several modifications to the Centaur were necessary to accommodate the more powerful booster. The most obvious change was enclosing Centaur in a large shroud to protect

1679-665: The Redstone missile to the Delta , Atlas , Titan and Saturn rocket families, have been expendable. As its flagship crewed exploration replacement for the partially reusable Space Shuttle , NASA's newest ELV, the Space Launch System flew successfully in November 2022 after delays of more than six years. It is planned to serve in a major role on crewed exploration programs going forward. The United States Air Force

1752-479: The University of Kiel sought to determine the intensity, direction, and energy of the protons and heavy constituent particles in radiation to determine the distribution of cosmic rays. The three detectors ( semiconductor detector , scintillation counter , and Cherenkov detector ) were encapsulated in an anti-coincidence detector. The Cosmic Ray Instrument developed at the Goddard Space Flight Center measures

1825-439: The magnetic field in the 5   Hz to 3000   Hz range. The spectral resolution is performed on the probe's rotation axis. The Plasma Wave Investigation developed by the University of Iowa uses two 15 m antennas forming an electric dipole for the study of electrostatic and electromagnetic waves in the solar wind plasma in frequencies between 10 Hz and 3 MHz. The Cosmic Radiation Investigation developed by

1898-453: The Centaur had been damaged by colliding with the second stage were disproven by accelerometer data and instead it was suspected that loose debris or ice had caused the boost pump to seize up. To reduce the chance of a second failure, prelaunch procedures were implemented to verify that Centaur's pumps were free and unobstructed. Nearly four years passed before the cause of the failure was determined: an improperly installed mounting bracket inside

1971-628: The Centaur in free-fall, the Range Safety station in Antigua sent the destruct command at T+748 seconds. Examination of telemetry data revealed that the Centaur's LOX boost pump did not activate, preventing proper mainstage engine operation from being achieved. The guidance system issued a shutdown command after the first engine start attempt due to insufficient acceleration. After the second attempt, it entered coasting mode as it would have had orbital injection been achieved. Initial suspicions that

2044-494: The Centaur was only 3.4 seconds from propellant exhaustion. If the same failure had occurred during Voyager 2 ' s launch a few weeks earlier, the Centaur would have run out of propellant before the probe reached the correct trajectory. Jupiter was in a more favorable position vis-à-vis Earth during the launch of Voyager 1 than during the launch of Voyager 2 . [REDACTED] Media related to Titan IIIE at Wikimedia Commons Expendable launch system Arianespace SA

2117-499: The Deep Space Network antennas that Helios-B needed to conduct its science while at perihelion unavailable. Helios-B was launched on January 10, 1976, using a Titan IIIE rocket. The probe was placed in an orbit with a 187-day period and a perihelion of 43,500,000 km (27,000,000 mi; 0.291 AU). The orientation of Helios-B with respect to the ecliptic was reversed 180 degrees compared to Helios-A so that

2190-584: The Shavit began in 1983 and its operational capabilities were proven on three successful launches of the Ofek satellites on September 19, 1988; April 3, 1990; and April 5, 1995. The Shavit launchers allows low-cost and high-reliability launch of micro/mini satellites to a low Earth orbit . The Shavit launcher is developed by Malam factory, one of four factories in the IAI Electronics Group. The factory

2263-420: The Sun, approximate heat flow is 11 solar constants , (11 times the amount of solar irradiance received while in Earth orbit), or 22.4  kW per exposed square meter. At that distance, the probe could reach 370 °C (698 °F). The solar cells , and the central compartment of instruments had to be maintained at much lower temperatures. The solar cells could not exceed 165 °C (329 °F), while

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2336-410: The Sun, was measured. These observations, combined with those made by Pioneer   11 between 1977 and 1980 in a distance of 12–23   AU from the Sun produced a good model of this gradient . Some features of the inner solar corona were measured during occultations. For this purpose, either a radio signal was sent from the spacecraft to Earth or the ground station sent a signal that was returned by

2409-676: The Titan IIIE on February 11, 1974, was a failure. As a "Proof Flight", it was planned to have the same trajectory as the Viking mission to Mars that was scheduled for launch in 1975. The original plan was for this flight to carry the Viking Dynamic Simulator (VDS), a model of the Viking spacecraft. Engineers at the Lewis Research Center, however, ultimately persuaded their colleagues to put the Sphinx satellite on

2482-456: The Titan IIIE was on December 10, 1974, carrying the Helios-A spacecraft. This mission was successful, as were all subsequent launches. Voyager 1 ' s launch almost failed because Titan's second stage shut down too early, leaving 1,200 pounds (540 kg) of propellant unburned. To compensate, the Centaur's on-board computers ordered a burn that was far longer than planned. At cutoff,

2555-463: The analyzer particles and the radio receiver. To reduce the interference, communications were carried out using reduced power, but this required using the large diameter terrestrial receivers already in place thanks to other space missions in progress. During the first perihelion in late February 1975, the spacecraft came closer to the Sun than any previous spacecraft. The temperature of some components reached more than 100 °C (212 °F), while

2628-437: The axes of the spacecraft for a design length of 16 metres (52 ft) each. The spacecraft spin around their axes, which are perpendicular to the ecliptic , at 60   rpm . Electrical power is provided by solar cells attached to the two truncated cones. To keep the solar panels at a temperature below 165 °C (329 °F) when in proximity to the Sun, the solar cells are interspersed with mirrors, covering 50% of

2701-431: The boil-off of Centaur's cryogenic fuels . The Centaur stage also contained the guidance system for the entire launch vehicle. A four-stage configuration was available, with a Star-37E being the additional upper stage. This was used for the two Helios launches. Star-37E stages were also used on the two Voyager launches, but the stages were considered part of the payload instead of part of the rocket. The first launch of

2774-539: The bolt with the wrench specified in the assembly instructions, the wrench was too short and prevented him from screwing it into place properly. The bolt came loose, fell off, and got sucked into one of the LOX boost pumps, which jammed the pump and prevented its operation. Despite the failure, at least one important goal was achieved. The Centaur's bulging shroud was proven to be aerodynamically stable during flight and had jettisoned properly and on schedule. One other minor problem

2847-475: The central compartment had to be maintained between −10 and 20 °C (14 and 68 °F). These restrictions required the rejection of 96 percent of the energy received from the Sun. The conical shape of the solar panels was decided on to reduce heating. Tilting the solar panels with respect to sunlight arriving perpendicularly to the axis of the probe, reflects a greater proportion of the solar radiation . "Second surface mirrors" specially developed by NASA cover

2920-659: The characteristics of protons with energies between 0.1 and 800   MeV and electrons with energies between 0.05 and 5   MeV. It uses three telescopes, which cover the ecliptic plane. A proportional counter studies the X-rays from the Sun. Developed by the Max Planck Institute for Aeronomy , the low energy electron and proton spectrometer uses spectrometers to measure particle characteristics (protons) with energies between 20 keV and 2 MeV and electrons and positrons with an energy between 80 keV and 1 MeV. The Zodiacal light instrument includes three photometers developed by

2993-537: The density, speed, and temperature of the solar wind. Measurements were taken every minute, with the exception of flux density, which occurred every 0.1 seconds to highlight irregularities in plasma waves. Instruments used included: The flux-gate magnetometer measures the field strength and direction of low frequency magnetic fields in the Sun's environment. It was developed by the University of Braunschweig , Germany. It measures three-vector components of solar wind and its magnetic field with high precision. The intensity

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3066-419: The direction of the magnetic field at staggered distances from the Sun. The radio and plasma wave detectors were used to detect radio explosions and shock waves associated with solar flares, usually during solar maximum. The cosmic ray detectors studied how the Sun and interplanetary medium influenced the spread of the same rays, of solar or galactic origin. The cosmic ray gradient, as a function of distance from

3139-400: The early 1960s, NASA's long-range plan was to continue using Atlas-Centaur until a reusable launch system or a nuclear-powered upper stage could be developed. To help fund the escalating Vietnam War and the new War on Poverty , Congress drastically reduced the funding of the civilian space program. In addition, further development of the reusable launch vehicle was postponed. NASA needed

3212-401: The early 1980s, but continued to send data until 1985. Both Helios probes had ten scientific instruments and two passive science investigations using the spacecraft telecommuniction system and the spacecraft orbit. Measures the velocity and distribution of solar wind plasma. Developed by the Max Planck Institute for Aeronomy for the study of low-energy particles. Data collected included

3285-429: The entire central body and 50 percent of the solar generators. These are made of fused quartz, with a silver film on the inner face, which is itself covered with a dielectric material. For additional protection, multi-layer insulation  – consisting of 18 layers of 0.25 millimetres (0.0098 in) Mylar or Kapton (depending on location), held apart from each other by small plastic pins intended to prevent

3358-430: The equipment and instrumentation is mounted in this central body. The exceptions are the masts and antennae used during experiments and small telescopes that measure the zodiacal light and emerge from the central body. Two conical solar panels extend above and below the central body, giving the assembly the appearance of a diabolo or spool of thread. At launch, each probe was 2.12 metres (6 ft 11 in) tall with

3431-479: The flight in addition to the VDS. The mission of the satellite was to measure the interaction of space plasmas with the satellite's high-voltage surfaces. The Titan phase of the flight was largely uneventful and second stage cutoff and Centaur separation were effected at T+469 seconds. However, the Centaur failed to start. A backup command from the missile programmer at T+525 seconds failed to initiate main engine start. With

3504-415: The formation of thermal bridges  – was used to partially cover the core compartment. In addition to these passive devices, the probes used an active system of movable louvers arranged in a shutter-like pattern along the bottom and top side of the compartment. The opening thereof is controlled separately by a bimetal spring whose length varies with temperature and causes the opening or closing of

3577-504: The high-speed solar wind were associated with the presence of coronal holes. This instrument also detected, for the first time, helium ions isolated in the solar wind. In 1981, during the peak of solar activity, the data collected by Helios-A at a short distance from the Sun helped to complete visual observations of coronal mass ejections performed from the Earth's orbit. Data collected by Helios magnetometers supplemented data collected by Pioneer and Voyager and were used to determine

3650-503: The impacts, and measures the mass and energy of the incident particle. A low-resolution mass spectrometer determines the composition of impacting cosmic dust particles with a mass greater than 10   g. The Celestial Mechanic Experiment developed by the University of Hamburg uses the Helios orbit specifics to clarify astronomical measurements: flattening of the Sun; verification of predicted general relativity effects; determining

3723-403: The implementation mechanism of the flexible antenna and high gain antenna emissions. The X-ray detectors were improved so that they could detect gamma ray bursts , allowing them to be used in conjunction with Earth-orbiting satellites to triangulate the location of the bursts. As temperatures on Helios-A were always greater than 20 °C (36 °F) below the design maximum at perihelion, it

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3796-475: The large antenna gain was 4096 bits per second upstream. The reception and transmission of signals were supported by the Deep Space Network antennas on Earth. To maintain orientation during the mission, the spacecraft rotated continuously at 60 RPM around its main axis. The orientation control system manages the speed and orientation of the probe's shafts. To determine its orientation, Helios used

3869-461: The launch of Helios-A was uneventful. The probe was placed in a heliocentric orbit of 192 days with a perihelion of 46,500,000 km (28,900,000 mi; 0.311 AU) from the Sun. Several problems affected operations. One of the two antennas did not deploy correctly, reducing the sensitivity of the radio plasma apparatus to low-frequency waves. When the high-gain antenna was connected, the mission team realized that their emissions interfered with

3942-408: The liquid oxygen (LOX) tank. This bracket held a LOX regulator in place. The technician responsible for installing it had found that the normal tool used to screw bolts into place was too short to reach the bracket. He thus used a slightly longer socket wrench that gave him more reach. Before the technician retired, he failed to inform his successor about this. When the new technician attempted to attach

4015-713: The main contractor, Messerschmitt-Bölkow-Blohm , they were the first space probes built outside the United States and the Soviet Union to leave Earth orbit. The two Helios probes look similar. Helios-A has a mass of 370 kilograms (820 lb), and Helios-B has a mass of 376.5 kilograms (830 lb). Their scientific payloads have a mass of 73.2 kilograms (161 lb) on Helios-A and 76.5 kilograms (169 lb) on Helios-B . The central bodies are sixteen-sided prisms 1.75 metres (5 ft 9 in) in diameter and 0.55 metres (1 ft 10 in) high. Most of

4088-520: The mass of the planet Mercury ; the Earth–Moon mass ratio; and the integrated electron density between the Helios spacecraft and the data receiving station on Earth. The Coronal Sounding Experiment developed by the University of Bonn measures the rotation ( Faraday effect ) of the linear polarized radio beam from the spacecraft when it passes during opposition through the corona of the Sun. This rotation

4161-458: The micrometeorite detectors could have 360 degree coverage. On April 17, 1976, Helios-B made its closest pass of the Sun at a record heliocentric speed of 70 kilometres per second (250,000 km/h; 160,000 mph). The maximum recorded temperature was 20 °C (36 °F) higher than measured by Helios-A . The primary mission of each probe spanned 18 months, but they operated much longer. On March   3, 1980, four years after its launch,

4234-546: The more advanced Augmented Satellite Launch Vehicle (ASLV), complete with operational supporting infrastructure by the 1990s. Japan launched its first satellite, Ohsumi , in 1970, using ISAS' L-4S rocket. Prior to the merger, ISAS used small Mu rocket family of solid-fueled launch vehicles, while NASDA developed larger liquid-fueled launchers. In the beginning, NASDA used licensed American models. The first model of liquid-fueled launch vehicle developed domestically in Japan

4307-746: The most famous of them being the R-7 , commonly known as the Soyuz rocket that is capable of launching about 7.5 tons into low Earth orbit (LEO). The Proton rocket (or UR-500K) has a lift capacity of over 20 tons to LEO. Smaller rockets include Rokot and other Stations. Several governmental agencies of the United States purchase ELV launches. NASA is a major customer with the Commercial Resupply Services and Commercial Crew Development programs, also launching scientific spacecraft. The vast majority of launch vehicles for its missions, from

4380-471: The passage of comets, but observations have not confirmed this. Helios collected data about comets, observing the passage of C/1975 V1 (West) in 1976, C/1978 H1 (Meir) in November 1978 and C/1979 Y1 (Bradfield) in February 1980. During the last event, probe detected disturbances in solar wind later explained by a break in the comet's tail. The plasma analyzer showed that the acceleration phenomena of

4453-413: The radio transceiver on Helios-B failed. On January   7, 1981, a stop command was sent to prevent possible radio interference during future missions. Helios-A continued to function normally, but with the large-diameter DSN antennae not available, data was collected by small diameter antennae at a lower rate. By its 14th orbit, Helios-A' s degraded solar cells could no longer provide enough power for

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4526-468: The rocket has flown six times with one launch failure. In January 2017, JAXA attempted and failed to put a miniature satellite into orbit atop one of its SS520 series rockets. A second attempt on 2 February 2018 was successful, putting a four kilogram CubeSat into Earth orbit. The rocket, known as the SS-520-5, is the world's smallest orbital launcher. Roscosmos uses a family of several launch rockets,

4599-414: The shutter. Resistors were also used to help maintain a temperature sufficient for certain equipment. The telecommunication system uses a radio transceiver, whose power could be adjusted to between 0.5 and 20 watts. Three antennas are mounted on top of each probe. A high-gain antenna (23  dB ) of 11° beam width, a medium-gain antenna (3 dB for transmission and 6.3 dB for reception) emits

4672-471: The simultaneous collection and transmission of data unless the probe was close to its perihelion. In 1984, the main and backup radio receivers failed, indicating that the high-gain antenna was no longer pointed towards Earth. The last telemetry data was received on February   10, 1986. Both probes collected important data about solar wind processes and the particles that make up the interplanetary medium and cosmic rays . These observations were made over

4745-458: The solar panels reached 127 °C (261 °F), without affecting probe operations. During the second pass on September 21, however, temperatures reached 132 °C (270 °F), which affected the operation of certain instruments. Before Helios-B was launched, some modifications were made to the spacecraft based on lessons learned from the operations of Helios-A . The small engines used for attitude control were improved. Changes were made to

4818-437: The stage and payload during ascent. The shroud made it possible to improve Centaur's insulation and thereby increase its coast time in orbit from thirty minutes when launched on an Atlas-Centaur to over five hours on the Titan IIIE. Because Centaur was wider than the Titan's core stage, a tapering interface was required. This interface needed insulation to prevent Titan's ambient-temperature hypergolic propellants from causing

4891-466: The surface and reflecting part of the incident sunlight while dissipating the excess heat. The power supplied by the solar panels is a minimum of 240   watts when the probe is at aphelion . Its voltage is regulated to 28   volts DC . Silver-zinc batteries were used only during launch. The biggest technical challenge was to avoid heating during orbit while close to the Sun. At 0.3 astronomical units (45,000,000 km; 28,000,000 mi) from

4964-501: The three-vector components of solar wind and its magnetic field with an accuracy to within 0.1   nT at about 25   nT, within 0.3   nT at about 75   nT, and within 0.9   nT at an intensity of 225   nT . The search coil magnetometer complements the flux-gate magnetometer by measuring the magnetic fields between 0 and 3 kHz. Also developed by the University of Braunschweig, it detects fluctuations in

5037-495: The time), and was mainly used when the probes were in superior conjunction relative to the Earth (i.e. the Sun comes between the Earth and the spacecraft). A conjunction could last up to 65 days. Helios-A and Helios-B were launched on December 10, 1974, and January 15, 1976, respectively. Helios-B flew 3,000,000 kilometres (1,900,000 mi) closer to the Sun than Helios-A , achieving perihelion on April   17, 1976, at

5110-537: Was carried over to its successor, the H-IIA and H-IIB and became the basic configuration of Japan's liquid fuel launch vehicles for 30 years, from 1994 to 2024. In 2003, JAXA was formed by merging Japan's three space agencies to streamline Japan's space program, and JAXA took over operations of the H-IIA liquid-fueled launch vehicle, the M-V solid-fuel launch vehicle, and several observation rockets from each agency. The H-IIA

5183-623: Was decided that Helios-B would orbit even closer to the Sun, and the thermal insulation was enhanced to allow the satellite to resist 15 percent higher temperatures. Tight schedule constraints pressed on the Helios-B launch in early 1976. Facilities damaged during the launch of the Viking 2 spacecraft in September 1975 had to be repaired, while the Viking landing on Mars in summer 1976 made

5256-445: Was evident: At T+179 seconds, Titan thrust assembly #2 experienced a 2% thrust decay. This was accompanied by a small drop in turbopump speed and gas generator performance. Consequently, the Titan core stage cut off two seconds later than nominal. The anomaly was traced to a cover on an unused instrumentation port on the turbine inlet coming loose during launch, allowing hot gas from the gas generator to leak out of it. The next flight of

5329-619: Was the H-II , introduced in 1994. NASDA developed the H-II with two goals in mind: to be able to launch satellites using only its own technology, such as the ISAS, and to dramatically improve its launch capability over previous licensed models. To achieve these two goals, a staged combustion cycle was adopted for the first stage engine, the LE-7 . The combination of the liquid hydrogen two-stage combustion cycle first stage engine and solid rocket boosters

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