784:, magnetosheath, and magnetotail. Energy spectral analysis was accomplished by charging the plates to known voltage levels and allowing them to discharge with known RC time constants. The analyzer had four commandable modes. The first mode was designed for the measurement of solar wind protons and alpha particles. During eight spacecraft revolutions, 32-level energy spectra were obtained in eight angular ranges centered on the sun. The energy levels extended from 100 eV to 8 keV. The second mode was designed for the measurement of solar wind heavy ions. This cycle was the same as the first except that the energy per charge levels were limited to 900 eV to 8 keV, and the efficiency of counting heavy ions was increased relative to protons and alpha particles. The third mode was designed for the measurement of solar wind and magnetosheath electrons and magnetosheath positive ions. This was a combination cycle in which electron and positive ion spectral sweeps were alternated. During a cycle of nine spacecraft revolutions, eight electron spectra and eight positive ion spectra were obtained. The combined data for electrons in this mode consisted of 16-level energy spectra taken in 32 evenly spaced angular ranges. The spectra extended from 4 to 1000 eV. The data for positive ions consisted of 32-level spectra taken in the same 32 angular ranges. The energy per charge spectra extended from 100 eV to 8 keV. The fourth mode was designed for magnetotail electrons and positive ions. Electrons and positive ions were studied with 16-level spectra in 32 evenly-spaced angular ranges for both electrons and positive ions. The energy per charge ranges were 6 eV to 24 keV for electrons and 45 eV to 34 keV for positive ions.
809:. The 20-keV electron data were accumulated and read out every 10.24-seconds. The other GM tube directly observed electrons and protons with energies greater than 18- and 250-keV, respectively. This type of data was accumulated and read out every 5.12-seconds. The third detector, a telescope consisting of three semiconductors, had a viewing direction of 170° with respect to the spacecraft spin axis. This detector responded to electrons and protons in the energy intervals 18- to 450-keV and 0.04- to 2-MeV, respectively. Electron data from this detector were accumulated in four contiguous logarithmically equispaced energy channels for 5.12-seconds and read out at the end of each time interval. In addition, a 64-channel, pulse-height analysis was performed on the detector counts, and this information was telemetered every 163.84-seconds. Proton data from this detector was accumulated and read out every 20.48-seconds. The fourth detector consisted of two semiconductors with a viewing direction perpendicular to the spacecraft spin axis. This detector responded to electrons with energies between 47- and 350-keV that were backscattered off a gold foil. Counts of 47- to 350-keV electrons and 80- to 350-keV electrons were accumulated in each of 16 and 4 equiangular sectors, respectively, during successive 20.48-seconds intervals, and they were read out at the end of each interval. The experiment functioned normally.
748:
cylindrical electrostatic analyzers and continuous channel multipliers were used for this purpose. One analyzer, the LEPEDEA (low-energy proton and electron differential energy analyzer), was to measure the energy spectra and angular distribution of protons and electrons separately in the energy range 24 eV to 50 keV (16 energy intervals for protons and electrons separately). The other analyzer, the LEPEDEA (low energy proton differential energy analyzer) measured the energy spectra and angular distribution of protons in the energy range 1.7 to 550 eV (eight energy intervals). The analyzers were mounted perpendicular to the spacecraft spin axis. An EON type 213 Geiger–Müller counter, whose collimated field of view of 15° half angle was oriented approximately parallel to that of the LEPEDEA, was used to measure the intensity of electrons of energies greater than 45 keV and protons of energies greater than 500 keV and to provide background measurements for the LEPDEA. One continuous channel electron multiplier failed on 10 August 1974, so that no useful electron data were collected for the last 7 weeks of the spacecraft life. Otherwise, the experiment functioned normally over the spacecraft lifetime.
868:. Counts of particles in the 0.5-to 4-MeV/nucleon range, with no charge resolution, were obtained as counts in the dE/dx, but not in the E, sensor. The third detector system was a three-element telescope whose axis made an angle of 39 deg with respect to the spin axis. The instrument responded to electrons between 2- and 12-MeV and Z=1 to 30 nuclei in the energy range 20- to 500-MeV/nucleon. For particles below 80-MeV, this instrument acted as a dE/dx vs E detector. Above 80-MeV, it acted as a bidirectional triple dE/dx vs E detector. By use of a combination of pulse-height analysis and gain switching, the output of each sensor of the second and third detector systems was sorted into one of 1000 and 1200 energy channels, respectively. Flux directionality information was obtained by dividing certain portions of the data from each detector into eight angular sectors. The second detector system performed normally from launch until 14 October 1971 (apogee shadow), after which problems were encountered. Essentially no data were obtained from this telescope after November 1971. Otherwise, the experiment functioned normally through the spacecraft life.
506:
843:(Tl) scintillator) and an anticoincidence scintillator. This telescope had a look direction that was normal to the spacecraft spin axis and had an angular aperture between 48° and 64° (depending on coincidence mode considered). Coincidence mode rates (5.12-seconds accumulations, corresponding to protons in the ranges 0.5 to 10.6, 10.6 to 19.6, 29.3 to 66.7 and above 66.7-MeV) were obtained each 10.24-seconds. Pulse-height analysis (one event every 20.48-seconds) was used with these rates to study charge composition (up to Z of 8), isotopic composition (for Z of 1 and 2), and electron fluxes. The spacecraft onboard computer was used to permit some of the objectives assigned to the composition telescope to be achieved through the smaller successful telescope. Except for the failure of the composition telescope, the experiment worked as planned throughout the spacecraft life.
2455:
894:, respectively. A fully shielded CsI crystal served as a gamma-ray spectrometer and was used in coincidence with the principal detector to distinguish electrons from positrons. Count rates from each detector obtained in eight angular sectors per revolution were telemetered. In addition, the amplitude and shape of the pulse generated in the principal detector by the first stopping particle in each appropriate telemetry frame were studied. Pulse amplitude and shape yielded energy (10% resolution) and particle species information. Initial experiment performance was normal. An experiment malfunction prevented the acquisition of useful data between the 7th and 12th weeks after launch. Marginal operation of part of the apparatus made it difficult to determine
877:
hourly averaged fluxes were published on a rapid basis in "Solar-Geophysical Data". The fourth detector, a two-element telescope, measured directional fluxes of protons in the energy intervals from 0.2 to 0.5, 0.5 to 2.0, and 2.0 to 7.5-MeV and directional fluxes of alpha particles in the energy interval from 8 to 20-MeV. The fifth detector measured directional fluxes of electrons above 10-keV. For the last two detectors, counts were obtained in 45° sectors as the spacecraft spun. Onboard calibration capability for the first four detectors was included.
864:
telescopes. Two were perpendicular and two were parallel to the spacecraft spin axis. Because the telescopes differed in their absorbing thicknesses, some discrimination between electrons and protons was possible. Each detector responded to particles between about 50-keV and 2-MeV. A seven-level integral analyzer was included for spectral information. The second detector system was a solid-state dE/dx vs E telescope that looked perpendicular to the spin axis. This telescope measured Z=1 to 16 nuclei with energies between 4- and 20-MeV/
95:
793:
only alpha particles with deflection voltages between 640 and 7200 volts. During successive spacecraft revolutions, each of the two electrostatic analyzer deflection voltages was advanced through one of 20 logarithmically equispaced steps in the above stated intervals. Complete spectra were thus obtained in 240-seconds. Experiment performance was normal for the first month. A short circuit in the high-voltage portion caused the experiment to fail.
831:
above 1.8-MeV plus protons above 21-MeV), and a fission cell (protons above 120-MeV). The latter two instruments were specifically included as prototypes of
Pioneer instruments designed to measure very high fluxes of Jovian trapped particles. As such they were not optimized for measurements of the relatively low fluxes in the Earth's radiation belt. The successful telescope consisted of six colinear sensors (five
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559:
772:, respectively. Corresponding sensitivities were ± 0.06, 0.19, 0.56, and 1.69 nT, respectively. Automatic range selection capability was included. A flipping mechanism permitted inflight calibration of the three sensor zero levels. The vector sampling rate was 12.5 samples per second. The experiment functioned normally through the spacecraft life.
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onboard analog computers. There were 64 logarithmically equispaced frequency channels centered from 23-Hz to 200-kHz with a 15% bandwidth at 3-dB. Averaging time was 2.5-seconds at the high bit rate. The combinations of elements and the sequence of frequencies to be measured were controlled either by an onboard computer or from the ground.
704:
resolution was about 30%. Each E-B channel was sampled every 5.12-seconds. A short back-up dipole antenna (about 1 m (3 ft 3 in) tip to tip) was also used to detect very short wavelength plasma phenomena. Analog B or E data from 0 to 30-kHz in three segments were also telemetered on the special purpose 4-
889:
range 100-keV to 1.5-MeV. Information on protons between 0.5- and 4.0-MeV was also obtained. A collimated stilbene crystal scintillator looking perpendicular to the spacecraft spin axis was the principal detector. A similar, fully shielded crystal served to determine the contribution to the principal
830:
data for comparison with the
Pioneer data in gradient studies. The experiment consisted of a composition telescope (which failed approximately 10 days after launch), a second telescope (from which virtually all the useful data of this experiment were obtained), an electron current detector (electrons
738:
The objective of this experiment was to study the spectra of the galaxy, the sun, and
Jupiter with high flux resolution (about 1%). A radiometer, operating in either a stepping mode (eight frequencies) or at a single frequency, was connected to a 91 m (299 ft) dipole antenna, which was also
632:
were used for the electric fields experiments, and one of these pairs was also used for the Radio astronomy experiment. The members of the antenna pair along the spacecraft spin axis extended 2.9 m (9 ft 6 in), the members of the pair used in both the electric field and radio astronomy
792:
This experiment consisted of two oppositely directed plasma detectors, both of which were normal to the spacecraft spin axis. An electrostatic analyzer measured protons and alpha particles with deflection voltages between 170 and 6400 volts. An electrostatic analyzer and velocity selector measured
646:
Two dipole antennas were mounted orthogonally in the spin plane of the spacecraft while a third dipole antenna was mounted along the spacecraft spin axis. Antenna element lengths were -X, 27.6 m (91 ft); +X, 24.4 m (80 ft); -Y and +Y, 45.5 m (149 ft); -Z and +Z (spin
716:
This experiment was designed to determine the polarization, direction of propagation, flux, and direction of the wave normal surface for plasma waves. The time-averaged correlation at one channel frequency from any combination of the six antenna elements could be simultaneously calculated by six
703:
Three orthogonal loop antennas and the three orthogonal (nearly balanced) dipoles gained simultaneous E and B field data in 16 logarithmically equispaced narrow channels from 20-Hz to 200-kHz. These detectors were also used in the dc electric field (71-019A-02) experiment. The spectral frequency
876:
The solar proton monitoring experiment consisted of five separate detectors, each using one or more solid-state detector elements. Three detectors, each with a 2-pi-sr field of view and a 5.12-seconds accumulation time, measured protons with energies greater than 10-, 30-, and 60-MeV. Resultant
863:
The GSFC cosmic-ray experiment was designed to measure energy spectra, composition, and angular distributions of solar and galactic electrons, protons, and heavier nuclei up to Z=26. Three distinct detector systems were used. The first system consisted of four essentially identical solid-state
747:
This experiment was designed to conduct comprehensive observations of the differential energy spectra, angular distributions, spatial distributions and temporal variations of electrons and protons over the geocentric radial distance range from 1.03 to 30 Earth radii. Two arrays of curved-plate
633:
experiments extended 45.5 m (149 ft), and the members of the third pair were slightly unbalanced, extending 24.4 × 27.6 m (80 × 91 ft), respectively. All four elements perpendicular to the spin axis were to have extended 45.5 m (149 ft).
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axis), 2.9 m (9 ft 6 in). Electrometers measured the analog potential difference between the elements in each pair of antennas simultaneously every 5.12 s. The potential differences were sampled digitally through a 14-bit analog/digital converter every 0.64-seconds. The
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with relatively high time resolution. Two stepped-frequency radiometers, attached to a single 91 m (299 ft) dipole antenna (also used in the electric field experiments), stepped through the frequency range of 30-kHz to 2-MHz in 32 steps.
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experiment was also included in the spacecraft payload. The 16-sided spacecraft was 182.12 cm (71.70 in) high by 135.64 cm (53.40 in) in diameter. The spacecraft spin axis was normal to the
817:
This experiment was designed to measure the spectra and composition of solar and galactic cosmic rays and of magnetotail particles, to serve as a prototype of instruments to be flown on the deep space probes
505:
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per meter. Each channel was sampled once every 5.12-seconds at the high bit rate. The antennas used in the dc field experiment (71-019A-02) were also utilized in this experiment.
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805:(GM) with viewing directions of 170° with respect to the spacecraft spin axis. One tube responded to electrons with energies greater than 20-keV that were backscattered off a
801:
This experiment, which was used to study the acceleration of electrons at the sun and their ejection into interplanetary space, consisted of four detectors. Two of these were
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to electron ratios. Otherwise, the instrument performance was normal until 26 September 1972, when the experiment could not be turned on after a 4-hour spacecraft turnoff.
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analog channel. This experiment was designed to be used in conjunction with the low-energy proton and electron differential energy analyzer (LEPEDEA).
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line. The solar-cell and chemical-battery powered spacecraft carried 2 transmitters. One continuously transmitted PCM encoder data at a 1600
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A hemispherical electrostatic analyzer was used to extend descriptions of the particle (electron and positive ion) populations in the
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768:. The detector was a boom-mounted triaxial fluxgate magnetometer with four ranges: ± 16, 48, 144, and 432
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detector count rate of electrons and protons generated within the principal detector by gamma rays and
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Payloads are separated by bullets ( · ), launches by pipes ( | ). Crewed flights are indicated in
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This experiment, as originally defined by NASA headquarters, has been separated at NSSDC into its
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1279:"Experiment: Interplanetary Long-Wavelength Radio Astronomy Experiment -- Flux Resolution"
1247:"Experiment: Interplanetary Long Wavelength Radio Astronomy Experiment -- Time Resolution"
855:(71-019A-13) and GSFC (71-019A-15) components. Initial experiment performance was normal.
629:
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used in the electric field experiments. The frequency range covered was 0.05 to 3.5-MHz.
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This experiment was designed to study galactic and solar electrons and positrons in the
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This experiment was designed to measure accurately the vector magnetic field in the
725:
This experiment was designed to study the radio spectra of the galaxy, the Sun, and
586:. Its orbit took it to cislunar space during a period of decreasing solar activity.
769:
687:
The AC electric field intensity in 12 narrow channels was measured from 0.1 to 100-
184:
135.64 cm (53.40 in) in diameter by 182.12 cm (71.70 in) high
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the Earth's atmosphere on 2 October 1974, after a highly successful mission.
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1965:
806:
734:
Interplanetary Long-Wavelength Radio
Astronomy Experiment -- Flux Resolution
721:
Interplanetary Long
Wavelength Radio Astronomy Experiment -- Time Resolution
672:
401:
Interplanetary Long-Wavelength Radio
Astronomy Experiment -- Flux Resolution
396:
Interplanetary Long
Wavelength Radio Astronomy Experiment -- Time Resolution
2536:
Symbol indicates failure en route or before intended mission data returned
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2954:
2815:
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1930:
1895:
1471:"Experiment: Nuclear Composition of Cosmic and Solar Particle Radiations"
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1599:"Experiment: Study of Cosmic Ray, Solar, and Magnetospheric Electrons"
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3484:. Payloads deployed from other spacecraft are denoted in (brackets).
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679:(71-019A-16) components. Initial experiment performance was normal.
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625:(VLF) data and for ranging information. Three orthogonal pairs of
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321:
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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This article incorporates text from this source, which is in the
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Explorer 43 continued the study, begun by earlier IMPs, of the
1215:"Experiment: Electrostatic Waves and Radio Noise -- Minnesota"
611:
1119:"Experiment: Electrostatic Waves and Radio Noise (Project)"
813:
Nuclear
Composition of Cosmic and Solar Particle Radiations
431:
Nuclear
Composition of Cosmic and Solar Particle Radiations
1183:"Experiment: Electrostatic Waves and Radio Noise -- Iowa"
1151:"Experiment: Electrostatic Waves and Radio Noise -- GSFC"
881:
451:
Study of Cosmic Ray, Solar, and Magnetospheric Electrons
1439:"Experiment: Medium-Energy Solar Protons and Electrons"
691:. The experiment had an optimum noise threshold of 10
621:
The second transmitter was used for transmission of
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2320:
2209:
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1708:
1701:
1535:"Experiment: Solar and Galactic Cosmic-Ray Studies"
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1635:. Encyclopedia Astronautica. 2011. Archived from
535:. Explorer 43 was launched on 13 March 1971 from
1567:"Experiment: Solar Proton Monitoring Experiment"
712:Electrostatic Waves and Radio Noise -- Minnesota
391:Electrostatic Waves and Radio Noise -- Minnesota
2325:
2329:
2100:
1311:"Experiment: Low-Energy Protons and Electrons"
655:Electrostatic Waves and Radio Noise -- Project
3480:. Uncatalogued launch failures are listed in
2561:
1670:
546:. Explorer 43 was the sixth satellite of the
376:Electrostatic Waves and Radio Noise (Project)
8:
1343:"Experiment: Measurement of Magnetic Fields"
976:
974:
28:
1407:"Experiment: Measurement of Solar Plasma 2"
982:"Trajectory: Explorer 43 (IMP-I) 1971-019A"
699:Electrostatic Waves and Radio Noise -- Iowa
683:Electrostatic Waves and Radio Noise -- GSFC
386:Electrostatic Waves and Radio Noise -- Iowa
381:Electrostatic Waves and Radio Noise -- GSFC
2568:
2554:
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1705:
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659:This experiment, as originally defined by
651:sensitivity was 100 microvolts per meter.
360:
93:
27:
1375:"Experiment: Measurement of Solar Plasma"
1013:
1011:
1009:
797:Medium-Energy Solar Protons and Electrons
426:Medium-Energy Solar Protons and Electrons
1019:"Display: Explorer 43 (IMP-I) 1971-019A"
606:. The initial apogee point lay near the
1503:"Experiment: Radio Astronomy (Project)"
947:
16:NASA satellite of the Explorer program
859:Solar and Galactic Cosmic-Ray Studies
441:Solar and Galactic Cosmic-Ray Studies
7:
3517:Spacecraft launched by Delta rockets
53:Interplanetary Monitoring Platform-6
955:McDowell, Jonathan (21 July 2021).
1695:List of Explorers Program missions
1087:"Experiment: Electrostatic Fields"
872:Solar Proton Monitoring Experiment
574:by measuring energetic particles,
548:Interplanetary Monitoring Platform
531:satellite launched as part of the
483:Interplanetary Monitoring Platform
446:Solar Proton Monitoring Experiment
148:Interplanetary Monitoring Platform
14:
2521:indicates active current missions
512:rocket with Explorer 43 at LC-17A
326:196,574 km (122,145 mi)
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743:Low-Energy Protons and Electrons
537:Cape Canaveral Air Force Station
406:Low-Energy Protons and Electrons
34:
2533:indicate missions yet to launch
752:Measurement of Magnetic Fields
411:Measurement of Magnetic Fields
105:
40:Explorer 43 satellite in space
1:
826:, and to provide reference 1-
788:Measurement of Solar Plasma 2
421:Measurement of Solar Plasma 2
2527:indicates cancelled missions
1051:"Explorer Spacecraft Series"
3512:Spacecraft launched in 1971
776:Measurement of Solar Plasma
416:Measurement of Solar Plasma
176:635 kg (1,400 lb)
167:Goddard Space Flight Center
3533:
598:, and its spin rate was 5
18:
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2514:
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1692:
959:. Jonathan's Space Report
847:Radio Astronomy (Project)
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316:242 km (150 mi)
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192:
188:
127:
123:
57:
33:
663:, has been separated at
243:Douglas Aircraft Company
205:13 March 1971, 16:15:00
19:Not to be confused with
1601:. NASA. 28 October 2021
1569:. NASA. 28 October 2021
1537:. NASA. 28 October 2021
1505:. NASA. 28 October 2021
1473:. NASA. 28 October 2021
1441:. NASA. 28 October 2021
1409:. NASA. 28 October 2021
1377:. NASA. 28 October 2021
1345:. NASA. 28 October 2021
1313:. NASA. 28 October 2021
1281:. NASA. 28 October 2021
1249:. NASA. 28 October 2021
1217:. NASA. 28 October 2021
1185:. NASA. 28 October 2021
1153:. NASA. 28 October 2021
1121:. NASA. 28 October 2021
1089:. NASA. 28 October 2021
1021:. NASA. 28 October 2021
984:. NASA. 28 October 2021
305:Highly elliptical orbit
618:information bit rate.
572:magnetospheric regions
563:
554:Spacecraft and mission
513:
220:(Thor 562 / Delta 083)
23:, also known as IMP-1.
762:Earth's magnetosphere
758:interplanetary medium
562:Explorer 43 satellite
561:
508:
291:Reference system
132:Spacecraft properties
2584:Orbital launches in
642:Electrostatic Fields
371:Electrostatic Fields
119:3.5 years (achieved)
3502:1971 in spaceflight
2989:Soyuz 7K-LOK mockup
1639:on 13 February 2002
803:Geiger–Müller tubes
764:, magnetotail, and
30:
1871:25 (Injun 4, IE-B)
928:Spaceflight portal
675:(71-019A-12), and
623:Very low frequency
602:, with propulsion
564:
514:
286:Orbital parameters
3507:Explorers Program
3489:
3488:
2543:
2542:
2510:
2509:
2449:
2448:
1956:42 (Uhuru, SAS-A)
1686:Explorers Program
936:Explorers program
661:NASA Headquarters
533:Explorers program
503:
502:
463:Explorers program
455:
454:
3524:
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930:
925:
924:
923:
839:sensors and one
366:
361:
312:Perigee altitude
295:Geocentric orbit
197:Start of mission
116:Mission duration
107:
98:
97:
91:
38:
31:
3532:
3531:
3527:
3526:
3525:
3523:
3522:
3521:
3492:
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3490:
3485:
3470:
3446:Intelsat IV F-3
2630:Intelsat IV F-2
2596:
2595:
2585:
2583:
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1100:
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1080:
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1060:
1058:
1055:History of NASA
1049:
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1032:
1024:
1022:
1017:
1016:
1007:
995:
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979:
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906:The spacecraft
904:
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815:
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790:
778:
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591:Radio astronomy
584:magnetic fields
580:electric fields
556:
539:(CCAFS) with a
499:
498:
492:
485:
480:
479:
473:
466:
364:
346:5626.00 minutes
322:Apogee altitude
249:Entered service
219:
145:Spacecraft type
92:
87:
52:
50:
41:
24:
17:
12:
11:
5:
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3398:
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3378:
3371:
3368:Nauka 5KS No.2
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3098:
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3053:
3050:DS-P1-Yu No.33
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3019:
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2762:
2757:
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2737:
2734:Nauka 2KS No.3
2730:
2723:
2720:DS-P1-Yu No.39
2716:
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2207:
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2196:
2189:
2182:
2175:
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2161:
2154:
2151:85–89 (THEMIS)
2147:
2140:
2133:
2128:
2123:
2118:
2111:
2105:
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2097:
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2028:
2023:
2018:
2013:
2008:
2006:52 (Hawkeye 1)
2003:
1998:
1993:
1988:
1983:
1978:
1973:
1968:
1966:44 (Solrad 10)
1963:
1958:
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1948:
1943:
1938:
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1005:
970:
946:
945:
943:
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915:
912:
903:
902:End of mission
900:
887:kinetic energy
882:
879:
873:
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719:
713:
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697:
684:
681:
671:(71-019A-03),
656:
653:
643:
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638:
635:
596:ecliptic plane
568:interplanetary
555:
552:
544:launch vehicle
519:, also called
501:
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273:2 October 1974
271:
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265:End of mission
262:
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229:Cape Canaveral
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140:Explorer XLIII
138:
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15:
13:
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3422:
3419:
3417:
3416:OPS 7898 PL-4
3414:
3412:
3411:OPS 7898 PL-3
3409:
3407:
3406:OPS 7898 PL-1
3404:
3402:
3401:OPS 7898 PL-2
3399:
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3345:Interkosmos 5
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2700:
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2684:
2683:KH-4B No.1113
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2354:
2351:
2349:
2348:76 (TERRIERS)
2346:
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541:Thor-Delta M6
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252:13 March 1971
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66:Space physics
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3441:Molniya 1-19
3373:
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3325:Molniya 2-01
3297:
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3091:Gridsphere B
3087:Gridsphere 2
3083:Gridsphere 1
3048:
3039:Molniya 1-18
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2530:
2519:Green titles
2438:
2431:
2424:
2417:
2365:82 (CHIPSat)
2309:
2302:
2295:
2198:
2191:
2184:
2177:
1960:
1946:40 (Injun 5)
1841:S-66A (BE-A)
1641:. Retrieved
1637:the original
1631:
1625:
1603:. Retrieved
1593:
1571:. Retrieved
1561:
1539:. Retrieved
1529:
1507:. Retrieved
1497:
1475:. Retrieved
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1337:
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1305:
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1177:
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1123:. Retrieved
1113:
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1081:
1059:. Retrieved
1054:
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1023:. Retrieved
986:. Retrieved
961:. Retrieved
957:"Launch Log"
950:
905:
884:
875:
862:
850:
816:
800:
791:
779:
755:
746:
737:
724:
715:
702:
686:
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620:
588:
565:
524:
520:
516:
515:
461:
163:Manufacturer
62:Mission type
25:
3466:Meteor 1-10
3305:Explorer 45
3095:Rigidsphere
3000:Meteor 1-09
2995:Explorer 44
2827:San Marco 3
2800:Meteor 1-08
2740:Explorer 43
2677:Calsphere 5
2672:Calsphere 4
2667:Calsphere 3
2615:Meteor 1-07
2525:Grey titles
2353:79 (HETE-2)
2269:93 (NuSTAR)
2244:81 (RHESSI)
2219:68 (SAMPEX)
2061:61 (Magsat)
2036:56 (ISEE-1)
1926:36 (GEOS-B)
1891:29 (GEOS-A)
1605:14 November
1573:14 November
1541:14 November
1509:14 November
1477:14 November
1445:14 November
1413:14 November
1381:14 November
1349:14 November
1317:14 November
1285:14 November
1253:14 November
1221:14 November
1189:14 November
1157:14 November
1125:14 November
1093:14 November
1025:14 November
988:14 November
963:14 November
760:and in the
637:Experiments
517:Explorer 43
476:Explorer 44
471:Explorer 42
365:Instruments
355:Instruments
332:Inclination
225:Launch site
202:Launch date
173:Launch mass
29:Explorer 43
21:Explorer 18
3496:Categories
3456:Kosmos 470
3451:Kosmos 469
3436:Kosmos 468
3431:Kosmos 467
3426:Kosmos 466
3421:Kosmos 465
3391:Kosmos 464
3386:Kosmos 463
3355:Kosmos 462
3350:Kosmos 461
3340:Kosmos 460
3335:Kosmos 459
3330:Kosmos 458
3320:Kosmos 457
3315:Kosmos 456
3310:Kosmos 455
3283:Kosmos 454
3263:Kosmos 453
3253:Kosmos 452
3243:Kosmos 451
3238:Kosmos 450
3233:Kosmos 449
3228:Kosmos 448
3223:Kosmos 447
3218:Kosmos 446
3213:Kosmos 445
3208:Kosmos 444
3203:Kosmos 443
3198:Kosmos 442
3178:Kosmos 441
3168:Kosmos 440
3163:Kosmos 439
3158:Kosmos 438
3143:Kosmos 437
3138:Kosmos 436
3128:Kosmos 435
3106:Kosmos 434
3101:Kosmos 433
3056:Kosmos 432
3044:Kosmos 431
3022:Kosmos 430
3016:Tselina-OM
3010:Kosmos 429
2976:Kosmos 428
2966:Kosmos 427
2949:Kosmos 426
2939:Kosmos 424
2929:Kosmos 424
2924:Kosmos 423
2919:Kosmos 422
2909:Kosmos 421
2904:Kosmos 420
2899:Kosmos 419
2887:Kosmos 418
2882:Kosmos 417
2877:Kosmos 416
2872:Kosmos 415
2867:Kosmos 414
2862:Kosmos 413
2857:Kosmos 412
2852:Kosmos 411
2847:Kosmos 410
2837:Kosmos 409
2832:Kosmos 408
2822:Kosmos 407
2790:Kosmos 406
2785:Kosmos 405
2780:Kosmos 404
2775:Kosmos 403
2770:Kosmos 402
2760:Kosmos 401
2745:Kosmos 400
2709:Kosmos 399
2704:Kosmos 398
2699:Kosmos 397
2694:Kosmos 396
2689:Kosmos 395
2652:Kosmos 394
2635:Kosmos 393
2620:Kosmos 392
2610:Kosmos 391
2605:Kosmos 390
2249:83 (GALEX)
2229:73 (TRACE)
2193:HelioSwarm
2144:84 (Swift)
2126:78 (IMAGE)
2011:53 (SAS-C)
1996:50 (IMP-J)
1991:49 (RAE-B)
1986:48 (SAS-B)
1981:47 (IMP-H)
1971:45 (SSS-A)
1961:43 (IMP-I)
1951:41 (IMP-G)
1936:38 (RAE-A)
1921:35 (IMP-E)
1916:34 (IMP-F)
1911:33 (IMP-D)
1901:31 (DME-A)
1886:28 (IMP-C)
1876:26 (EPE-D)
1861:23 (S-55C)
1851:21 (IMP-B)
1831:18 (IMP-A)
1821:16 (S-55B)
1816:15 (EPE-C)
1811:14 (EPE-B)
1806:13 (S-55A)
1801:12 (EPE-A)
1716:Explorer 1
942:References
820:Pioneer 10
782:solar wind
693:microvolts
570:and outer
270:Decay date
239:Contractor
181:Dimensions
137:Spacecraft
3478:underline
3028:Apollo 15
2944:Mariner 9
2893:Mariner 8
2795:Tournesol
2714:Shijian I
2641:Apollo 14
2470:Proposals
2463:Proposals
2343:72 (SNOE)
2290:97 (IXPE)
2276:94 (IRIS)
2262:91 (IBEX)
2239:75 (WIRE)
2234:74 (SWAS)
2224:70 (FAST)
2172:96 (ICON)
2165:95 (TESS)
2158:92 (WISE)
2131:80 (WMAP)
2121:77 (FUSE)
2109:69 (RXTE)
2091:67 (EUVE)
2086:66 (COBE)
2071:63 (DE-2)
2066:62 (DE-1)
2056:60 (SAGE)
2046:58 (HCMM)
2021:55 (AE-E)
2016:54 (AE-D)
2001:51 (AE-C)
1941:39 (AD-C)
1906:32 (AE-B)
1881:27 (BE-C)
1866:24 (AD-B)
1856:22 (BE-B)
1846:20 (IE-A)
1836:19 (AD-A)
1826:17 (AE-A)
1786:11 (S-15)
1771:9 (S-56A)
1709:1958–1992
908:reentered
835:-drifted
807:gold foil
673:Minnesota
667:into its
89:1971-019A
83:COSPAR ID
3361:Zenit-2M
3293:OPS 9432
3288:OPS 3431
3278:Prospero
3273:OPS 7616
3248:OPS 4311
3153:OPS 7681
3148:OPS 5454
3122:Zenit-4M
3111:OPS 8607
3005:OPS 8373
2982:Zenit-2M
2971:OPS 8709
2955:Soyuz 11
2842:OPS 3811
2816:Soyuz 10
2810:OPS 7899
2805:Salyut 1
2755:OPS 5300
2750:OPS 4788
2727:Zenit-2M
2662:OPS 5268
2657:Tansei 1
2625:OPS 7776
2359:INTEGRAL
2255:90 (AIM)
2115:71 (ACE)
2081:65 (CCE)
2076:64 (SME)
2051:59 (ICE)
2041:57 (IUE)
1976:46 (MTS)
1751:7 (S-1A)
1702:Missions
1061:30 March
914:See also
896:positron
892:neutrons
853:Michigan
630:antennas
604:Star-17A
527:, was a
510:Delta M6
72:Operator
3482:italics
3461:Oreol 1
3396:Ariel 4
3381:Polaire
3183:Luna 19
3173:Shinsei
3133:Luna 18
3065:LOADS-2
2647:NATO-2B
2531:Italics
2477:FINESSE
2426:SunRISE
2304:TRACERS
2179:SPHEREx
1746:6 (S-2)
1643:19 June
866:nucleon
837:silicon
833:lithium
727:Jupiter
104:SATCAT
3375:Canyon
3268:ITOS-B
3193:TETR-4
3071:OV1-21
3061:OV1-20
2961:SESP-1
2934:Mars 3
2914:Mars 2
2765:ISIS 2
2593:1972 →
2578:← 1970
2502:ESCAPE
2497:EXCEDE
2387:Hitomi
2375:Suzaku
2338:HETE-1
2031:DADE-B
2026:DADE-A
1057:. NASA
627:dipole
576:plasma
342:Period
336:28.70°
301:Regime
233:LC-17A
213:Rocket
3299:STV-4
3258:ASTEX
3188:OSO 7
3079:LCS 4
3033:PFS-1
2492:ASTRE
2487:OHMIC
2482:Arcus
2413:GUSTO
2407:XRISM
2393:NICER
2381:TWINS
2370:CINDI
2297:PUNCH
2101:MIDEX
1791:S-45A
1756:S-46A
706:watts
665:NSSDC
616:bit/s
608:Earth
525:IMP-6
521:IMP-I
495:IMP-H
490:IMP-G
111:05043
51:IMP-6
49:IMP-I
46:Names
3116:Eole
3075:RTDS
2586:1971
2440:CASE
2433:EZIE
2400:GOLD
2322:UNEX
2311:COSI
2283:GEMS
2211:SMEX
2200:UVEX
2186:MUSE
2137:FAME
1796:S-55
1776:S-45
1766:S-56
1645:2018
1607:2021
1575:2021
1543:2021
1511:2021
1479:2021
1447:2021
1415:2021
1383:2021
1351:2021
1319:2021
1287:2021
1255:2021
1223:2021
1191:2021
1159:2021
1127:2021
1095:2021
1063:2019
1027:2021
990:2021
965:2021
822:and
677:GSFC
669:Iowa
582:and
529:NASA
523:and
76:NASA
2419:AWE
1741:S-1
1632:IMP
841:CsI
612:Sun
600:rpm
207:GMT
158:IMP
154:Bus
106:no.
3498::
3093:,
3089:,
3085:,
3081:,
3077:,
2326:MO
1781:10
1053:.
1008:^
973:^
828:AU
824:11
770:nT
689:Hz
649:DC
589:A
578:,
550:.
231:,
3097:)
3073:(
3067:)
3063:(
3035:)
3031:(
2569:e
2562:t
2555:v
2330:I
2328:/
2324:/
1761:8
1736:5
1731:4
1726:3
1721:2
1678:e
1671:t
1664:v
1647:.
1620:.
1609:.
1588:.
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1556:.
1545:.
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1140:.
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1076:.
1065:.
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1029:.
1003:.
992:.
967:.
610:-
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