Vanguard I IGY Satellite (1958 Beta)

Easton, Roger L.; Votaw, M. J.

doi:10.1063/1.1716492

Cited by 49 publications

(9 citation statements)

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“…R. I. Easton and M. J. Votav first reported measurements of the spin rate (14), which coincide with our own measurements ( Fig. 3) in all details during the launching period as well as in spin rate decay during the early life of this satellite.…”

Section: Eddy Current Retardationsupporting

confidence: 82%

Anomalies of the Geomagnetic Retardation of the Spin of Satellite Vanguard I (1958 Beta)

Arendt

1961

ARS Journal

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Continuous observations of the spin rate decay of satellite Vanguard I (Beta 1958) have indicated anomalies that do not fit into the picture developed from the theory of exponential magnetic damping by eddy currents. The first anomaly was detected in December 1958; the decay changed to a very low rate; a rate similar to the previous decay was observed early in 1959. Other anomalies were found later in 1959 and in 1960. Some of the anomalous low decay rates might be related to the movement of the Earth around the sun. During the 2| years of observation the spin changed from 1 revolution in J sec to 1 revolution in 20 sec. The slope of the decay curve varied between 0.19 and 7.6 arbitrary log units during fall 1960; initially the slope varied between 4.1 and 5.0 units. The slope during first anomaly was 2.2 units. Spin FadingT HE METHOD of obtaining the spin rate of an artificial satellite by the counting of maxima or minima in a satellite's CW signal is well known. These "spin fades" are produced by the lobes or zeros in the pattern of the satellite's transmitting antenna. The effects of various types of satellite antennas (such as dipoles, turnstile or slot antennas) have to be considered as well as the influence of the receiver antenna, the polarization of that antenna, and the geometry of and the ionization along the propagation path. For these reasons, the spin fading observations are easily disturbed by other fading phenomena such as multiple path reception or Faraday fading. For example, Sputnik I showed a spin fading period of about 4.6 sec. The period of Faraday fading observed was 4.4 sec at 20 mc and 15.0 sec at 40 mc. Thus, it is sometimes difficult to differentiate both phenomena. However, with frequencies in the order of 100 mc the periods of Faraday fading are in the order of minutes and will not divert spin fading observation. Further, multiple path reception is much less probable with such higher frequencies than in the 20-and 40-mc range. Therefore, the observations of Vanguard I on 108 mc are rather free from errors due to other types of fading.When a satellite is placed into orbit, the effects of gravity are greatly reduced in the sense that the satellite can be considered a free gyroscope and under no constraint. Therefore, small forces become effective. Torques acting at the spin axis produce a decay of the spin rate. Other small torques not aligned along the spin axis cause precession and lead to tumbling. Such tumbling or precession period causes a complicated rotation of the antenna pattern with respect to the observer on Earth. The resulting ambiguity in the interpretation of the data is demonstrated by Fig. 1, which shows the spin and precession fades during the early life of Vanguard I. The ambiguity was solved in this case by independent telemetry signals measuring the initial spin before third-state separation during the launching operation. 2 The author is indebted to R. I. Easton and M. J. Votav for this communication.Many authors have described the relationship between the radiation...

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Section: Eddy Current Retardationsupporting

confidence: 82%

Anomalies of the Geomagnetic Retardation of the Spin of Satellite Vanguard I (1958 Beta)

Arendt

1961

ARS Journal

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“…This progress was only possible because the people involved had a good understanding of quantum processes [13] while they were developing the necessary manufacturing techniques. In a few years, silicon-based photovoltaic cells were developed with a PCE of 15%, which made the first practical application possible, including, in 1958, the artificial satellite Vanguard I, the first large-scale equipment furnished with silicon photovoltaic cells [14]. In the last sixty years, silicon technology has progressed up to an efficiency of about 26.7% on small cells ( Figure 1b) and 24.4 % on large photovoltaic modules [3].…”

Section: Silicon (Si)mentioning

confidence: 99%

The History of Photovoltaics with Emphasis on CdTe Solar Cells and Modules

2020

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Among thin-film photovoltaic technology, cadmium telluride (CdTe) has achieved a truly impressive development that can commercially compete with silicon, which is still the king of the market. Solar cells made on a laboratory scale have reached efficiencies close to 22%, while modules made with fully automated in-line machines show efficiencies above 18%. This success represents the result of over 40 years of research, which led to effective and consolidated production processes. Based on a large literature survey on photovoltaics and on the results of research developed in our laboratories, we present the fabrication processes of both CdTe polycrystalline thin-film solar cells and photovoltaic modules. The most common substrates, the constituent layers, their interaction, the interfaces and the different “tricks” necessary to obtain highly efficient devices will be analyzed. A realistic industrial production process will be analytically described. Moreover, environmental aspects, end-of-life recycling and the life cycle assessment of CdTe-based modules will be deepened and discussed.

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“…SPACE PV CELLS Photovoltaic solar generators have been and will remain the best choice for providing electrical power to satellites. In 1958, US satellite Vanguard 1 demonstrated the first application [38]. After years of moderate growth of the space PV market, the evolution of large scale applications has increased in the late nineties, where the main applications are dominated by the telecommunication satellites, military satellites, and scientific space probes.…”

Section: Quantum Dots (Qds)mentioning

confidence: 99%

PV Technology - Industry update

Chaar

Lamont

El‐Zein³

2010

IEEE PES General Meeting

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This paper is an industrial update on the development of Photovoltaic (PV) Technology. It highlights the three major current types of PV: Crystalline, Thin Film and Nanotechnology. The aim of the development in PV technology is to improve the efficiency of the cells while reducing the production cost of the modules. This variety of PV technologies is still under development to enhance the deployment of solar energy for a greener environment. Space PV Cell technology was also described and the progress in this field is expanding.

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Vanguard I IGY Satellite (1958 Beta)

Cited by 49 publications

References 0 publications

Anomalies of the Geomagnetic Retardation of the Spin of Satellite Vanguard I (1958 Beta)

Anomalies of the Geomagnetic Retardation of the Spin of Satellite Vanguard I (1958 Beta)

The History of Photovoltaics with Emphasis on CdTe Solar Cells and Modules

PV Technology - Industry update

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