NASA Scientific and Technical Aerospace Reports
NASA Scientific and Technical Aerospace Reports
NASA Scientific and Technical Aerospace Reports
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Over the last few decades, significant knowledge has been gained in how to protect spacecraft from charging; however,<br />
the continuing technical advancement in the design <strong>and</strong> build of satellites requires on-going effort in the study of spacecraft<br />
charging. A situation that we have encountered is that not all satellite designers <strong>and</strong> builders are familiar with the problem of<br />
spacecraft charging. The design of a satellite involves many talented people with diverse backgrounds, ranging from<br />
manufacturing <strong>and</strong> assembly to engineering <strong>and</strong> program management. The complex design <strong>and</strong> build of a satellite system<br />
requires people with highly specialized skills such that cross-specialization is often not achievable. As a result, designers <strong>and</strong><br />
builders of satellites are not usually familiar with the problems outside their specialization. This is also true for spacecraft<br />
charging. Not everyone is familiar with the definition of spacecraft charging <strong>and</strong> the damage that spacecraft charging can<br />
cause. Underst<strong>and</strong>ing the problem is an important first step in getting everyone involved in addressing the appropriate<br />
spacecraft charging issues during the satellite design <strong>and</strong> build phases. To address this important first step, an educational<br />
multimedia presentation has been created to inform the general engineering community about the basics of spacecraft<br />
charging. The content of this educational presentation is based on relevant published technical papers. The presentation was<br />
developed using Macromedia Flash. This software produces a more dynamic learning environment than a typical slide show<br />
, resulting in a more effective learning experience. The end result is that the viewer will have learned about the basics of<br />
spacecraft charging. This presentation is available to the public through our website, www.dplscience.com, free of charge.<br />
Viewers are encouraged to pass this presentation to colleagues within their own work environment. This paper describes the<br />
content of the multimedia presentation.<br />
Author<br />
Educational Resources; Multimedia; Spacecraft Charging<br />
20040111045 York Univ., Toronto, Ontario, Canada<br />
Effects of Large-Amplitude RF Emissions on OEDIPUS-C Floating Voltages<br />
Laframboise, J. G.; Wallis, D. D.; James, H. G.; 8th Spacecraft Charging Technology Conference; March 2004; 13 pp.; In<br />
English; See also 20040111031<br />
Contract(s)/Grant(s): NSERC-A-4638; No Copyright; Avail: CASI; A03, Hardcopy<br />
The TCM voltmeter experiment on the OEDIPUS-C tethered payload provided a unique opportunity to compare the<br />
charging of two geometrically similar spacecraft, one of which carried a high-voltage RF transmitter. The data from this<br />
experiment, together with measurements of ambient plasma parameters from other onboard instruments, have permitted<br />
stringent testing of available theories for electron collection by strongly driven antennas in the space plasma. Earlier simple<br />
theories have predicted that a transition occurs from rectification-dominated electron collection at low frequencies, causing the<br />
spacecraft’s floating potential to be driven negative, to ponderomotive-dominated collection at higher frequencies, causing this<br />
potential to be driven positive. Our calculation incorporates a model of a transition between these two cases as the frequency<br />
increases.<br />
Author<br />
Electric Potential; Payloads; Tethering; Spacecraft Charging; Radio Frequencies; Emission; Amplitudes<br />
20040111046 European Space Agency. European Space Research <strong>and</strong> Technology Center, ESTEC, Noordwijk, Netherl<strong>and</strong>s<br />
Investigation of Electrostatic Potential Barrier Near an Electron-Emitting Body<br />
Thiebault, Benoit; Hilgers, Alain; Sasot, Eloy; Forest, Julien; Genot, Vincent; Escoubet, Philippe; 8th Spacecraft Charging<br />
Technology Conference; March 2004; 8 pp.; In English; See also 20040111031; No Copyright; Avail: CASI; A02, Hardcopy<br />
Electrons emitted on spacecraft surfaces can generate negative potential barriers. This may affect the equilibrium potential<br />
of the spacecraft, which can be driven more negative <strong>and</strong> jeopardize plasma measurements by repelling low energy particles.<br />
This phenomenon is investigated with the help of a numerical method based on the turning point formalism to classify orbits<br />
<strong>and</strong> which is validated with a PIC code. Comparison with spacecraft data in the magnetosphere is performed.<br />
Author<br />
Electrostatics; Spacecraft Charging; Electric Potential; Electron Emission<br />
20040111050 <strong>NASA</strong> Glenn Research Center, Clevel<strong>and</strong>, OH, USA<br />
New <strong>NASA</strong> SEE LEO Spacecraft Charging Design Guidelines: How to Survive in LEO Rather than GEO<br />
Ferguson, Dale C.; Hillard, G. Barry; 8th Spacecraft Charging Technology Conference; March 2004; 7 pp.; In English; See<br />
also 20040111031; No Copyright; Avail: CASI; A02, Hardcopy<br />
It has been almost two solar cycles since the GEO Guidelines of Purvis et al (1984) were published. In that time, interest<br />
in high voltage LEO systems has increased. The correct <strong>and</strong> conventional wisdom has been that LEO conditions are<br />
32
Change language