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Principles of X-ray Navigation [electronic resource].

Published:
Washington, D.C. : United States. Dept. of Energy, 2006.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
Physical Description:
234 pages : digital, PDF file
Additional Creators:
Stanford Linear Accelerator Center, United States. Department of Energy, and United States. Department of Energy. Office of Scientific and Technical Information
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Summary:
X-ray navigation is a new concept in satellite navigation in which orientation, position and time are measured by observing stellar emissions in x-ray wavelengths. X-ray navigation offers the opportunity for a single instrument to be used to measure these parameters autonomously. Furthermore, this concept is not limited to missions in close proximity to the earth. X-ray navigation can be used on a variety of missions from satellites in low earth orbit to spacecraft on interplanetary missions. In 1997 the Unconventional Stellar Aspect Experiment (USA) will be launched as part of the Advanced Research and Global Observation Satellite (ARGOS). USA will provide the first platform for real-time experimentation in the field of x-ray navigation and also serves as an excellent case study for the design and manufacturing of space qualified systems in small, autonomous groups. Current techniques for determining the orientation of a satellite rely on observations of the earth, sun and stars in infrared, visible or ultraviolet wavelengths. It is possible to use x-ray imaging devices to provide arcsecond level measurement of attitude based on star patterns in the x-ray sky. This technique is explored with a simple simulation. Collimated x-ray detectors can be used on spinning satellites to provide a cheap and reliable measure of orientation. This is demonstrated using observations of the Crab Pulsar taken by the high Energy Astronomy Observatory (HEAO-1) in 1977. A single instrument concept is shown to be effective, but dependent on an a priori estimate of the guide star intensity and thus susceptible to errors in that estimate. A star scanner based on a differential measurement from two x-ray detectors eliminates the need for an a priori estimate of the guide star intensity. A first order model and a second order model of the two star scanner concepts are considered. Many of the stars that emit in the x-ray regime are also x-ray pulsars with frequency stability approaching a part in 10⁹. By observing these pulsations, a satellite can keep accurate time autonomously. They have demonstrated the acquisition and tracking of the Crab nebula pulsar by simulating the operation of a phase-locked loop.
Report Numbers:
E 1.99:slac-r-809
slac-r-809
Subject(s):
Other Subject(s):
Note:
Published through SciTech Connect.
03/17/2006.
"slac-r-809"
Hanson, John Eric.
Funding Information:
AC02-76SF00515
View MARC record | catkey: 13823497