INVESTIGATION OF PHYSICAL PHENOMENA FOR THE NAVIGATION OF SPACE VEHICLES AND EARTH SATELLITES
Abstract
DATA ON PHASES, SPECTRAL DISTRIBUTION, SIZE AND FIGURE OF THE MOON, AND THE INTENSITY OF Lyman alpha reflected from the moon are presented. Preliminary design and peration of an automatic sextant for use in interplanetary vehicles is discussed. The sextant is capable of MEASURING ANGLES, USUALLY NOT EXCEEDING 5 DEGREES, ITH A PRECIPATION OF 0.2 SECONDS. Various aspects of satellite navigation by terrestrial occultations of stars are discussed. A condition for occultation in terms of stellar coordinates and the orbital elements of the satellite is derived. Also an occultation equation relating the time of occultation to the orbital elements is derived. The expected frequency of occultations is discussed. A method of virtual occultation using extinction of starlight in the atmosphere is discussed. An error of approximately 1/2 km in the satellite position measurement is anticipated due to unpredictable variations of atmospheric density. Finally the interference due to the brightness of earth's atm sphere is discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1962
- Accession Number
- AD0291848
Entities
People
- Ali M. Naqvi