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Peters, C. F.

Publications and source records attributed to Peters, C. F..

6 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Numerical integration of the satellites of the outer planets

The formulation of a numerical integration program, used to construct ephemerides for satellites of the outer planets, is described. The equations of motion are derived, including (1) n massive integrated satellites, (2) m massive perturbing planets, (3) J2, J4 oblateness coefficients of the primary and each satellite, and (4) a barycentric coordinate system. Variational equations are also found: (1) 6n initial states and n masses of the integrated satellites, (2) J2, J4 of the primary planet, (3) the mass of the system, and (4) right ascension and declination of the pole. The formulation was used to construct the satellite ephemerides of Saturn for the Voyager mission.

Peters, C. F.↗
NASA NTRS1981

Orbits of the small satellites of Saturn

Orbital parameter values determined from Voyager 1 imaging data for the small Saturn satellites 1980S1, 1980S3, 1980S6, 1980S26, 1980S27, and 1980S28 are presented. The dynamic model used for all satellites is a Keplerian ellipse, whose apse and node precess under the influence of the central-body harmonics. In evaluating eccentricity and inclination, it was found that the largest source of error is the difficulty of making measurements when satellites are at, or approaching, transit.

Synnott, S. P.↗
NASA NTRS1975

Eclipses of natural planetary satellites

A general method is given for predicting eclipse events for natural planetary satellites suitable for use on a large scale digital computer. The precision is sufficient to process photometric eclipse observations to improve natural satellite ephemerides. Expected accuracy improvement for Saturn's satellites should be an order of magnitude or better. Predicted eclipse times of satellites by Saturn and the Rings are given for the next decade.

Peters, C. F.↗
NASA NTRS1973

Accuracy analysis of the ephemerides of the Galilean satellites

Known discrepancies between Sampson's Theory and observations of the Galilean satellites produce in plane errors of about 1200 km. Since the mean longitude is responsible for most of the discrepancy a simple time correction may be used to significantly reduce these errors. An analysis of the time corrections derived for Sampson's Theory, concludes that the dominant error in the mean longitudes results from Sampson's definition of time, which was determined by the observations which he used in constructing the theory. Imposition of the libration constraint results in changes to the time corrections which are less than the standard deviation of those quantities. The individual eclipse observational errors are shown to be proportional to the square root of the period. With improved star catalogs, the attainable accuracy of the ephemerides of the Galilean satellites is about 100 km from photographic plates versus about 200 km for eclipse observations.-

Peters, C. F.↗
NASA NTRS1973

Table mountain satellite observations - 1971-72

Reduced photographic plate observations are given for some of the satellites of Jupiter and Saturn. The observations were made with the 24-in. reflector at Table Mountain Observatory in 1971 and 1972, and were corrected for elliptic aberration. The planetary positions were obtained from DE-69 developed at JPL.

Peters, C. F.↗