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Jefferys, W. H.

Publications and source records attributed to Jefferys, W. H..

30 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

New treatment of the critical argument in resonance problems

Traditional methods for isolating the critical argument in Hamiltonian mechanics involve the introduction of a special set of action variables which are both complicated in form and arbitrary in nature. The new variables are in general obscure in their interpretation. This paper introduces a new canonical system corresponding to the original one, but with one more degree of freedom, in which all the variables of the original Hamiltonian can be treated on the same footing. It appears to have significant advantages for machine calculations.

Jefferys, W. H.↗
NASA NTRS1975

Theory of Enceladus and Dione

A new theory of the motion of Enceladus and Dione is under development. The theory is in literal form, with all constants and parameters appearing explicitly, and is being computed with the aid of the algebraic manipulation system TRIGMAN. The development of the disturbing function; the elimination of the short-period terms; and the resonant Hamiltonian and the constants of integration are discussed. An important feature is that the programs have been written in such a manner that, with only minor modification, they should be able to develop the theories of Mimas-Tethys and Titan-Hyperion as well.

Jefferys, W. H.↗
NASA NTRS1975

The theory of Enceladus and Dione - An application of computerized algebra in dynamical astronomy

The orbits of the satellites of the outer planets are poorly known, due to lack of attention over the past half century. We have been developing a new theory of Saturn's satellites Enceladus and Dione which is literal (all constants of integration appear explicitly), canonically invariant (the Hori-Lie method is used), and which correctly handles the eccentricity-type resonance between the two satellites. The algebraic manipulations are being performed using the TRIGMAN formula manipulation language, and the programs have been developed so that with minor modifications they can be used on the Mimas-Tethys and Titan-Hyperion systems.

Jefferys, W. H.↗
NASA NTRS1974

Stability regions for quasiperiodic motion in the restricted problem of three bodies

Surfaces of section, plotted in configuration space, have been computed for the motion of the massless particle in the restricted problem of three bodies. Nine mass ratios and a wide variety of Jacobi constants were investigated; over four thousand orbits were computed, about half of which were finally used. The plots of surface of section have been reduced to plots of stability regions, following a method due to Henon (1965a, 1965b, 1966b, 1969). Sample surfaces of section are also given. The complete set of 276 surfaces of section has been published as a report (Jefferys, 1971) and is available upon request from the author.

Jefferys, W. H.↗
NASA NTRS1974

The theory of Enceladus and Dione: An application of computerized algebra in dynamical astronomy

A theory of Saturn's satellites Enceladus and Dione is discussed which is literal (all constants of integration appear explicitly), canonically invariant (the Hori-Lie method is used), and which correctly handles the eccentricity-type resonance between the two satellites. Algebraic manipulations are designed to be performed using the TRIGMAN formula manipulation language, and computer programs were developed so that, with minor modifications, they can be used on the Mimas-Tethys and Titan-Hyperion systems.

Jefferys, W. H.↗
NASA NTRS1972

A precompiler for the formula manipulation system TRIGMAN.

Discussion of a translator designed to simplify the programming of problems involving the TRIGMAN formula manipulation system. The translator allows for the introduction of a new data type, SERIES, into a FORTRAN program and translates a user's program into legal FORTRAN. The translator is adaptable to other formula manipulation systems presently used in celestial mechanics.

Jefferys, W. H.↗
NASA NTRS1972

Further periodic solutions of the three-dimensional restricted problem. II.

Discrepancies between a previous paper on the subject by the authors and work by Kozai are investigated. More accurate figures are presented for 23 values of the mean motion, giving combinations of eccentricity and inclination which can be continued to periodic three-dimensional orbits.

Jefferys, W. H.↗