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Vinti, J. P.

Publications and source records attributed to Vinti, J. P..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Quadrature solution for the general relativistic motion of a satellite or a planet.

The general relativistic motion of a particle in a bounded orbit around a central mass M is derived with the aid of the Schwarzschild field of M. A quadrature gives the central angle as a quasi-periodic function of an effective true anomaly. The mean rate of advance of the pericenter is investigated. Classical and general relativistic orbiters with the same initial conditions are compared, taking into account the treatment of the general relativistic effect by means of a differential correction. General relativistic variations are discussed, giving attention to the variation of the eccentric anomaly and the variation of the central angle.

Vinti, J. P.↗
NASA NTRS1973

Gaussian variational equations for osculating elements of an arbitrary separable reference orbit.

Lagrange-type equations are often used in planetary theory and sometimes in satellite theory. The equations express the variation of osculating Keplerian elements in terms of derivatives of a disturbing function or a perturbing potential. When the perturbing force is derivable from a potential, it is possible to convert the Lagrange-type equations to another form. This form, usually, attributed to Gauss, contains the perturbing forces instead of the derivatives of the potential. The case of an arbitrary separable reference orbit is discussed together with a lemma, a Keplerian check, and questions of the applicability of the equations to the spheroidal method.

Vinti, J. P.↗
NASA NTRS1972

Theory of an experiment in an orbiting space laboratory to determine the gravitational constant.

An experiment is discussed for determining the gravitational constant with the aid of an isolated system consisting of an artificial satellite moving around an artificial planet. The experiment is to be conducted in a spherical laboratory traveling in an orbit around the earth. Difficulties due to the gravity-gradient term are considered, and the three-tunnel method proposed by Wilk (1969) is examined. The rotation of the sphere is discussed together with aspects of the reference systems used, the equations of motion of the spacecraft and of the test objects, the field from the earth's gravity gradient at the test object, higher harmonic terms in the gravity gradient force, gravitational effects of the spacecraft itself, and a computer simulation.

Vinti, J. P.↗
NASA NTRS1971

Representation of the earth's gravitational potential.

The paper represents the earth's gravitational potential V, outside a sphere bounding the earth, by means of its difference from the author's spheroidal potential. The difference is in turn represented as arising from a surface density on the sphere bounding the earth. Because of the slow decrease with order n of the normalized coefficients in the spherical harmonic expansion of V, the density anomalies from which the higher coefficients arise must occur in regions close to the earth's surface. The surface density is thus an idealization of the product of the density anomaly and the crustal thickness. Values of surface density are computed from potential coefficients obtained from two sources, Rapp and the Smithsonian Astrophysical Observatory. The two sources give qualitative agreement for the values of surface density and for its contour map. The numerical values obtained for surface density are compatible with the idea that the responsible density anomalies are reasonably small, i.e., less than 0.05 g/cu cm, and occur in the crust alone.

Vinti, J. P.↗