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Neilson, R. A.

Publications and source records attributed to Neilson, R. A..

TOPEX watershed coming in oceanography

The NASA Ocean Topography Experiment (TOPEX) will use precision radar altimetry to determine topographic features of the global oceans from which currents may be deduced. TOPEX will coincide with the World Ocean Circulation Experiment (WOCE), which will be conducted at the end of this decade and shall involve ships, fixed and drifting buoys, aircraft observations, and satellite remote sensing, to resolve fundamental questions about the flow of water in the global ocean. TOPEX will contribute to WOCE the measurement of satellite height above the sea surface, and the precise radial position above a reference ellipsoid for the earth. The combination of these two measurements with the marine geoid yields the topographic data sought. Three years of topographic data, together with conventional oceanographic data and theoretical ocean models, will be needed to derive the mean and variable components of ocean circulation.

Cleven, G. C.↗

Mission design for SEASAT-A, an oceanographic satellite

SEASAT-A is a NASA earth satellite for measuring global ocean dynamics from space. Launch is planned for May 1978. The instruments on the spacecraft will provide data on wave height and direction, surface wind speed and direction, ice fields, ocean surface topography and weather. This paper is concerned with the mission design for SEASAT-A. A primary topic here is the selection of the orbit which best satisfies the measurement objectives of the various instruments. The maintenance of this orbit under drag and other perturbations is discussed. The design of the mission profile is outlined. Finally precision orbit determination for SEASAT-A is discussed since it is required to maximize ocean topography accuracy.

Cutting, E.↗

Mariner Mars 1971 adaptive mission planning.

A formal mission-planning process was developed for the Mariner Mars 1971 missions to allow large-scale mission-plan changes based upon flight experience. A modular approach was taken to the definition of requirements and constraints for elements of the mission. A set of rules for combining these modules was established. The concept of a standard mission day was developed in order to provide a consistent time framework for operations. The resulting process allowed for major mission revisions after the failure of Mariner 8 and again after a dust storm had obscured Mars. It allowed adaptive science planning on a short-term turnaround basis throughout the mission.

Haynes, N. R.↗

Mariner 4 - a point of departure.

Mariner IV spacecraft details noting mission profile and requirements, design goals and use of redundancy for reliability increase

MARINER IV SPACE PROBE↗