ORBIT UNCERTAINTY AND SEA-SURFACE ALTIMETRY,

Abstract

The extent to which unknown disturbances in orbit will affect the accuracy of an altimeter-derived geoid is investigated. A simple perturbation scheme is developed to examine the effects of isolated geopotential anomalies on a 600 km satellite in circular polar orbit. Hypothetical geoid undulations representing two different scales of anomalous geopotential are expanded in zonal harmonics. The resulting perturbations are analyzed and contrasted to the sea-surface (geoid) profiles. It is found that short-period fluctuations caused by mesoscale anomalies will amount to a few percent of the undulation amplitude; orbital-period fluctuations are likely to be ten times as large. Strong microscale anomalies such as those correlative to deep ocean trenches will cause disturbances on the order of 1 to 2 cm. It is concluded that with dense tracking (several fixes per revolution) overall errors in geocentric radius can be kept below 1 m; errors in computed orbit will not prevent the detection of sea-surface features of decimeter height, provided their scales are sufficiently small. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1970
Accession Number
AD0705268

Entities

People

  • Frederick C. Jackson

Organizations

  • New York University

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Accuracy
  • Altimeters
  • Altimetry
  • Amplitude
  • Artificial Satellites
  • Deep Oceans
  • Detection
  • Errors
  • Geopotential
  • Harmonics
  • Height
  • Mathematics
  • Orbits
  • Perturbations
  • Polar Orbits
  • Submarine Trenches
  • Undulation

Fields of Study

  • Environmental science

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Space Exploration and Orbital Mechanics.

Technology Areas

  • Space
  • Space - Orbital Debris