Book contents
- Frontmatter
- Contents
- Dedication
- Preface
- List of Acronyms
- 1 Launch vehicles
- 2 The transfer orbit
- 3 The geostationary orbit
- 4 The satellite environment
- 5 Structures
- 6 Mechanisms
- 7 Thermal control
- 8 Power supply and conditioning
- 9 Propulsion and orbit control
- 10 Attitude stabilization, measurement and control
- 11 Telemetry, tracking and command (TT&C)
- 12 Communications payload
- 13 Meteorological payload
- 14 Product assurance
- 15 Spacecraft development and testing
- Index
4 - The satellite environment
Published online by Cambridge University Press: 02 February 2010
- Frontmatter
- Contents
- Dedication
- Preface
- List of Acronyms
- 1 Launch vehicles
- 2 The transfer orbit
- 3 The geostationary orbit
- 4 The satellite environment
- 5 Structures
- 6 Mechanisms
- 7 Thermal control
- 8 Power supply and conditioning
- 9 Propulsion and orbit control
- 10 Attitude stabilization, measurement and control
- 11 Telemetry, tracking and command (TT&C)
- 12 Communications payload
- 13 Meteorological payload
- 14 Product assurance
- 15 Spacecraft development and testing
- Index
Summary
Introduction
From launch onwards, the quality of life of a satellite is abysmal. During the ascent phase it is subjected to violent acceleration, vibration, shock and decompression which stretch its endurance to the limit - and that is only the beginning of a satellite's troubles.
On earth, vacuum is employed to extend the storage life of foodstuffs. Out in space, vacuum has the opposite effect on satellites, for it shortens their lifespan. In the absence of an atmosphere, they are bombarded with charged particles and exposed to ultraviolet radiation. Different parts of a satellite reach temperature extremes at the same time and, because there is no temperature exchange through convection, such extremes cause structural stress leading to possible malfunction. The particle bombardment gives rise to electrostatic discharge which produces short or open circuits and burns out electronic components. Lubricants evaporate in vacuum and cause moving parts to seize up. Paints and sealants “outgas” (perspire) and settle on sensitive optical surfaces. Micrometeorites travel unimpeded through space and strike satellites with tremendous impact.
Fortunately, a satellite's environment is largely predictable. Much of the time and money spent on building a spacecraft goes on verifying its resilience against a known environment through elaborate quality control and testing. In this chapter we shall explore the environment surrounding a geostationary satellite during all its phases of flight.
Powered Flight Loads
During the ascent phase, a satellite is subject to compression forces due to quasi-static acceleration.
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- Chapter
- Information
- The Geostationary Applications Satellite , pp. 65 - 72Publisher: Cambridge University PressPrint publication year: 1988