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The MUSES-B spacecraft will be launched in 1996 by the Institute of Space and Astronautical Science (ISAS). ...The thermal design and verification has been performed separately for the major modules of the spacecraft; a main structure, a deployable antenna and Reaction Control System (RCS). Special attention is paid to the exposed RCS whose solar input varies significantly depending on the sun angle.

Radarsat is a Canadian remote sensing satellite designed to gather earth resource data from a low earth orbit. The spacecraft consists of four major entities: the payload module, the bus module, the SAR antenna and the solar arrays.

A novel direct acoustic test was performed on the Quik- SCAT spacecraft at Ball Aerospace Technology Corporation (BATC) in Boulder, Colorado, in October 1998. ...The QuikSCAT spacecraft was designed and built by BATC in an accelerated, one-year, program managed by the NASA Goddard Space Flight Center. ...The QuikSCAT spacecraft was designed and built by BATC in an accelerated, one-year, program managed by the NASA Goddard Space Flight Center. The spacecraft carries the SeaWinds scatterometer developed by the Jet Propulsion Laboratory to measure the near-surface wind speed over Earth’s oceans.

Most interestingly, the relative state errors are significantly less than the individual errors in the two spacecraft absolute states and that the technique is virtually immune to refraction and relativistic effects.

Also described are the primary mission objective, the spacecraft configuration, requirements and design drivers, mission environments, and design parameters.

In 1998, the first element of the Earth Observing System, the EOS-AM1 spacecraft, will be launched into a sun-synchronous polar orbit. The EOS-AM1 platform will include five instruments that will form the payload used to provide information on global climate change. ...The EOS-AM1 platform will include five instruments that will form the payload used to provide information on global climate change. The spacecraft will also include a dual frequency (Ku- and S-band) High Gain Antenna (HGA) which will serve as the primary system for transmitting the science data and spacecraft telemetry & command data to the ground via the TRDSS (Tracking and Data Relay Satellite System) network. ...The spacecraft will also include a dual frequency (Ku- and S-band) High Gain Antenna (HGA) which will serve as the primary system for transmitting the science data and spacecraft telemetry & command data to the ground via the TRDSS (Tracking and Data Relay Satellite System) network.

A need exists for a controlled, clean rigidization technology to harden inflatable spacecraft once they have achieved the required shape. This study addressed the space environment for typical orbits, development of UV curing cationic epoxy resin systems, mechanical properties of UV cured composites, and fabrication of demonstration tubes using the photocurable resin technology.

The primary challenges are efficient conversion of power from the spacecraft power bus to these low voltages and distribution of the very high accompanying currents within the payload while maintaining proper voltage regulation (typically +/− 5%).

The ISAS's space VLBI satellite HALCA was successfully launched in February 1997. The spacecraft HALCA consists of a box shaped main structure and a large deployable mesh antenna with 8 m effective diameter. ...The integrated spacecraft with the mesh structure antenna is so large and complex that the thermal design and tests had been performed separately for the main structure and the large antenna. ...No thermal vacuum test had been conducted in the fully integrated spacecraft configuration. The complex heat exchange between the antenna and the main structure had been taken into account in the numerical thermal analysis.

A brief description of the NASA Applications Technology Satellite Program and the basic design features of the ATS-F and -G spacecraft, the latest in the series, is presented. The Applications Technology Satellites F and G will be geostationary platforms for conducting a number of communication technology experiments. ...The main feature of these spacecraft is a 30-foot parabolic deployable antenna which can be precisely pointed (0.1°). Descriptions of the technology experiments planned for ATS-F are included to illustrate some of the objectives of the ATS program.

The thermal design of a high-power C-band phased array with integral solid-state amplifiers, and its integration into a three-axis-stabilized spacecraft, are discussed. A thermal design has been developed employing fixed-conductance heat pipes and an embedded heat pipe radiator panel. ...Thermal test verification issues and concerns with 1-g operation in integrated spacecraft testing are also addressed.

Spacecraft attitude control provides the basic stability so that sensors, solar panels, antennas and other hardware are properly oriented to perform their functions. ...A Horizon scanner can automatically seek the earth horizon by detecting the sharp discontinuity in InfraRed intensity at the outer edge of the Earth's mesopause for purposes of a spacecraft's orientation and control. As a satellite in a Low Earth Orbit (LEO) and three-axis stabilized, the Canadian satellite RADARSAT-1 is equipped with two horizon scanners (HS) in order to scan dynamically across the Earth's disc and to establish the attitude relative to the Earth.

The TOPEX/POSEIDON spacecraft is scheduled for launch in June 1992 aboard an Ariane 42P vehicle. The TOPEX/POSEIDON mission is a collaborative scientific venture between NASA and CNES. ...The satellite consists of two major elements, the Multimission Modular Spacecraft bus and the Instrument Module. The IM accommodates seven instruments, the solar array, three communication antennae, and a variety of satellite support equipment. ...This paper describes the primary mission objective, the overall spacecraft configuration, the IM requirements and design drivers, the mission environments, the IM design parameters and approach, the IM thermal design, and the analytical temperature predictions versus requirements.

The FM 15 spacecraft launched in January 1989 is identical in all respects to the FM 13 spacecraft launched in May 1988, except for the addition of three interconnection heat pipes on the external surface of the antenna panel. ...So this flight experiment is unique, because it allows a direct in-flight comparison between two identical spacecraft, one with, and one without heat pipes. Detailed thermal mathematical models have been developed to correlate the anticipated results obtained from INTELSAT V - FM 13 and FM 15 with those obtained from flight telemetry and to verify the level of heat transfer coefficients of the heat pipes.

They will include spacecraft such as the planned Space Station and large antenna/reflector structures for communications and observations. ...Concepts for construction of these spacecraft on orbit and their materials of construction provide some unique research challenges.

The fluctuation of the distance of test masses inside 3 spacecraft’s which are located 5·106km apart is measured with an accuracy of 10−12m to achieve this. ...Variations of solar constant, dissipation and the response to switching/mode changes cause temperature fluctuations that have to be suppressed. The spacecraft thermal design relies on a solar array as a sun shield with good thermal de-coupling between the solar cells and the structure and rejection of heat from the electronics directly to space.

We are developing a wireless multi-channel measurement system in order to measure temperatures during thermal vacuum tests of spacecraft, accelerations during vibration tests, etc. As a developing measurement system, we introduce the prototype model of the wireless temperature measurement system.

The S/C consists of an Instrument Module, which houses the primary instruments and S/C support equipment, and the Multimission Modular Spacecraft Standard Bus. The thermal design of the S/C includes multi-layer insulation, fixed radiators, shielded and unshielded louvers, constant-conductance heat pipes, and thermostatically and proportionally controlled heaters. ...During this time period, the spacecraft experienced initial checkout and instrument turn-on, various orbital adjustment maneuvers, and normal operational modes over a wide range of environmental conditions.

Travelling Wave Tubes (TWT) and klystrons respectively are two of the most important components for communication and earth research spacecraft. Actual requirements have led to TWT's with a heat dissipation up to 600 W (≃ 350 W RF).

As an introduction, the paper shows that for spacecraft systems to be designed for the next generation of scientific missions, the system complexity and long life requirements produce reliability criteria which can not be met by either current satellite logic circuitry nor application of redundant sets of such circuitry.