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In the design of spacecraft, heat transfer becomes a criterion of operation to maintain structural and equipment integrity over long periods of time. ...In the design of spacecraft, heat transfer becomes a criterion of operation to maintain structural and equipment integrity over long periods of time. The spacecraft thermal balance between cold space and solar, planetary, and equipment heat sources is the means by which the desired range of equipment and structural temperatures are obtained. ...With the total spacecraft balance set, subsystem and component temperatures can be analyzed for their corresponding thermal requirements.

This SAE Metric Aerospace Recommended Practice (MAP) establishes the requirements for preparing a specification for fluid couplings for spacecraft servicing. The objective of this document is to provide design, development, verification, storage, and delivery requirement guidelines for the preparation of specifications for fluid couplings and the ancillary hardware for use with serviceable spacecraft designed for use in the space environment. ...The objective of this document is to provide design, development, verification, storage, and delivery requirement guidelines for the preparation of specifications for fluid couplings and the ancillary hardware for use with serviceable spacecraft designed for use in the space environment. The couplings shall be capable of resupplying storable propellants, cryogenic liquids, and gases to a variety of spacecrafts. ...The couplings shall be capable of resupplying storable propellants, cryogenic liquids, and gases to a variety of spacecrafts.

These neutrons are produced from several sources: from the terrestrial albedo and as secondary particles produced by the interaction of cosmic rays, solar protons and trapped protons with the material of the spacecraft. Recently, neutrons have also been observed originating in solar flares, at the solar surface. ...Theoretical estimates and experimental measurements of the neutron fluxes inside manned spacecraft in near-Earth orbit are reviewed and discussed. The anticipated neutron fluxes and their resulting dose-equivalents, as a function of shielding depth for exploration class missions, are presented and discussed.

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.

The ROSETTA mission is a European Space Agency spacecraft which will rendezvous with the comet Wirtanen. The spacecraft will deploy a Surface Science Package (SSP) to land on the comet. ...Thus, the heater power demand at 5.25 AU has to be low, when the spacecraft is in Deep Space Hibernation mode. Prior to the comet rendezvous, the spacecraft is woken up. ...With a fully operational payload, the ROSETTA spacecraft establishes an orbit around comet Wirtanen. The spacecraft follows the comet during its approach to the sun.

The Thermosphere, Ionosphere, Mesosphere, Energetics, and Dynamics (TIMED) spacecraft is the first science mission in the Solar Terrestrial Probe program sponsored by the NASA Office of Space Sciences and is being developed by the Johns Hopkins University, Applied Physics Laboratory (APL). ...The TIMED spacecraft is a three axis stabilized, nadir pointing, low earth orbit scientific satellite with one side of the spacecraft always pointing away from the sun. ...The TIMED spacecraft is a three axis stabilized, nadir pointing, low earth orbit scientific satellite with one side of the spacecraft always pointing away from the sun. The instruments' fields of view (FOV), pointing accuracy, jitter requirements, anti-sun pointing of one spacecraft side, and sun angle variations during the year place severe limitations on the design configuration of the solar array.

Because MMO is spin-stabilized spacecraft, MMO requires the sun-shield and the radiator-shield in the cruise phase (Earth to Mercury) in which MMO is 3-axis stabilized, to avoid the exposure to the direct solar flux.

The software package for computerized modeling of thermal regimes of a spacecraft (S/C) provided with passive and active means of temperature control, under conditions of orbital flight mission and at thermo-vacuum testing conditions, is represented.

A number of methods for making improvements to optical solar reflectors for passive thermal control of spacecraft have been discussed in previous papers (1, 2). These methods have been evaluated practically in terms of their likely increase in efficiency against the degree of complexity require to incorporate the improvement itself.

ALTAN (ALenia Thermal ANalyser) is a tool developed in Alenia Spazio, for the thermal simulation of satellites. Distinctive features of ALTAN are the description of the system in terms of thermal objects that can be considered as high level primitives, the accurate modelling of the energy sources (planets and sun) and of the optical properties, the integration in a single tool of the steps of radiative, conductive and thermal calculations and of the post-process of the results. An example of ALTAN application is given for Bepi-Colombo mission to Mercury, in particular the modelling of the highly variable planet temperature and the directional optical properties of the planet surface.

A regulated high voltage solar array/battery system using large area silicon solar cells and a group of Ni-H energy storage cells meets the requirements of a multikilowatt geosynchronous orbit application. The electrical power bus operates at approximately 50 Vdc, minimizing unbalanced magnetic torques and distribution harness weight. The program design goal of 12 years of operation on station, including up to 2 years of orbital storage, represents a significant extension of total mission life.

Recent development programmes have demonstrated that considerable improvements in the thermal and mechanical properties of CMX optical solar reflectors (OSRs) can be achieved. Optical coatings have been used to increase infra-red emittance by 4% and to decrease solar absorptance by 50% enabling more efficient thermal control. Another programme aimed at enhancing the mechanical strength of OSRs, has resulted in a chemical process which can increase the glass strength to more than four times its untreated value. This product improvement, in parallel with new automated test equipment for proving the strength of each reflector, should dramatically reduce the numbers damaged during assembly processes and hence provide considerable cost savings.

The Terra spacecraft is the flagship of NASA’s Earth Science Enterprise. It provides global data on the atmosphere, land, and oceans, as well as their interactions with solar radiation and one another. ...Since the launch of the Terra spacecraft in December 1999, each CPHTS has been providing a stable interface temperature specified by the instrument under all modes of spacecraft and instrument operations. ...Since the launch of the Terra spacecraft in December 1999, each CPHTS has been providing a stable interface temperature specified by the instrument under all modes of spacecraft and instrument operations. The ability to change the CPHTS operating temperature upon demand while in service has also extended the useful life of one instrument.

This paper presents application of multi-objective optimization to the design of spacecraft power subsystem. The selection of optimum design can be achieved by having a comparative trade study among different alternatives available. ...The paper provides a methodology to optimize the SEPS (Spacecraft Electrical Power Subsystem) design process taking into account both the technology trades and initial sizing in a constrained environment. ...Then it presents spacecraft power system sizing, which is derived by the mission requirements and design constraints imposed by technology available.

The report presents the results of developing, ground testing and space exploitation of the systems providing the low temperature cooling of the onboard equipment of the spacecraft at stationary and elliptic orbits when it is arbitrarily oriented on the Sun and the planet.

Following the launch aboard a 7925 Delta II, and nearly three years of semi-dormant cruise mode, the NEAR spacecraft will rendezvous with and orbit the near-Earth asteroid 433 Eros. While orbiting 433 Eros, NEAR will conduct the first systematic scientific exploration of an asteroid by measuring its bulk, surface, and internal properties. ...In order to accomplish this task, the NEAR spacecraft contains a suite of sensors comprised of an Infrared (IR) Spectrometer, a Multispectral Imager/Spectrometer, an X-Ray/Gamma-Ray Spectrometer, a Magnetometer, and a Laser Rangefinder. ...The structure supporting these sensors is part of a 3-axis stabilized, solar-oriented spacecraft that employs fixed coplanar solar arrays to provide a constant voltage, regulated power bus.

For the past three decades spacecraft thermal analysis has been predominantly performed using lumped parameter solvers such as ESATAN and SINDA.

The European Space Agency ESA is preparing a mission to planet Mercury called BepiColombo in cooperation with ISAS, the Japanese space agency. Advanced thermal control materials and components are under development to allow the performance of the mission. The present paper gives an overview of the BepiColombo thermal control design and give emphasis to the continued effort in the development of a Solar Reflector Coating (SRC), an Optical Solar Reflector (OSR) and an Infra-Red Rejection Device (IRRD). Key issue in the development and validation of the components and related technologies is the long-term stability under the high temperature and high intensity radiation environment in the vicinity of Mercury. Therefore thermal and radiation endurance testing plays a major role. Candidate materials have been selected and the component design been defined. Development tests will establish mechanical, thermal and optical properties for the initial and end of life conditions.

The mission objective of the TRW satellite requires four solar arrays be deployed simultaneously following separation from the inertial upper stage (IUS) booster. Due to the mechanical system's tolerances, the mass properties control procedure, and in-orbit temperature variation, as well as the potential for satellite tumbling, the possibility of sequential latch-up of flexible solar arrays becomes realistic. To determine the influence of sequential solar array latching on the deployment loads is, therefore, of great practical importance. Although the problem should be treated as a nonstationary stochastic process, the difficulty in obtaining an exact solution renders the process unsuitable. In response, this paper presents a Monte Carlo method for approximating a solution to such a problem.