A multimission three-axis stabilized spacecraft flight dynamics ground support system

The Multimission Three-Axis Stabilized Spacecraft (MTASS) Flight Dynamics Support System (FDSS) has been developed in an effort to minimize the costs of ground support systems. Unlike single-purpose ground support systems, which attempt to reduce costs by reusing software specifically developed for previous missions, the multimission support system is an intermediate step in the progression to a fully generalized mission support system in which numerous missions may be served by one general system. The benefits of multimission attitude ground support systems extend not only to the software design and coding process, but to the entire system environment, from specification through testing, simulation, operations, and maintenance. This paper reports the application of an MTASS FDSS to multiple scientific satellite missions. The satellites are the Upper Atmosphere Research Satellite (UARS), the Extreme Ultraviolet Explorer (EUVE), and the Solar Anomalous Magnetospheric Particle Explorer (SAMPEX). Both UARS and EUVE use the multimission modular spacecraft (MMS) concept. SAMPEX is part of the Small Explorer (SMEX) series and uses a much simpler set of attitude sensors. This paper centers on algorithm and design concepts for a multimission system and discusses flight experience from UARS

MAST: a mass spectrometer telescope for studies of the isotopic composition of solar, anomalous, and galactic cosmic ray nuclei

The mass spectrometer telescope (MAST) on SAMPEX (Solar, Anomalous, and Magnetospheric Particle Explorer) is designed to provide high-resolution measurements of the isotopic composition of energetic nuclei from He to Ni (Z=2 to 28) over the energy range from ~10 to several hundred MeV/nucleon. During large solar flares MAST will measure the isotopic abundances of solar energetic particles to determine directly the composition of the solar corona, while during solar quiet times MAST will study the isotopic composition of galactic cosmic rays. In addition, MAST will measure the isotopic composition of both interplanetary and trapped fluxes of anomalous cosmic rays, believed to be a sample of the nearby interstellar medium

Mission Operations Report (MOR) for the Solar, Anomalous, and Magnetosphere Particle Explorer (SAMPEX)

MISSION OPERATIONS REPORTS are published for use by NASA senior management, as required by NASA Headquarters Management Instruction HQMI 8610. lC, effective November 26, 1991. The purpose of these reports is to provide a documentation system that represents an internal discipline to establish critical discriminators selected in advance to measure mission accomplishment, provide a formal written assessment of mission accomplishment, and provide an accountability of technical achievement. Prelaunch reports are prepared and issued for each flight project just prior to launch. Following launch, updating (Post Launch) reports are issued to provide mission status and progress in meeting mission objectives. Primary distribution of these reports is intended for personnel having program/project management responsibilities

NASA\u27S Initial Flight Missions in the Small Explorer Program

The National Aeronautics and Space Administration (NASA) Office of Space Science and Applications has initiated a new component of the Explorer Program to provide research opportunities characterized by small, quick turn-around, and frequent space missions. The objective is to launch one to two payloads per year, depending on mission cost and availability of funds and launch vehicles. The first Small Explorer Announcement of Opportunity, released in May 1988, invited proposals in Astrophysics, Space Physics, and Upper Atmospheric Science disciplines. From the 51 proposals received, four missions were selected for flight. The initial flight missions described in this paper, in order of tentative launch date, are: the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX): the Submillimeter Wave Astronomy Satellite (SWAS); the Fast Auroral Snapshot Explorer (FAST); and the Total Ozone Mapping Spectrometer (TOMS). Future NASA plans for the Small Explorer program include issuing an Announcement of Opportunity every few years and selecting only the investigations that can be launched within a three year period. Some enhancement of launch vehicle capability and certain procedural changes for mission proposals are also anticipated

Nature's Grand Experiment: Linkage between magnetospheric convection and the radiation belts

The solar minimum of 2007–2010 was unusually deep and long lived. In the later stages of this period the electron fluxes in the radiation belts dropped to extremely low levels. The flux of relativistic electrons (>1 MeV) was significantly diminished and at times was below instrument thresholds both for spacecraft located in geostationary orbits and also those in low-Earth orbit. This period has been described as a natural “Grand Experiment” allowing us to test our understanding of basic radiation belt physics and in particular the acceleration mechanisms which lead to enhancements in outer belt relativistic electron fluxes. Here we test the hypothesis that processes which initiate repetitive substorm onsets drive magnetospheric convection, which in turn triggers enhancement in whistler mode chorus that accelerates radiation belt electrons to relativistic energies. Conversely, individual substorms would not be associated with radiation belt acceleration. Contrasting observations from multiple satellites of energetic and relativistic electrons with substorm event lists, as well as chorus measurements, show that the data are consistent with the hypothesis. We show that repetitive substorms are associated with enhancements in the flux of energetic and relativistic electrons and enhanced whistler mode wave intensities. The enhancement in chorus wave power starts slightly before the repetitive substorm epoch onset. During the 2009/2010 period the only relativistic electron flux enhancements that occurred were preceded by repeated substorm onsets, consistent with enhanced magnetospheric convection as a trigger

A Low-Cost Small Satellite Space Radar System

The advantages of space-based radar have been frequently noted for such applications as environmental monitoring, crop detection, soil-moisture determination, coastal ice measurement, and all-weather surveillance, to name just a few. The FLAPSTM ( Flat Parabolic Surface ) antenna technology developed by Malibu Research, enables the conception of a smallsatellite radar system. The design described in this paper is that of a lightweight surveillance satellite capable of being launched on a Pegasus booster. It is capable of detecting small ships and aircraft, such as may be required for drug-interdiction missions and other all-weather surveillance applications. The FLAPSTM antenna has many of the features of a phased array antenna at a small fraction of the cost or mass ordinarily associated with phased arrays. Moreover, a FLAPSTM antenna can be folded or rolled and stowed in a variety of ways to enhance the possibility of fitting within the limited volume available in a small ELV. We describe approaches to packaging and deployment of such an antenna, and the mating of these assemblies to a Fairchild-developed small satellite, and to the Pegasus air-launched vehicle. The satellite features a fiber-optic data bus, and the integration of an on-board processor with a solid-state recorder as has been provided to NASA for its recently launched Small Explorer satellite

GSFC Cutting Edge Avionics Technologies for Spacecraft

With the launch of NASA's first fiber optic bus on SAMPEX in 1992, GSFC has ushered in an era of new technology development and insertion into flight programs. Predating such programs the Lewis and Clark missions and the New Millenium Program, GSFC has spearheaded the drive to use cutting edge technologies on spacecraft for three reasons: to enable next generation Space and Earth Science, to shorten spacecraft development schedules, and to reduce the cost of NASA missions. The technologies developed have addressed three focus areas: standard interface components, high performance processing, and high-density packaging techniques enabling lower cost systems. To realize the benefits of standard interface components GSFC has developed and utilized radiation hardened/tolerant devices such as PCI target ASICs, Parallel Fiber Optic Data Bus terminals, MIL-STD-1773 and AS1773 transceivers, and Essential Services Node. High performance processing has been the focus of the Mongoose I and Mongoose V rad-hard 32-bit processor programs as well as the SMEX-Lite Computation Hub. High-density packaging techniques have resulted in 3-D stack DRAM packages and Chip-On-Board processes. Lower cost systems have been demonstrated by judiciously using all of our technology developments to enable "plug and play" scalable architectures. The paper will present a survey of development and insertion experiences for the above technologies, as well as future plans to enable more "better, faster, cheaper" spacecraft. Details of ongoing GSFC programs such as Ultra-Low Power electronics, Rad-Hard FPGAs, PCI master ASICs, and Next Generation Mongoose processors

Proposal for implementation of CCSDS standards for use with spacecraft engineering/housekeeping data

Many of today's low earth orbiting spacecraft are using the Consultative Committee for Space Data Systems (CCSDS) protocol for better optimization of down link RF bandwidth and onboard storage space. However, most of the associated housekeeping data has continued to be generated and down linked in a synchronous, Time Division Multiplexed (TDM) fashion. There are many economies that the CCSDS protocol will allow to better utilize the available bandwidth and storage space in order to optimize the housekeeping data for use in operational trending and analysis work. By only outputting what is currently important or of interest, finer resolution of critical items can be obtained. This can be accomplished by better utilizing the normally allocated housekeeping data down link and storage areas rather than taking space reserved for science