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The historical development of space stations is presented through a series of various spacecraft configurations including: (1) Salut 6; (2) Skylab; (3) the Space Operations Center (SOC); (4) the Manned Science and Applications Space Platform; (5) Space Station Freedom; and (4) the Mir Space Station.
Routine satellite operations for the Earth Science Constellation (ESC) include collision risk assessment between members of the constellation and other orbiting space objects. Each day, close approach predictions are generated by a U.S. Department of Defense Joint Space Operations Center Orbital Safety Analyst using the high accuracy Space Object Catalog maintained by the Air Force's 1" Space Control Squadron. Prediction results and other ancillary data such as state vector information are sent to NASAJGoddard Space Flight Center's (GSFC's) Collision Risk Assessment analysis team for review. Collision analysis is performed and the GSFC team works with the ESC member missions to develop risk reduction strategies as necessary. This paper presents various close approach statistics for the ESC. The ESC missions have been affected by debris from the recent anti-satellite test which destroyed the Chinese Fengyun- 1 C satellite. The paper also presents the percentage of close approach events induced by the Fengyun-1C debris, and presents analysis results which predict the future effects on the ESC caused by this event. Specifically, the Fengyun-1C debris is propagated for twenty years using high-performance computing technology and close approach predictions are generated for the ESC. The percent increase in the total number of conjunction events is considered to be an estimate of the collision risk due to the Fengyun-1C break- UP.
The orbit maintenance problem is examined for two low-earth-orbiting space station concepts - the large, manned Space Operations Center (SOC) and the smaller, unmanned Science and Applications Space Platform (SASP). Atmospheric drag forces are calculated, and circular orbit altitudes are selected to assure a 90 day decay period in the event of catastrophic propulsion system failure. Several thrusting strategies for orbit maintenance are discussed. Various chemical and electric propulsion systems for orbit maintenance are compared on the basis of propellant resupply requirements, power requirements, Shuttle launch costs, and technology readiness.
The role of the Space Operations Center (SOC) as it effects the missions of the space shuttle was analyzed. Graphic representation of space shuttle docking procedures with attention to the docking module was presented. Other topics included extravehicular activity options, space station evaluation, space logistics of the SOC, equipment interfacing, and SOC buildup scenarios.
NASA is committed to safety of flight for all of its operational assets Performed by CARA at NASA GSFC for robotic satellites Focus of this briefing Performed by TOPO at NASA JSC for human spaceflight he Conjunction Assessment Risk Analysis (CARA) was stood up to offer this service to all NASA robotic satellites Currently provides service to 70 operational satellites NASA unmanned operational assets Other USG assets (USGS, USAF, NOAA) International partner assets Conjunction Assessment (CA) is the process of identifying close approaches between two orbiting objects; sometimes called conjunction screening The Joint Space Operations Center (JSpOC) a USAF unit at Vandenberg AFB, maintains the high accuracy catalog of space objects, screens CARA-supported assets against the catalog, performs OD tasking, and generates close approach data.
This paper is concerned with the presentation of mission-independent software systems that provide a common software platform to ground data systems for mission operations. The objectives of such common software platforms are to reduce the cost of the development of mission-dedicated software systems and to increase the level of reliability of the ground data systems for mission operations. In accordance with this objective, the Multi-Satellite Support System (MSSS) was developed at the European Space Operations Center (ESOC). Between 1975 and 1992, the MSSS provided support to 16 European Space Agency (ESA) missions, among them very demanding science missions such as GEOS, EXOSAT, and Giotto. The successful support of these missions proved the validity of the MSSS concept with its extended mission-independent platform. This paper describes the MSSS concept and focuses on the wide use of MSSS as a flight control system for geosynchronous telecommunications satellites. Reference is made to more than 15 telecommunications missions that are operated from Western Europe using flight control systems with an underlying MSSS concept, demonstrating the benefits of a commonly used software platform. Finally, the paper outlines the design of the new generation of flight control systems, which is being developed at ESOC for this decade, following a period of more than 15 years of MSSS support.
Although it is possible to design manned missions to Mars that do not involve prior lunar missions, a strategy that includes development of a lunar base before or concurrent with the Mars program offers potential benefits from space infrastructure development, space operations experience, and utilization of lunar materials for propulsion. Common utilization of infrastructure elements (e.g., Orbital Transfer Vehicles, Space Operation Center modules) is emphasized in this approach. Mass flows through a low Earth orbit Space Station change in quantity and in proportion of propellant to hardware as the infrastructure develops.
In order to demonstrate the possibilities for scientific networking and data transfer, a first temporary satellite network link was installed between Czecholovakia and the European space operations center in Darmstadt, during the meeting of the inter-agency consultative group for space science in Prague. Several experiments to show interactive nature of the facility and the capability of the system were carried out, and it was proven that, despite the temporary nature of the installation, the planned demonstrations could be conducted in real time. Demonstrations included electronic mail message, orbit prediction and solar X-ray data. The results of the experiment provided insight into possibilities of data exchange.
Turnaround requirements for the manned orbital transfer vehicle (MOTV) baseline and alternate concepts with and without a space operations center (SOC) are defined. Manned orbital transfer vehicle maintenance, refurbishment, resupply, and refueling are considered as well as the most effective combination of ground based and space based turnaround activities. Ground and flight operations requirements for abort are identified as well as low cost approaches to space and ground operations through maintenance and missions sensitivity studies. The recommended turnaround mix shows that space basing MOTV at SOC with periodic return to ground for overhaul results in minimum recurring costs. A pressurized hangar at SOC reduces labor costs by approximately 50%.
This paper presents selected features of a human factors oriented plan for a Space Station Freedom (SSF) ground Discipline Operations Center (DOC) that is integrated with other work areas used by multidisciplinary life scientists. This combined facility is referred to as an integrated DOC or IDOC. This plan is based upon the assumption that there will be a constantly changing array of specialized equipment and procedures used by life sciences principal investigators (PI) on the ground which must be linked to SSF through various DOC systems. Other sites will also be able to communicate with SSF (Anon., 1992). It is also assumed that cost reduction will be a major design consideration and that one integrated structure will be less expensive to build and operate than two separate ones. Since both the DOC personnel and PIs will need to communicate with the flight crew aboard SSF, the general interconnect architecture of the PIs' communication linkage is considered here. Key human factor design elements of this plan include: a candidate facility layout which accommodates three (3), multipurpose, rapidly reconfigurable work areas (suites) and consequent user traffic flow considerations, a multimedia telecommunications support capability, functional (human) traffic flow, optimized internal illumination and acoustics requirements, selected volumetric and safety requirements, and other architectural design parameters.
Extended manned space missions which include interplanetary missions require regenerative life support systems. Manned mission life support considerations are placed in perspective and previous manned space life support system technology, activities and accomplishments in current supporting research and technology (SR&T) programs are reviewed. The life support subsystem/system technologies required for an enhanced duration orbiter (EDO) and a space operations center (SOC), regenerative life support functions and technology required for manned interplanetary flight vehicles, and future development requirements are outlined. The Space Shuttle Orbiters (space transportation system) is space cabin atmosphere is maintained at Earth ambient pressure of 14.7 psia (20% O2 and 80% N2). The early Shuttle flights will be seven-day flights, and the life support system flight hardware will still utilize expendables.
STI is for a fact sheet on the Space Object Query Tool being created by the MDC. When planning launches, NASA must first factor in the tens of thousands of objects already in orbit around the Earth. The number of human-made objects, including nonfunctional spacecraft, abandoned launch vehicle stages, mission-related debris and fragmentation debris orbiting Earth has grown steadily since Sputnik 1 was launched in 1957. Currently, the U.S. Department of Defenses Joint Space Operations Center, or JSpOC, tracks over 15,000 distinct objects and provides data for more than 40,000 objects via its Space-Track program, found at space-track.org.
An advanced network interface was designed and implemented by a team from the Jet Propulsion Lab with support from the European Space Operations Center. This poster shows the requirements for the interface, the design, the topology, the testing and lessons learned from the whole implementation.
A detailed discussion of the use of channel coding for error correction, privacy/secrecy, channel separation, and synchronization is presented. Channel coding, in one form or another, is an established and common element in data systems. No analysis and design of a major new system would fail to consider ways in which channel coding could make the system more effective. The presence of channel coding on TDRS, Shuttle, the Advanced Communication Technology Satellite Program system, the JSC-proposed Space Operations Center, and the proposed 30/20 GHz Satellite Communication System strongly support the requirement for the utilization of coding for the communications channel. The designers of the space station data system have to consider the use of channel coding.
The Applied Meteorology Unit (AMU) evaluated the Regional Atmospheric Modeling System (RAMS) contained within the Eastern Range Dispersion Assessment System (ERDAS). ERDAS provides emergency response guidance for Cape Canaveral Air Force Station and Kennedy Space Center operations in the event of an accidental hazardous material release or aborted vehicle launch. The RAMS prognostic data are available to ERDAS for display and are used to initialize the 45th Space Wing/Range Safety dispersion model. Thus, the accuracy of the dispersion predictions is dependent upon the accuracy of RAMS forecasts. The RAMS evaluation consisted of an objective and subjective component for the 1999 and 2000 Florida warm seasons, and the 1999-2000 cool season. In the objective evaluation, the AMU generated model error statistics at surface and upper-level observational sites, compared RAMS errors to a coarser RAMS grid configuration, and benchmarked RAMS against the nationally-used Eta model. In the subjective evaluation, the AMU compared forecast cold fronts, low-level temperature inversions, and precipitation to observations during the 1999-2000 cool season, verified the development of the RAMS forecast east coast sea breeze during both warm seasons, and examined the RAMS daily thunderstorm initiation and precipitation patterns during the 2000 warm season. This report summarizes the objective and subjective verification for all three seasons.
The German Space Operations Center (GSOC) Spacelab D2 mission system is a forerunner of the GSOC system which will accept 'virtual channel' transfer frame data directly from the NASA Consumer Data and Operations System (and/or the equivalent European and Japanese ground data handling systems). This experience with the Consultative Committee for Space Data Systems (CCSDS) will prepare GSOC to implement an effective and efficient system for control of payloads and for the handling of CCSDS-format data well into the 21st century.
Satellite conjunction assessment is perhaps the fastest growing area in space situational awareness and protection with military, civil and commercial satellite owner-operators embracing more and more sophisticated processes to avoid the avoidable - namely collisions between high value space assets and orbital debris. NASA and Centre National d'Etudes Spatiales (CNES) have collaborated to offer an introductory short course on all the major aspects of the conjunctions assessment problem. This half-day course will cover satellite conjunction dynamics and theory. Joint Space Operations Center (JsPOC) conjunction data products, major risk assessment parameters and plots, conjunction remediation decision support, and present and future challenges. This briefing represents the NASA portion of the course.
The NASA Robotic Conjunction Assessment Risk Analysis (CARA) team sends ephemeris data to the Joint Space Operations Center (JSpOC) for conjunction assessment screening against the JSpOC high accuracy catalog and then assesses risk posed to protected assets from predicted close approaches. Since most spacecraft supported by the CARA team are located in LEO orbits, atmospheric drag is the primary source of state estimate uncertainty. Drag magnitude and uncertainty is directly governed by atmospheric density and thus space weather. At present the actual effect of space weather on atmospheric density cannot be accurately predicted because most atmospheric density models are empirical in nature, which do not perform well in prediction. The Jacchia-Bowman-HASDM 2009 (JBH09) atmospheric density model used at the JSpOC employs a solar storm active compensation feature that predicts storm sizes and arrival times and thus the resulting neutral density alterations. With this feature, estimation errors can occur in either direction (i.e., over- or under-estimation of density and thus drag). Although the exact effect of a solar storm on atmospheric drag cannot be determined, one can explore the effects of JBH09 model error on conjuncting objects' trajectories to determine if a conjunction is likely to become riskier, less risky, or pass unaffected. The CARA team has constructed a Space Weather Trade-Space tool that systematically alters the drag situation for the conjuncting objects and recalculates the probability of collision for each case to determine the range of possible effects on the collision risk. In addition to a review of the theory and the particulars of the tool, the different types of observed output will be explained, along with statistics of their frequency.