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Environmental concerns have increasingly led governments to implement legislation which ensures that mining companies plan for the depletion of non-renewable resources and the eventual closure of mining operations. Focusing on South Africa, this paper will make proposals for how to plan for the reorientation of the lives of those affected by mine closure or downscaling.

The next generation of NOAA's Geostationary Operational Environmental Satellite system, Series R (GOES-R) provides continuity of the GOES mission and improvement of its remotely-sensed environmental data. The GOES-R system consists of the Space and Ground Segments. The Space Segment consists of spacecraft bus, its remote-sensing instruments, and communications payloads; while the Ground Segment consists of all Earth-based functions, provides satellite operations and instrument product generation and distribution. This paper presents an overview of the GOES-R Ground Segment (GS) architecture as it continues to evolve consistent with the GOES-R Ground Segment Project (GSP) approved requirements documents. The GOES-R Ground Segment operates from three sites. The first is the NOAA Satellite Operations Facility (NSOF) in Suitland, MD which houses the primary Mission Management (MM), and selected Enterprise Management (EM), Product Generation (PG), and Product Distribution (PD) functions. The Wallops Command and Data Acquisition Station (WCDAS), located in Wallops, VA, provides the primary space communications services, EM and MM functions, and selected PG and PD functions. The third site is a geographically diverse remote backup facility (RBU) located at Fairmont, WV. The architecture has been developed to allow integrated operation within a geographically distributed framework. Because of the unique configuration of the Mission Management Element, the Wallops Command and Data Acquisition Site will have the ability to assume control of satellite operations in the event of an emergency - when authorized by the primary NSOF controllers. This concept allows the Enterprise Management element to have available a wide range of capabilities governed by operations policy rather than the need for system upgrades. This concept also provides flexibility for addition and deletion of modules for major functions. The use of Service Based Architecture concepts within the Product Generation element (PG) provides service interaction capabilities for product generation with only a fraction of the necessary overhead.

Titanium containing compounds are valuable materials for addition to the blast furnace to extend operational compaigns. However, the addition of these materials via the sinter plant has been known to create problems. This study investigates the effect of adding a titanomagnetite to two sintering ore blends, containing 10 and 20% pisolitic limonite respectively. The addition of up to 2% titanomagnetite did not affect the sintering parameters or sinter quality. Increasing the titanomagnetite levels to greater than 3% also had no significant influence on sintering but a signficant deterioration in sinter RDI was recorded. Results also showed that the deterioration in RDI was greater for the blend containing more pisolitic limonite.SEM studies carried out on the product sinters found most of the titanium in the glass phase. The mechanical properties of the glass was characterised using indentation fracture mechanics. Although some difficult was experienced, due to the small and disperse nature of the glass, addition studies using artifically manufactured glass indicated that the fracture toughness of the glass decreased with increasing titanium levels. It is postulated that because glass in the weakest phase in sinter and is widely dispersed any reduction in its fracture toughness will increase the vulnerability of the sinter to crack propagation, thereby increasing sinter RDI. It is also postulated that increasing the pisolitic level increased melt formation and the dispersion of the glass phase, resulting in a further deterioration in sinter RDI.

The significant increase in the number of proposed science and military distributed spacecraft mission concepts has been built on the promise of expanded capability, improved robustness, and graceful degradation of assets. The challenge to realizing this promise lies in managing the complexity of any coordination required among the spacecraft and the ability to feasibly implement the systems. In addition, cost drivers, often related to launch services, commonly drive distributed spacecraft system designers to consider small, physically limited satellites (e.g., microsats or nanosats) as the assets in the space segment of the system. To address the challenge of complexity for coordinating multiple spacecraft in a practical manner, the described research details developments in autonomous command and control that leverage formal methods of discrete event systems. This approach is particularly applicable to small satellites because it can be developed at multiple levels of

Formation Flying is revolutionizing Earth and Space science and the way the space community conducts science missions. This technological transformation provides new, innovative techniques in spacecraft guidance, navigation, and control, and how the science community gathers and shares information between space vehicles and the ground. These technologies will also expedite the human exploration of space. Once fully matured, this technology will result in swarms of space vehicles flying as virtual platforms or distributed space systems and sensor webs which gather significantly more and better science data than is possible today. Formation flying will be enabled through the development and deployment of automated spaceborne guidance, navigation, and control (GN&C) systems integrated with intrasatellite communications infrastructure. Innovative spacecraft autonomy techniques, such as differential Global Positioning System (GPS) technology, optical, and vision-based navigation and celestial navigation allow autonomous navigation while other technologies provide for the autonomous control methods to maintain and optimize these formations. This paper provides a vision of the future of space exploration in the context of GN&C technology, and an overview of the current status of NASA technology development and its partnerships with the Department of Defense (DoD), Industry, and University to bring formation flying technology to the forefront as quickly as possible. We address the impediments that need to be overcome to achieve the distributive spacecraft vision and NASA GSFC's approach to transfer this technology to space. We will also describe some of the formation flying testbeds, such as the on-orbit Air Force Research Laboratory (AFRL) University Nanosats, and Orion test beds and ground based GSFC Formation Flying Test Bed, which are being developed to demonstrate and validate innovative position sensing and formation control technologies.

Spacecraft missions are seeking alternative and innovative ways to rapidly reduce mission costs. Automating maneuver planning processes plays a significant role in achieving that goal. FreeFlyer™ and AutoCon™, developed by AI Solutions, are tools being used by current National Aeronautics and Space Administration (NASA) missions to efficiently perform flight dynamics processes, while reducing costs. The Earth Observing System (EOS) AM-l spacecraft and Landsat-7 spacecraft are using FreeFlyer™, while the Earth Orbiter 1 (EO-1) is using AutoCon™, a precursor to FreeFlyer™, for orbital analysis, maneuver planning and product generation. EOS AM-l will perform frequent ground track maintenance maneuvers to maintain orbital constraints. Additional orbital and operational constraints will be taken into account while planning these maneuvers. FreeFlyer™ uses a robust natural scripting language to model mission environments while performing maneuver planning Advanced targeting capabilities and fuzzy logic are incorporated into FreeFlyer™ to resolve and achieve complex mission constraints. EO-1 will be using AutoCon1™ both on ground and on board. A unique targeting algorithm incorporated into AutoCon M, developed by Goddard Space Flight Center (GSFC), will plan maneuvers for formation flying with Landsat7. A sequential progression towards autonomous maneuver planning, including formation flying using AutoCon™, will be demonstrated with the EO-1 mission.

This paper describes the formation of a partnership between two competing technologies with very different approaches to the problem of enhanced formation flying (EFF) on the New Millennium Program (NMP) Earth Orbiter (EO)-l mission. This includes a brief description of the two approaches that were independently proposed by the Goddard Space Flight Center (GSFC)/Stanford University and JPL teams. The actual mission combines these two approaches within a single autonomous control architecture called AutoCon™. The software is designed so that a control mode switch can be set by the ground flight operations team to invoke either EFF algorithm. The advantage of this approach is that both EFF technologies can be incorporated onboard EO-1 within the AutoCon™ framework. In addition, the details of each proposed algorithm need not be divulged provided that the algorithms conform to the specifications of AutoCon™. Forming a partnership between two competing technologies represents a significant programmatic challenge. This paper discusses the programmatic issues and several of the technologies that have been developed to perform the EFF mission. In the process, several recommendations are provided that should streamline similar partnerships on future NMP missions.