Journal of Space Safety Engineering最新文献

Within the European Space Agency's (ESA) Space Weather Service Network, the development of performance indicators for the Global Navigation Satellite System (GNSS) has been identified as essential to meet the growing needs of end users for Space Weather information in the field of navigation. This requires a targeted analysis of Space Weather-related disturbances of technical systems and services in the field of satellite-based navigation, considering the growing requirements of all the different users in this domain. The goal of the Space Weather Impact on GNSS Performance: Application Development (SWIGPAD) project is to develop GNSS performance indicators (GPI) based on Space Weather data provided by European research institutes through the ESA Space Weather Service Portal (available at https://swe.ssa.esa.int) with the aim to fulfill representative use cases derived from dedicated meeting with industry and government experts. The application that serves the GPI will provide the user with information about current and expected effects of Space Weather on positioning at their respective location. Additionally, end users in the various GNSS application domains shall be assisted with an overall numerical and graphical estimate of the positioning uncertainty resulting from ionospheric conditions and its evolution over time. The intent of this article is to present the results of the project and the capabilities of the GPI application.

The use of X-rays in CT-scan imaging in the treatment stages of patients is inevitable, but there is still a lack of suitable coverings in order to eliminate the risk of this radiation coming into contact with humans and its dangerous consequences. In this study, at first, bismuth and zirconia nanoparticles were synthesized using olive tree leaves. The structure of the synthesized nanoparticles was confirmed by scanning electron microscopy and X-ray diffraction. Then seven composites were prepared using an twin screw extruder machine. The output sheets had a thickness of 1 mm. Structural properties such as surface morphology, density of prepared composites, mechanical properties of Young's modulus, thermal gravimetric analysis and retention of loaded particles after three times washing were investigated. The sheets were cut into 10 cm² dimensions and their X-ray attenuation ability was investigated. The results indicate that all sheets filled with bismuth and zirconia particles and nanoparticles have more X-ray attenuation than pure polymer. Among the prepared sheets, composites LDPE (77%) + Bi₂O₃ (20%) +MWCNTs (3%), LDPE (80%) + Bi₂O₃ (20%), and LDPE (77%) + Bi₂O₃ (10%) + ZrO₂ (10%) + MWCNTs (3%) in order showed the highest X-ray attenuation effect and are competitive with standard samples. Carbon nanotubes showed a synergistic effect in X-ray attenuation.

Over the past 30 years, an extensive knowledge-base in the construction and utilization of risk matrices to score and rank risks has been accumulated. Still, within the domain of the continuous risk management (CRM) process, key issues associated with risk matrices have produced divergent schools of thought: a utilitarian focus among practitioners, and a more theoretical, and sometimes abstract, focus among the academic community. This research will examine CRM practices in human space flight at the National Aeronautics and Space Administration (NASA) and the U.S. Department of Defense (DoD), including many of their aerospace contractors, to assess the key factors in the construction and use of risk matrices. The intent here is to begin to merge the knowledge between these communities in an effort to support a research agenda to improve the construction and use of risk matrices going forward.

The rapid growth of the global space industry opens the door to an increasing volume and variety of space activities at the same time that companies are increasingly recognizing the value of environmentally responsible business practices. The environmental impacts of space activities are particularly challenging to understand and address given their complexity and distribution across different domains and industries. Multiple key areas still suffer from a lack of research, leaving critical knowledge gaps. Environmental life cycle assessments (E-LCAs) are one tool that can be applied to understand the space sector's cradle-to-grave impacts across space and terrestrial environments. Specifically, an E-LCA can identify circular economy opportunities to reduce waste and pollution by quantifying the environmental impacts of space missions or systems over their entire life cycle.¹

This paper provides an overview of environmental and sustainability trends and offers options for the U.S. government, and Department of Defense (DOD) in particular, to consider and adopt E-LCAs in space acquisitions. As both DOD and civilian spacefaring agencies seek reduced environmental footprints, E-LCAs can motivate the space industry to improve designs, practices, and realize operational and economic efficiencies.

Additionally, the U.S. government is in a strong position, as a large and influential buyer of space systems, to support the harmonization of E-LCA methodologies and frameworks with international partners. Such efforts could catalyze a sustainable space industry while building transparency and trust for all stakeholders.

Consequent to Anti-Satellite tests by China (in 2007) and India (in 2019), coupled with the potential militarization of space and advanced developments in space technology; strategic balance in South Asia is being affected by the new space race after the Cold War era. Currently, South Asia is in a trilemma due to China, India, and Pakistan's evolving space environment and varying security dynamics. In particular, the Indian quest for regional hegemony to counter China, to become “The Great Power” has further complicated the situation. In this context, this study presents a comprehensive overview of global outer space exploration, examines India's evolution in the outer space domain, analyzes the historic perspective of Indian quest for power and influence on the regional and global community as well as evaluates India's collaboration in space projects and space governance. The innovative space technologies are likely to have significant implications for strategic stability and space power competition in South Asia. Analyzing the likely impact of India's potential hegemonic design and quest for power and influence in the outer space domain; this study explores the technological asymmetries and the Indian quest for power likely to create strategic instability which may ultimately lead to unnecessary space race through investments in space technology and weaponization of space. Moreover, it would create a particular space block threatening the interests of the region and the global peaceful use of space. This study also presents comprehensive implications and associated recommendations for stability in the region.

As the human space flight industry continues to expand at a rapid pace, the inherent risks of space travel remain unchanged. An emerging property in this new era is the increased use of performance-based requirements to minimize risks in lieu of heritage prescriptive requirements. One element of this new approach is a movement toward reliability and risk calculations in place of prescriptive failure tolerance and dissimilar redundancy requirements.

This paper examines this new trend through the lens of historical lessons learned that drove failure tolerance and dissimilar redundancy in past human spaceflight programs. An important historical case to examine is the use of dissimilar redundancy in the design for the Apollo missions. There are two standout examples in the Apollo mission architecture: the Lunar Module (LM) lifeboat contingency and the abort scenarios during LM Descent and Landing (DL). Through these two examples we can understand how dissimilar redundancy was achieved to mitigate the risk of loss of crew, and the penalties that came along with these design decisions. We then compare these examples with new ideas about redundancy and established practices in other industries, like commercial aviation.

Finally, we evaluate how these trades made in aeronautics can inform the next generation of designs in astronautics and how future programs can evaluate the added complexity and mass impacts of redundancy with the safety advantages that redundancy brings to modern spaceflight designs.

Over the past decades, industries and governments have progressively been relying upon space data-centric and data-dependant systems. This led to the emergence of malicious activities, also known as cyber-threats, targeting such systems. To counter these threats, new technologies such as Artificial Intelligence (AI) have been implemented and deployed. Today, AI is highly capable of delivering fast, precise, and reliable command-and-control decision-making, as well as providing reliable vulnerability analysis using well-proven cutting-edge techniques, at least when applied to terrestrial applications. In fact, this might not yet be the case when used for space applications. AI can also play a transformative and important role in the future of space cybersecurity, and it poses questions on what to expect in the near-term future.

Challenges and opportunities deriving from the adoption of AI-based solutions to achieve cybersecurity and later cyber defence objectives in both civil and military operations require rethinking of a new framework and new ethical requirements. In fact, most of these technologies are not designed to be used or to overcome challenges in space. Because of the highly contested and congested environment, as well as the highly interdisciplinary nature of threats to AI and Machine Learning (ML) technologies, including cybersecurity issues, a solid and open understanding of the technology itself is required, as well as an understanding of its multidimensional uses and approaches. This includes the definition of legal and technical frameworks, ethical dimensions and other concerns such as mission safety, national security, and technology development for future uses.

The continuous endeavours to create a framework and regulate interdependent uses of combined technologies such as AI and cybersecurity to counter “new” threats require the investigation and development of “living concepts” to determine in advance the vulnerabilities of networks and AI.

This paper defines a cybersecurity risk and vulnerability taxonomy to enable the future application of AI in the space security field. Moreover, it assesses to what extent a network digital twins’ simulation can still protect networks against relentless cyber-attacks in space against users and ground segments. Both concepts are applied to the case study of Earth Observation (EO) operations, which allows for conclusions to be drawn based on the business impact (reputational, environmental, and social) of a cyber malicious activity. Since AI technologies are developing on a daily basis, a regulatory framework is proposed using ethical and technical approaches for this technology and its use in space.

The aerospace community and industry have recently shown increasing interest towards the use of Artificial Intelligence (AI) for space applications, partially driven by the recent development of the NewSpace economy. AI has already come into extensive use in spacecraft operations, for example to support efficient operations of satellite constellations and system health management. However, since most critical infrastructures rely on space systems, the use of new technologies, such as AI algorithms or increased system autonomy on-board, introduces further vulnerabilities on the system level. As a matter of fact, AI cyber security is becoming an important aspect to ensure space safety and operational security. Apart from identifying new vulnerabilities that AI systems may introduce to space assets, this paper seeks for safety guidelines and technical standardisations developed for terrestrial applications that can be applicable to AI systems in space. Existing policy guidance for cybersecurity and AI, especially for the European context, is discussed. To promote the safe use of AI technologies in space this work underlines the urgency for policymakers, governance, and technical institutions to initiate or further support the development of a suitable framework to address the new cyber-vulnerabilities introduced by AI technologies when applied to space systems. The paper suggests a regulatory approach based on technical standardisation in the field of AI, which is built upon a multidisciplinary research of AI applications in non-space sectors where the level of autonomy is more advanced.

In May 2021, the Supplementary Requirements for a License to Operate a Spacecraft Performing On-Orbit Servicing were established and published in Japan. The Supplementary Requirements were made as the Rules for a person who intends to carry out on-orbit servicing mission including active debris removal. The Rules were to be reflected in the licensing schemes within the already existent framework of the Space Activities Act, which provides the requirements to obtain a license to control a spacecraft in Japan. Consisting of legal, technical, and organizational requirements, the Rules provide a framework to carry out on-orbit servicing mission based on the agreements and consents among the stakeholders. The Rules address the legal and technical risks derived especially from the rendezvous and proximity operations phases in the on-orbit servicing mission profile. This framework implicates the principles of safe and transparent operations as the norms for the on-orbit servicing missions, and its approach demonstrates adaptive governance in the sense that the Rules were deliberated among multi-sector stakeholders, they are expected to be introduced and extended internationally, and they are flexible to technology development. This paper explains the Rules from the points of view of risk-based approach and adaptive governance and aims to gain the perspectives on the possible approaches to establish the international rules and norms for emerging space activities.

Within the next decade it is likely that the space tourism industry will grow dramatically and the number of humans travelling into, and beyond, the stratosphere via commercial entities such as World View and Space Perspective will increase. Current space tourism ventures focus on long duration very high altitude balloon flights; also known as ‘near space’ flights, sub-orbital flights and visits to Low Earth Orbit (LEO). In the next few decades space tourism is ultimately likely to become routine. During these new commercial ventures the effects of cosmic radiation exposure, especially during sudden changes in space weather, such as ground level enhancement (GLE) events, could have significant health implications for crew and passengers. The risks from these rapid changes in space weather and potential radiation exposure during flights is not currently fully understood or even acknowledged. Legislation and regulation for such enterprises is also in its infancy with little or no guidance for commercial entities or potential passengers. Initial work at the University of Surrey has focused on very high altitude ‘near space’ balloon flights. World-wide launch locations for flights have been modelled using MAIRE and CARI-7 computer programs. Flight routes have been monitored, for current commercial and higher flight levels, using the Smart Atmospheric Ionizing Radiation (SAIRA) detector. The modelled flight profiles have been compared with detector data, up to a maximum flight altitude of 30 km (100,000 ft), with varying space weather conditions, from norms to extreme events, to assess the radiation risk presented by potential exposure.

Plain Language Summary: An assessment of the risks and potential radiation exposure from flying to ‘near space’ within newly designed observation balloons at very high altitude in the upper atmosphere above the Earth. Looking at the impact of radiation from the sun and sources outside the solar system, and critically when these conditions vary which could result in high levels of exposure.