# New Space Engineering Design: Characterization of Key Drivers
## 3 Results and Discussion
### General Discussion of New Space Design Drivers and Enablers
#### 3.1.3 Category C: Sustainability and Technological Independence
Further sustainability concerns regard the Earth's upper atmosphere as follows: changes in the stratospheric composition, ozone layer depletion, potential health risks, as well as interference with ground-based astronomy, all associated with particles released during launches, particularly from solid rocket boosters, and reentry burn-ups [62]. Alongside EOL considerations, promoting a more sustainable approach to the development of space products and processes requires evaluating the entire life cycle and supply chain of the system. To assess the environmental footprint of space projects, a design framework can incorporate metrics such as toxicity, climate change impact, and resource utilization [63]. On the regulatory side, concrete actions have been taken, including restrictions on the use of certain polluting and unsafe substances, with further limitations expected soon [64]. As in other industries, specific tools such as life cycle assessment (LCA) are now being applied to evaluate environmental impacts from the initial stages of space product development, in line with methodological approaches such as eco-design and Design for Environment [65]. Designers can anticipate the effects of alternative design solutions and eliminate environmentally critical options, but not without challenges related to the specificity of the space environment. In particular, EOL operations, the unique materials and manufacturing processes involved, and the limited availability of relevant data pose significant barriers to conducting meaningful LCAs in the space sector. Conventional environmental databases are limited in characterizing space-related activities, and studies are investigating critical aspects such as the environmental effects of complex particulates released during spacecraft atmospheric reentry [29; 66]. Nonetheless, eco-design strategies can be cautiously adapted to the space sector, for example, by aligning with ISO 14040 and ISO 14044, which are international standards for LCA [67; 68]. Dedicated guidelines and databases developed by institutions like ESA are being integrated with typical LCA tools such as SimaPro [69] and openLCA [70]. While methodological and data limitations exist, recent efforts are beginning to address these gaps. Following ESA guidelines, one example proposes a sustainable-oriented multi-criteria decision framework for comparing in-space propulsion systems across different mission scenarios, incorporating performance, cost, reliability, and environmental impact [71; 72]. Another study adopts the ReCiPe 2016 midpoint (H) method under ISO 14044 to evaluate the environmental impact of alternative manufacturing techniques for space propellant tanks [73]. A further conceptual study explores a broader eco-design approach, mapping R10 circularity strategies across space product development phases [74]. While these cases illustrate promising directions, the systematic integration of sustainability metrics into space engineering practices remains an emerging field of research. This sustainability-oriented perspective influences decisions at all design levels, from system architecture to component selection, across various areas, including propulsion, thermal, and power management systems, as well as manufacturing processes. With a long-term vision, strategic space system design may be based on the intersection of conventional Earth-based solutions, emerging innovation, and the availability of resources directly accessible in space. The near future is expected to see the realization of the in situ production and utilization of critical materials already present in the space environment. Propellants, structural components, and, above all, water are among the key resources that could be processed or produced on-site [24].