ALSA 2025 meeting

Due to the expansion of space operations, orbital debris creates increasing risks to governmental as well as business-related space activities. Conventional governance systems grounded in international treaties have not been able to effectively address these risks, while national mission approval systems are appearing as essential tools for space governance. This article responds to the following question: how does the Japanese mission approval system transform soft law into enforceable legal requirements, and how does it compare with the EU’s evolving regulatory approach to space debris governance?

Based on norm formation theory and legal pluralism, this article evaluates Japan’s legal framework, which incorporates administrative supervision to enforce debris mitigation standards. Through the use of international guidelines (such as those of COPUOS or IADC) to inform its mandatory national regulations, Japan operationalized soft law and made it an effective legal obligation. This differs from the EU’s evolving regulatory framework, where proposals for mandatory compliance are currently being considered, possibly moving away from voluntary self-regulation to more binding rules.

This article critically evaluates the Japanese regulatory framework, using empirical examples and case studies related to debris mitigation requirements (for example, autonomous deorbiting and post-mission disposal plans). The Japanese approach is contrasted with that of the EU, showing the difference both in theory and in practice, of operational behaviour and technical design choices in the two regions.

The paper places Japan’s approach within legal pluralism, analyzing how national systems lead to the development of legal obligations that interact with international frameworks. This discussion’s objective is to contribute to the establishment of more effective space debris governance frameworks globally.