The general trend towards increasing interest in the use of non-geostationary orbits (non-GSO) is gaining momentum. Global non-GSO systems are being launched in batches of satellites, and some already serve dozens of countries. The International Telecommunication Union (ITU) strives to keep pace with the fast development of technologies and ensure regulatory clarity in the use of radio frequencies and associated orbits, which are limited natural resources. An important step for their rational, efficient and economical use by satellite constellations was taken at the ITU World Radiocommunication Conference (WRC) in 2019. The application of new rules for bringing into use and phased deployment of non-GSO systems has already begun, and new gaps in post-deployment regulation have been identified. This paper describes possible ways to regulate the operation of satellite constellations in a post-deployment environment, as they were developed in preparation for the 2023 WRC.

This paper describes the role of the International Telecommunication Union (ITU) in the registration of satellite and other space systems with a focus on its response to the unprecedented surge of filings related to large satellite constellations. The paper will also discuss the upcoming World Radiocommunication Conference in late 2023 (WRC-23) which will amend the international Radio Regulations, a treaty addressing the use of radio spectrum and orbits, and ITU’s Master International Frequency Register. The paper will compare key elements of the ITU’s Master Register with the Register maintained by the United Nations (UN) Office of Outer Space Affairs pursuant to the Convention on Registration of Objects Launched into Outer Space. Finally, the paper will briefly explore opportunities for increased collaboration between these two UN organizations to address these shared challenges concerning registration of satellites.

The UN Register being a realization of the obligation of the UN Secretary-General to maintain that Register (Art. III of the Registration Convention) under information concerning each space object provided by States (Art. IV of the Registration Convention), helps all States and other actors of space activities to receive information about different space objects and its characteristics. Considering challenges from large and mega-constellations, including probability of space debris creation from their potential collisions, it is assumed that it is necessary to think about additional mechanisms, which the UN OOSA can use as a holder of the Register. On the one hand, it is suggested to encourage States to provide information not only under binding documents, but in accordance with soft law documents (like the GA Resolution 62/101), on the other hand, to provide more actual and comprehensive information to the Register.

The ITU has approved Resolution 216, which deals with the non-compliant use of radio frequencies for military purposes. Article 9 of the resolution allows states to appeal to the next WRC in case of disagreement with the RRB’s decision. However, until the response from the WRC, the Bureau's decision shall remain in abeyance. This raises questions about the rules that shall apply to the affected frequencies and the legal status of RRB’s decision. The consequences of non-compliance with ITU’s resolution may also affect the space regime, where the national non-appropriation principle is granitic. This brief paper aims to discuss the international legal consequences of non-compliance with ITU’s Resolution 216 and start an international discussion about the possibility of a new vision of the Outer Space legal status. It is essential to establish the ground rules for the new millennia space's endeavors, looking ahead instead of backward.

On 2 September 2019, the European Space Agency’s Aeolus Earth observation satellite was required to make an immediate axial shift — commonly known as a ‘delta-V’ manoeuvre — to avoid collision with SpaceX’s Starlink-44 satellite, which had lowered its orbital plane for system testing. Although SpaceX was notified of the imminent collision risk posed by changing Starlink-44’s orbit to the same altitude of Aeolus, SpaceX refused to change position, thereby requiring ESA to fire Aeolus’ thrusters to change orbit. On 3 December 2021 — two years after the Aeolus near-miss — the People’s Republic of China filed a note verbale to UNOOSA, detailing two instances of performing delta-v safety manoeuvres for its crewed platform the Tiangong space station to avoid collisions with satellites. Central to the issues facing both Aeolus and Tiangong is one party having to take the burden of performing a delta-v manoeuvre to change course. Spacecraft are equipped with a finite supply of propellant, thereby providing a limited amount of delta-v safety manoeuvres that can be performed before the propellant is exhausted. Where a propellent is exhausted, or near exhaustion, a spacecraft’s mission profile may be severely degraded, and it may have to be de-orbited. This paper will consider the liabilities of one party having to be compelled to frequently expend propellent to avoid collision due to a second party’s action and propose regulatory solutions to mitigate undue propellant expenditure.