The emergence of the construction and operation of a small satellite constellation in Low Earth orbit (LEO) to beam high-speed Internet to all parts of the world is a relatively new development in the use of outer space. States, international intergovernmental organizations, and private companies plan to deploy small satellites into Earth’s orbit because this effort is inexpensive and expandable, especially in the area of commercial activities. This movement will provide an essential tool to achieve sustainable development goals, especially for developing countries. However, it could also bring legal challenges because there is now a lack of binding regulations regarding the increasing risks of orbital collision, the proliferation of space debris, the satellite network service, and the rational, efficient, and economical use of a radio frequency allocation and the harmful interference caused by small satellite constellations in LEO. These issues could have an impact on the long-term sustainability of space activities.

I. Introduction
II. The Legal Challenge of the PotentialSatellite Collision
    A. Guideline for the Long-term Sustainability of Outer Space Activities
    B. Draft International Code of Conduct for Outer Space Activities.
III. Space Debris
    A. The European Space Debris Safety and Mitigation Standard
    B. The Inter-Agency Space Debris Coordination Committee’s SpaceDebris Mitigation Guideline
    C. The UNCOPUOS Space Debris Mitigation Guideline
IV. The Satellite Network Service
V. Radio Frequency Allocation andHarmful Interference
    A. Radio Frequency Allocation
    B. Harmful Interference
VI. Conclusion

• Chandaphan Suwijak(Ph.D. candidate at Beijing Institute of Technology. LL.B. (Mae Fah Luang U.- Thailand), LL.M. (Chulalongkorn))
• Shouping Li(Professor of International Law; Dean of Law School; Director of Space Institute at Beijing Institute of Technology. Ph.D. (Wuhan), / Post-Doc (Fudan))