  This paper explores the transformative potential of digital twin (DT)
technology in the context of non-terrestrial networks (NTNs). NTNs,
encompassing both airborne and space-borne elements, present unique challenges
in network control, management, and optimization. DT is a novel approach to
design and manage complicated cyber-physical systems with a high degree of
automation, intelligence, and resilience. The adoption of DTs within NTNs
offers a dynamic and detailed virtual representation of the entire ecosystem,
enabling real-time monitoring, simulations, and data-driven decision-making.
This paper delves into the envisioned integration of DTs in NTNs, discussing
the technical challenges and highlighting key enabling technologies. Emphasis
is placed on technologies such as Internet of things (IoT), artificial
intelligence (AI), space-based cloud computing, quantum computing, and others,
providing a comprehensive overview of their potentials in empowering DT
development for NTNs. In closing, we present a case study involving the
implementation of a data-driven DT model to facilitate dynamic and
service-oriented network slicing within an open radio access network (O-RAN)
architecture for NTNs. This work contributes to shaping the future of network
control and management in the dynamic and evolving landscape of non-terrestrial
communication systems.
