Author: CislunarSpace
Website: https://cislunarspace.cn

National University of Defense Technology

The National University of Defense Technology (NUDT, 国防科技大学) traces its origins to the People's Liberation Army Military Engineering Institute (哈军工), established in Harbin in 1953 under the leadership of General Chen Geng. It was the PRC's first higher military engineering institution. In 1970, the main body relocated to Changsha and was renamed Changsha Institute of Technology. In 1978, it was reorganized as the PLA National University of Defense Technology. In 2017, NUDT was rebuilt under the Central Military Commission by merging several military academies and research institutes.

NUDT has received sustained attention from the CPC Central Committee and the Central Military Commission. It was among the 20 national key universities designated in 1959, one of the first institutions authorized to grant master's and doctoral degrees, and the only military institution in both "Project 985" and the first round of "Double First-Class" construction. The university's academic system covers six discipline categories — science, engineering, military science, management, law, and literature — with 61 undergraduate programs, 26 master's first-discipline authorization points, and 23 doctoral first-discipline authorization points. Five disciplines — Information and Communication Engineering, Computer Science and Technology, Aeronautical and Astronautical Science and Technology, Software Engineering, and Management Science and Engineering — are on the national "Double First-Class" list.

NUDT's research output relevant to cislunar space includes work on space security strategy, low-energy transfer orbit design, and orbital parameter characterization for cislunar libration points.

Yang Leping

Professor at NUDT, space security expert, specializing in space electromagnetic manipulation, mission planning, and orbital game theory. Recipient of the State Council Special Allowance, one National Teaching Achievement Award (First Prize), two Military Science and Technology Progress Awards (First Prize), and author of over 100 journal papers and multiple monographs on space security.

Cislunar space strategy

Cislunar space: new challenges for space security

Reference: Yang L, Chang M. Cislunar space: new challenges for space security[J]. China Aerospace, 2024(3): 27-31.

Abstract: With the rapid development of space technology, space economic and military activities are extending from near-Earth space to cislunar space, and international competition in cislunar space is intensifying. This paper describes the strategic value of cislunar space, analyzes the cislunar layout and development trends of major spacefaring nations, reviews the new challenges cislunar space poses for space security, and offers recommendations for attention to cislunar space security and development.

Space security development trends and impacts over the next 30 years

Reference: Yang L, Peng W. Space security development trends and impacts over the next 30 years[J/OL]. National Defense Science & Technology, 2021, 42(6): 1-4, 14.

Abstract: In recent years, the Atlantic Council, the Space Foundation, and KPMG International have published reports analyzing future space security development. Based on comprehensive analysis, this paper identifies three trends: human activities are becoming increasingly dependent on space; resource competition is moving into space; and national security is relying more heavily on space. The paper concludes that the purpose of human space activity is transitioning from "exploration and discovery" toward "commercial activation" and "security dominance," accelerating the formation of an integrated military-civilian-commercial space development pattern. Defense space innovation continues to accelerate, and cislunar space will open new frontiers for the space economy and military operations.

Cislunar low-energy transfer orbits

Design and optimization of low-energy transfer orbits via Earth-Moon L1 point

Reference: Qiao C, Yang L. Design and optimization of low-energy transfer orbits via Earth-Moon L1 point[J]. Systems Engineering and Electronics, 2024, 46(10): 3519-3527.

Abstract: Addressing the low-energy transfer problem between cislunar libration point periodic orbits and near-Earth orbits, this paper proposes a four-pulse low-energy transfer orbit design method from the Earth-Moon L1 (EML1) Halo orbit to geostationary Earth orbit (GEO). Building on the three-pulse transfer orbit design using perturbation manifolds and Lambert arc stitching, the method designs four-pulse low-energy transfers by analyzing the relationship between orbital Jacobi constant variation and velocity increment. Numerical simulations show that the four-pulse optimization model is more efficient than the three-pulse model, yielding better transfer solutions and effectively addressing the poor optimization results caused by large search spaces and numerous local extrema.

Cislunar orbital parameter characterization

Orbital parameter characterization and objects cataloging for Earth-Moon collinear libration points

Reference: Qiao C, Long X, Yang L, et al. Orbital parameter characterization and objects cataloging for Earth-moon collinear libration points[J]. Chinese Journal of Aeronautics, 2025: 103869-103896.

Abstract: Owing to the chaotic and non-integrable nature of three-body dynamics, the conventional Keplerian elements are rendered inadequate for cataloging cislunar space objects. This paper proposes a novel approach to parameterize the orbits of Earth-Moon collinear libration points by leveraging the theoretical frameworks of canonical transformations. Symplectic transformations extract 3 modes of motion from the locally linearized part, and a subsequent canonical transformation decouples the hyperbolic invariant manifold from the center manifold within the nonlinear remainder. Six characteristic parameters obtained via action-angle variables establish a bijective correspondence with the state variables. Simulation results demonstrate applicability to orbit identification and object cataloging with remarkable consistency and robustness.

Calculation of a dynamical substitute for the real Earth-Moon system based on Hamiltonian analysis

Reference: Qiao C, Long X, Yang L, et al. Calculation of a dynamical substitute for the real earth-moon system based on hamiltonian analysis[J]. Astrophysical Journal, 2025, 991(1): 46-59.

Abstract: The Earth-Moon libration points no longer exhibit the dynamical characteristics of "equilibrium points" due to perturbation effects when applying the ephemeris model. By decoupling the forced motions within the ephemeris model and computing the dynamical substitute trajectories, we can reconstruct a dynamical system that recovers the "equilibrium points" feature. This paper presents a novel method for calculating dynamical substitute based on the Hamiltonian mechanics framework. The Hamiltonian equations for the ephemeris model are formulated, the decoupling problem is reformulated as solving a nonautonomous differential equation through canonical transformations, and an iterative method based on frequency analysis is employed. Approximate analytical solutions for five libration points over a 360-year period are provided, in excellent agreement with numerical integration results.

Zhu Yanwei

Professor at NUDT, member of the CMC S&T Committee expert group, chief professor of a teaching team, chief planner of a major military project, and subsystem lead for a hardware program. Long engaged in space security research and teaching, with primary research directions in spacecraft orbital game dynamics and control, aerospace mission planning and system-of-systems simulation, and cislunar system engineering and simulation testing. Published over 40 SCI papers, 6 monographs/translations, and holds 20+ patents and software copyrights.

Space combat theory

Introduction to space operations

Reference: Zhu Y, Huang H, Cai W, et al. Introduction to Space Operations[M]. National Defense Industry Press, 2026.

Summary: This book is a systematic summary of the authors' team's years of teaching and research, organized along the main thread of "technical foundations — mission domains — command and control," featuring a prominent integration of technology and military science. It covers the basic concepts, historical development, technical foundations, mission domains, and command and control of space operations, with detailed analysis of four major mission domains: space information support, space situational awareness, space offensive and defensive operations, and space mission support. The book also discusses the impact of space law and operational doctrine on command and control, using the U.S. space operations C2 system as a reference.

Cislunar simulation system design

Intelligent simulation system architecture and implementation for cislunar space situational awareness mission design and analysis

Reference: Hu J, Zheng Q, Zhu Y, et al. Intelligent simulation system architecture and implementation for cislunar space situational awareness mission design and analysis[J]. Journal of Image and Graphics, 2025, 30(9): 2951-2965.

Abstract:
- Purpose: Cislunar orbits are characterized by long periods, strong chaos, and high sensitivity to perturbations. Cislunar situational awareness missions exhibit significant dynamic variability and uncertainty, urgently requiring advanced virtual simulation, test-bedding, and AI techniques.
- Method: A three-layer intelligent simulation system architecture — "infrastructure support + service support + typical applications" — is designed based on container cloud + microservices.
- Result: A cislunar situational awareness simulation system covering scenario design, situational awareness, mission planning, system-of-systems simulation, experiment design, and evaluation modules.
- Conclusion: The system supports forward design and iterative optimization, with 15-year resident orbit integration achieving minute-level performance under high-precision ephemeris models.

Cislunar orbital parameter characterization

Orbital parameter characterization and objects cataloging for Earth-Moon collinear libration points

Abstract: This paper proposes a novel approach to parameterize the orbits of Earth-Moon collinear libration points using canonical transformations. Six characteristic parameters via action-angle variables establish a bijective correspondence with state variables. Simulation results demonstrate applicability to orbit identification and object cataloging with consistency and robustness.

Calculation of a dynamical substitute for the real Earth-Moon system based on Hamiltonian analysis

Reference: Qiao C, Long X, Yang L, et al. Calculation of a dynamical substitute for the real earth-moon system based on hamiltonian analysis[J]. Astrophysical Journal, 2025, 991(1): 46-59.

Abstract: A novel method for calculating dynamical substitute based on Hamiltonian mechanics is presented, providing approximate analytical solutions for five libration points over a 360-year period in excellent agreement with numerical integration.

Cai Weiwei

Cislunar orbital parameter characterization

Calculation of a dynamical substitute for the real Earth-Moon system based on Hamiltonian analysis

Reference: Qiao C, Long X, Yang L, et al. Calculation of a dynamical substitute for the real earth-moon system based on hamiltonian analysis[J]. Astrophysical Journal, 2025, 991(1): 46-59.

Abstract: A novel method for calculating dynamical substitute based on Hamiltonian mechanics is presented. By decoupling forced motions within the ephemeris model and computing dynamical substitute trajectories, a dynamical system recovering "equilibrium points" features is reconstructed. Approximate analytical solutions for five libration points over a 360-year period are provided.

Hu Jiaxin

Cislunar simulation system design

Intelligent simulation system architecture and implementation for cislunar space situational awareness mission design and analysis

Abstract:
- Purpose: Cislunar situational awareness missions require advanced simulation techniques for scientific research and verification.
- Method: A three-layer intelligent simulation system architecture based on container cloud + microservices.
- Result: Full simulation system covering six modules from scenario design to evaluation.
- Conclusion: Effective support for forward design and iterative optimization with minute-level performance.

Long Xi

Cislunar orbital parameter characterization

A method for orbital parameter characterization of Earth-Moon collinear libration points

Reference: Yang L, Qiao C, Long X, et al. A method for orbital parameter characterization of Earth-Moon collinear libration points[P].

Abstract: This patent describes a method for orbital parameter characterization of Earth-Moon collinear libration points. The method transforms the circular restricted three-body problem into a chaotic Hamiltonian dynamical system, uses Legendre expansion for nonlinear terms, applies real linear symplectic transformation matrices, and defines local action-angle variables based on libration point motion modes to describe spacecraft motion on the center manifold.

Orbital parameter characterization and objects cataloging for Earth-Moon collinear libration points

Abstract: A novel approach to parameterize the orbits of Earth-Moon collinear libration points using canonical transformations. Six characteristic parameters establish a bijective correspondence with state variables. Applicable to orbit identification and object cataloging.

Calculation of a dynamical substitute for the real Earth-Moon system based on Hamiltonian analysis

Reference: Qiao C, Long X, Yang L, et al. Calculation of a dynamical substitute for the real earth-moon system based on hamiltonian analysis[J]. Astrophysical Journal, 2025, 991(1): 46-59.

Abstract: A Hamiltonian mechanics framework for computing dynamical substitutes of the real Earth-Moon system, providing approximate analytical solutions for five libration points over 360 years.

Chang Meichen

Cislunar space strategy

Cislunar space: new challenges for space security

Reference: Yang L, Chang M. Cislunar space: new challenges for space security[J]. China Aerospace, 2024(3): 27-31.

Abstract: With the rapid development of space technology, space economic and military activities are extending from near-Earth space to cislunar space. This paper describes the strategic value, analyzes major nations' cislunar layouts, reviews new challenges for space security, and offers recommendations.