Research of the Sun, planets and small bodies of the Solar System with the help of automatic interplanetary probes and descent vehicles is one of the prioritized areas of international fundamental space research. Modern space technology is characterized by structures operating under conditions of intense, often extreme, thermal influences. The general trend in the development of technology is associated with an increasing number of critical heat-loaded technical objects, with a tightening of conditions for their thermal loading with a simultaneous increase in reliability and lifetime and a decrease in material consumption. For spacecraft and planet probes the maintenance of thermal conditions is one of the most important tasks of design, which determines the main structure solutions. The characteristic features of modern heat-loaded structures of space technology are nonstationarity, nonlinearity, multidimensionality and the conjugate nature of heat and mass transfer processes. These features limit the opportunities to use traditional computational and experimental research methods. Thermal Protection Systems (TPS) of re-entry vehicles and Thermal Control Systems (TCS) of spacecraft function are under significant thermal loads, therefore, they must be optimally designed both in terms of technology and mass characteristics. The development of TPS and TCS is a complex scientific and technical problem since the thermal regime of spacecrafts determines the reliability of the structure and onboard systems and significantly affects the success of the entire scientific mission. It is necessary to solve a set of problems associated with stringent requirements to minimize their weight and costs already at the initial design stage. Designing such systems involves a widespread use of methods of mathematical modeling. However mathematical modeling is impossible without reliable information about the characteristics (properties) of analyzed materials and heat transfer processes. In most practical cases direct measurements of thermal and radiative properties of materials (especially of complex composition) are impossible. The only way to overcome these complications is to make indirect measurements. A mathematically similar approach is usually formulated as a solution to the inverse problem: by direct measurements of the state of the system (temperature in particular), determination of properties of the analyzed system for example thermal and radiative characteristics of materials, heat transfer coefficients etc. Violation of causal relationships in the formulation of such problems leads to their illposedness in mathematical sense (i.e. the lack of existence and/or uniqueness and/or stability of the solution). Therefore to solve this kind of problems we must develop special methods which are usually called the regularizing ones. The goal of this work is to develop a set of experimental and mathematical means of a system to identify mathematical models of Heat Transfer in Thermal Protection of re-entry vehicles and Thermal Control Systems of a spacecraft. And a new technique of thermal analysis of aerospace structure that has been developed is a combination of sufficiently accurate measurements and ultimately correct mathematical treatment of experimental data based on the theory of inverse problems.