## 5 Structure  
In the S-C-P framework, the structure is understood as the relatively stable, firm aspects of the sector that rule the sector players' conduct (strategies) and, therefore, sector performance. On the other hand, the structure is conditioned by astrophysical and geopotential conditions as well as by supply and demand; cf. the modified S-C-P model (Figure 2). The S-C-P model originates from the applied microeconomics strand called Industrial Organization (IO). Thus, the structure originally relates to the level of competition within an industry, considering factors such as concentration, product differentiation, and barriers to entry [11; 12]. However, the implicit assumption is that some kind of market already exists. That was not, and to some extent still is not, the case in the space economy. According to the Cambridge Dictionary, structure denotes \"the way in which the parts of the system or object are arranged or organized\" [62]. The basic elements of the space economy are governments, businesses, and citizens/customers. These parts could be connected by the government-led and centrally controlled activities focused on pursuing public priorities or by market forces. \"Space is a place: one in which, (...) both the government and market forces will play essential complementary roles\" [38] (p. 1). Their roles and engagement evolved over time. This is an economic problem in establishing the abovementioned structure and the ideal proportions between the government and the market. [PERSON] and [PERSON] expressed it in the claim they call the \"First Fundamental Theorem of Welfare Economics\", namely, \"under certain conditions, using the decentralized market to organize activity makes the most of the resources we have. (...) Those conditions include: the absence of externalities, the ability to trade all goods and services, and all participants being rational, informed price-takers\" [38] (p. 4). Following this idea, our analytical framework's structure is understood more broadly than typically in the S-C-P model. Only the last condition above refers directly to the main question of the orthodox interpretation of the structure, namely if there is market power (allowing it to be a price-maker) in the sector, thus defining the structure as perfect competition or imperfect competition (monopolistic competition, oligopoly/monopoly, oligopsony/monopsony, bilateral monopoly, etc.). Historically, the space economy has been predominantly driven by government initiatives. During the mid-20 th century, national space agencies spearheaded space exploration, focusing mainly on national security and, to some extent, on scientific research. Publicly funded civil space agencies were tasked with overseeing space infrastructure development to support national and international programs. Initially, they focused on directly procuring, managing, and operating space systems. Then, some of them, like NASA, started to focus primarily on policy and program coordination while outsourcing operational responsibilities to specialized third parties. These agencies typically finance the full lifecycle of space system development through large-scale research, development, and technology initiatives. Similarly, military space agencies are responsible for developing and operating defense-related space assets. While their function mirrors that of civil space agencies, their primary focus is national security and defense applications. In such a way, governments created (and still create in a large proportion) the midstream demand for space infrastructure secured by upstream activities, namely the space manufacturing segment, comprising launch subsystem, spacecraft subsystem, and ground subsystem [2; 38]. The earliest satellites (1950s) were purely government-funded and non-commercial, serving military needs. It was Telstar 1 (1962)--a joint venture between NASA and AT&T--that introduced the first commercial transatlantic satellite TV broadcast.