## 1 Introduction  
There is pressure around the world to urgently find alternative low-emission sources. New technological and business models for extracting mineral resources must also be developed to make mining a more sustainable and green industry. Moreover, there are raw materials (e.g., Rare Earth Elements (REE) and Platinum Group Elements (PGE)) that are critical for the development of modern technologies but are running out or controlled by a group of several countries [1] (China, India, Russia, Malaysia). Space mining offers a chance to solve many of these problems. Given the current state of technological development, not all space resources are equally accessible and promising. The imagination of scientists and businessmen is fired up by the possibility of obtaining mineral resources from asteroids, which would not require interference in Earth's ecosystems. Some asteroids, at the current level of consumption of mineral resources, could provide a source of some metals (PGE, Fe, Co, and Ni) even for thousands of years [2], and the value of the raw materials they contain may even reach many billions of dollars. The Asterank online database [3] provides a ranking of asteroids in terms of their estimated market value. This is a scientific and economic database of over 600,000 asteroids. Other estimates can be found in paper [4]. Of course, these estimates are based on our current knowledge of the formation and composition of individual types of asteroids, and often on measurements of light reflected from their surfaces, which do not provide information about their internal structure. This results in high uncertainty in the estimates of the content of mineral resources accumulated in asteroids, and therefore also in their market valuation. The Luxembourg Space Agency in its 2018 report [5] predicts that by 2045 there will be between 845,000 and 1.8 million full-time employees working in the space mining industry. Not all of them will work in space--some of them will work on Earth, e.g., in the design, construction and servicing of mining equipment, remotely control the operation of devices, etc. However, the exploitation of raw materials from asteroids involves many technical challenges. Microgravity occurring on asteroids eliminates the possibility of using many mining techniques and devices known on Earth, which require gravity to operate. Examples of such devices that require gravity to function properly include wheeled vehicles, excavators, bulldozers, drilling and impact devices, gravity separators, conveyors transporting excavated material, and robot arms. The lack of gravity changes the dynamics of these devices, often making it difficult for them to function correctly or effectively. The devices must also have a high degree of autonomy and reliability, which can be a significant technical challenge. For example, during drilling typical borehole in oil and gas industry on Earth, many potential failures and drilling complications can occur [6; 7] and some of them can occur also during drilling in space objects like planets and asteroids. Robotic mining equipment sent to asteroids that would use drilling methods (e.g., to collect samples) would have to be able to detect and respond to many known and unknown failures and technological problems, which would require the development of highly advanced control systems. The time scale of the project is also unacceptable to potential investors. We currently do not have the drives that would enable us to reach distant asteroids in a short time. For example, a trip to Mars takes minimum seven months [8] and requires waiting for the launch window, which appears once every two years. Asteroids rich in raw materials are much further away. What does this mean from an economic point of view? The first mission is unlikely to be successful. Raw materials also need to be brought back to Earth. This extends the time horizon for returns on investments from space mining operations on asteroids to 10 years or longer.