Mineral mining in space is one of the popular topics in science fiction, computer games dedicated to space, as well as in the works of various futurist scientists. Let’s deal with how realistic is the extraction of minerals outside the land currently.
First let’s figure it out in the point of view of cosmic field physics. Shakhtar equipment is expensive and weighs a lot. The mass of the middle rig is measured with tens of tons. At the same time, we sit at the bottom of the gravitational well of the Earth and to raise the cargo from the surface of the Earth, even at a low-seater orbit, you need to spend a lot of energy.
Saturn-5 used for lunar missions was the most lifting rocket in the history of astronautics. The mass of Saturn was 3000 tons and the rocket could withdraw 150 tons (less than 5% of the mass) to a low-seated orbit, and in the orbit of the moon — only 50 tons of payload.
If we are talking about sending using such a missile weight to the belt of asteroids, the amount of payload will decrease even stronger, because even more fuel will be required. In this case, Tsiolkovsky’s missile equation is a stubborn thing. If we construct a rocket twice as much as Saturn-5, this will not mean that we will double and useful weight that such a rocket is able to transport, because the rocket will have to spend fuel to carry with it and additional Fuel supply!
Of course, it is possible to raise the equipment to a low-seater orbit for several launches and there already build a large spacecraft for flight to the astonoid belt and let us do it.
The belt of asteroids is between the orbits of Mars and Jupiter and lies about the boundaries 2.2 to 3.2 astronomical units from the Sun. One astronomical unit, remind, is equal to the distance from the ground to the Sun, i.e. Approximately 150 million kilometers.
The distance from the ground to the nearest edge of the belt of asteroids is 1.2 A.E. (180 million km), but most likely we will have to fly further and hardly an object that we need will lie on the land axis — the sun. It will increase the travel time.
In addition, when we already arrive at the asteroid you need between us and the Earth will constantly change due to the fact that the mutual arrangement of the asteroid and land during their orbital movement will change.
Thus, the trip to the accidentally taken asteroid can occupy how much time in the interval between 9 months and a few years. In practice, this means that the spacecraft must be very large to carry not only the crew, but also the system of life support, as well as the reserves of provisions and water for the multi-month or even many years of stay away from the ground.
Send a robotic station for mining at the current level of technology development is not possible. The development of a robot, which will be able to independently find mineral deposits, develop them, load the mined fossils in the spacecraft and send to Earth the task is extremely difficult to implement and probably more complicated than sending people on the ship.
Then, let’s say we flew to the belt of asteroids. Which asteroid to choose? The average distance between objects in the belt of asteroids is about a million kilometers. At the same time, less than one percent of the objects of the asteroid belt was investigated. We know the orbits of all more or less large objects in the belt, but on this our knowledge of it is essentially ends.
Want to believe, you want no — we do not have the slightest idea where in the belt asteroids to search for minerals. Here everything is on earth. We can not just stick a shovel or a burden to the ground and find what we need. Mineral deposits have to be sought using geological intelligence. Thus, for the success of the mineral mining mission in the belt of asteroids, we will need to lay the time and equipment for geological exploration on asteroids.
Suppose we found minerals on asteroids. Let it be gold and mined a large number of golden ore. Golden ore must be enriched, i.e. Separate gold from mineral impurities. On earth for this, special processing equipment is used. It will also have to drag with him that even more will increase the mass of the spacecraft and, as a result, the cost of the conclusion of this entire orbit and the achievement of the belt of asteroids.
Suppose we somehow managed to clean 100 tons of gold. Now you need to spend a lot of fuel to bring this gold back to the ground. If only we do not come up with some kind of way to make fuel directly on the asteroid, then the fuel will need to carry with them from the ground from the very beginning.
Let’s summarize. We need to carry with you: mining equipment, crew, supplies, geological exploration, processing equipment, a huge stock of fuel. Total for the most modest assessment, the mass of the payload, which will need to be launched into the orbit of the Earth, to organize such a mission will be at least 2-3 thousand tons.
Okay, let’s say we delivered 100 tons of gold back to the ground. Now the kilogram of gold costs about $ 42 thousand. The appearance of 100 tons of gold on the market will collapse the price of gold times in two, if not more, but let’s say the price is $ 42 thousand. The output of 2000 tons in orbit will cost approximately $ 40-60 billion, and from the sale of 100 tons of gold will be able to help out well if 4-5 billion, provided that prices are not collapsed. But we did not even consider how much the equipment for the flight will cost.
Thus, no, using current mining technologies in the belt of asteroids cannot be advantageous economically.
There are several conditions that, in case of their execution, can make mining outside the Earth appropriate.