Cape Town - As mining companies struggle with the falling price of precious metals, the answer may lie in looking up.
One such company looking to tap space mining is US-based Planetary Resources, which is focused on asteroids as viable targets for precious metals.
The space rocks, which are the remains of the formation of the solar system, may contain higher concentrations of precious metals that can be mined efficiently.
"Distance to the asteroid is not as important as its composition because it's all relative in the amount of energy needed, which is why the company’s goal is to prospect potentially viable targets to determine what resources could be extracted," Stacey Tearne, vice president of communications at Planetary Resources, told Fin24.
Asteroids are roughly categorised into three classes according to Nasa: C-, S- and M-type, named for their composition. The primary targets for a mining project would be M-type bodies because of their higher metal composition.
"A fleet of spacecraft will travel to potential targets to validate the composition and other characteristics. The spacecraft will have special sensors that operate over a wide spectral range beyond traditional visible wavelength sensors to achieve these goals," said Tearne.
Unlike Earth where deep mines are drilled to extract precious metal ore, heavy metals are thought to be evenly distributed throughout asteroids.
Planetary Resources calculates that a "1km diameter asteroid could contain about 7 500 tons of platinum".
On Earth, falling commodity prices have added pressure to the bottom-line of mining companies. Gold has dropped from a high of $1 220 an ounce in June to $1 088/oz in August.
It's much the same trend for silver and platinum over the last three months.
Watch this YouTube video on how asteroid mining might work to extract precious metals:
Beyond using robots to mine for metals, S-type asteroids, which are more common than target M-type, represent way stations for deep space operations.
"While less likely to contain hydrated minerals, silicates represent a potential source of building material and radiation protection for commercial and government space operations," said Planetary Resources which plans to launch its Arkyd Spacecraft in December 2015.
In theory, once space operations are under way, companies could save significantly as automated mining returns minerals to Earth.
Furthermore, a number of Near Earth Objects (NEOs) regularly pass earth, reducing the expense of having to travel far out to space to capture an asteroid.
Data from Nasa shows that on August 5 and 6, four objects will come within 28 423 595km of Earth.
But mining space objects for precious metals does not violate international treaties on space, said Tearne.
"The plan to mine asteroids does not violate the Outer Space Treaty of 1967 as Planetary Resources does not seek to lay claim to any celestial body as a whole. In fact, recent passage of the Space Resources Exploration and Utilisation Act of 2015 (Space Act) by the US House of Representatives grants the ownership of minerals from space to the entity that extracted them."
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