Researchers from the University of Arizona have investigated the mineral compositions of two near-Earth asteroids (NEAs), finding potential iron, nickel and cobalt resources exceeding Earth’s global reserves.
The asteroids – named 1986 DA and 2016 ED85 – present similar spectral signatures to our solar system’s largest metal-rich body, 16 Psyche.
Lead author on a research paper for The Planetary Science Journal, Juan Sanchez, said the asteroids were a window to both the Earth’s and the solar system’s history.
“Our analysis shows that both NEAs have surfaces with 85 per cent metal such as iron and nickel and 15 per cent silicate material, which is basically rock,” Sanchez, said
“These asteroids are similar to some stony-iron meteorites such as mesosiderites found on Earth.”
The report detailed the estimated weight of each metal in an average iron meteorite and 1986 DA.
This figure equated to 2.84 x 1010 or 28.4 billion metric tons (25.75 billion tonnes) of iron and 2.48 billion metric tons of nickel.
Co-author David Cantillo put these astronomical figures into perspective when compared to their even larger origins.
“We believe that these two ‘mini Psyches’ are probably fragments from a large metallic asteroid in the main belt, but not 16 Psyche itself,” Cantillo said.
“It’s possible that some of the iron and stony-iron meteorites found on Earth could have also come from that region in the solar system too.”
Associate professor at the University of Arizona Vishnu Reddy is the principal investigator of the NASA grant which funded the research.
Reddy said this paper was a long time coming for her and the team.
“We started a compositional survey of the NEA population in 2005, when I was a graduate student, with the goal of identifying and characterizing rare NEAs such as these metal-rich asteroids,” Reddy said.
“It is rewarding that we have discovered these ‘mini Psyches’ so close to the Earth.”