Almost a year ago, the space science community observed a fascinating event when an asteroid entered Earth's orbit, circling our planet for nearly two months before departing. Scientists actively track such asteroids due to the potential risks they pose to life on Earth. However, these celestial bodies also present immense opportunities, as they are believed to contain precious metals worth billions of dollars. This duality has sparked interest among space entrepreneurs and scientists, who are gearing up for the next asteroid visit with the intention of capturing and mining these space rocks.
Most asteroids orbit the sun within the asteroid belt located between Mars and Jupiter. Importantly, many of these asteroids are rich in metals that are essential for modern technology, including platinum, cobalt, iron, and even gold. NASA has estimated that the metals found in these asteroids could be valued at approximately $100 million for every person on Earth. Capturing and mining just ten of the most profitable asteroids could yield a staggering $1.5 trillion, raising the critical question: Can we access these valuable resources?
Last year, the powerful gravity of Jupiter sent an asteroid named 2024 PT5 hurtling through the solar system, ultimately entering Earth's orbit. This asteroid, sourced from the Arjuna asteroid belt situated around 93 million miles (150 million kilometers) from the sun, was dubbed a "mini-moon." Although the term is used loosely—mini-moons are typically expected to complete a full orbit around Earth—2024 PT5 exited our gravitational pull before accomplishing a full trip. Nonetheless, it mirrored our moon's orbit and was abundant in rare earth metals, heightening interest in its potential mining.
While asteroid samples have been successfully returned to Earth for research—thanks to missions like NASA's OSIRIS-REx and Japan's Hayabusa2—the costs associated with these journeys range from $10 million to $150 million per gram of material, making it financially unfeasible for companies aiming to profit from mining. The high price tags are largely due to the distance of most asteroids from Earth, which leads to exorbitant fuel and equipment costs. This is where mini-moons, like 2024 PT5, become more appealing targets for asteroid mining.
Last year's sighting of the mini-moon spurred numerous space-mining startups to devise plans for capturing future asteroid visits. Joel Sercel, founder and CEO of TransAstra, emphasized the potential of mining mini-moons, stating, "If we had our systems up and running, we could go and get it." He outlined a vision where a spacecraft could capture an asteroid and place it in a stable orbit, providing a permanent resource in space. However, there's a significant hurdle: experts have noted that fewer than ten mini-moons have been spotted in the last decade, leading to uncertainty about their availability for mining.
Reaching asteroids presents numerous challenges, including extreme temperatures and radiation, complicating missions. According to Mustafa Hassanalian, an associate professor at the New Mexico Institute of Mining and Technology, these factors make any mission to an asteroid complex. While about a dozen small asteroids orbit Earth at any given time, most are not large enough to warrant a mining expedition. Yet, mini-moons are considered the right size for economic feasibility. The primary challenge lies in locating them.
A team at the Vera C. Rubin Observatory, which houses the world's largest digital camera, has expressed optimism about advances in asteroid detection. The observatory's recent images could pave the way for improved identification of mini-moons, making space mining a more attainable goal.
Currently, Chinese companies dominate the global market, controlling between 80-90% of rare earth metal exports. This has prompted private companies in the U.S. and elsewhere to seek new sources from unconventional locations, including asteroids. Essential materials like copper for wind turbines, nickel for solar panels, and platinum for hydrogen fuel cells are abundant in certain asteroids. Historically, most rare materials on Earth originated from asteroid impacts, but heavier elements have since sunk into the Earth's core, leaving only trace amounts accessible for mining.
The first unintentional asteroid 'soft landing' occurred when NASA's NEAR Shoemaker touched down on asteroid Eros in 2001. The mission concluded prematurely due to cold conditions, but it marked a significant milestone. Japan followed with its Hayabusa missions, and NASA's OSIRIS-REx recently returned samples on September 24, 2023. Looking ahead, China's Tianwen-2 is set to return asteroid samples by 2027, further fueling interest in asteroid mining.
Despite these advancements, the asteroid mining industry has yet to flourish. Asteroids spin rapidly, complicating landing and extraction efforts. Sercel explains that current spacecraft do not actually land on asteroids due to their low gravity. Instead, companies are exploring methods to harvest metals without direct contact. For example, Tethers Unlimited has developed a concept involving a net to capture asteroids, though funding challenges have stalled progress.
TransAstra's approach involves using concentrated sunlight to break apart a water-rich asteroid. Their method includes deploying a giant plastic bag around the asteroid and using a sophisticated magnifying device to melt the ice, leaving behind valuable metals. Although TransAstra missed the opportunity with 2024 PT5, their focus remains on future mini-moon visitors, which may appear over the next few years.
NASA's upcoming Psyche mission, slated for launch in 2029, aims to explore a metal-rich asteroid of the same name. This mission could revolutionize our understanding of asteroids and potentially set the groundwork for the first interstellar industry. According to Lindy Elkins-Tanton, the lead scientist on the mission, the asteroid 16 Psyche could be worth quadrillions of dollars, raising concerns about its potential impact on the global economy.
Despite the potential riches offered by asteroid mining, the industry faces significant challenges, including high costs and technical complexities. With continued investment and advancements in technology, the dream of mining asteroids may one day become a reality. However, until then, the majority of asteroid mining technology will remain in the realm of aspirations and innovations, waiting for the right moment to take flight.
