You can’t see it, you can’t smell it, but without neodymium, hardly anything would function in a modern spacecraft – and indeed, in our everyday lives on Earth. Neodymium, an element with atomic number 60, is an invisible powerhouse, belonging to the group of lanthanides and collectively known as “rare earths.”
However, this name is one of chemistry’s great misnomers: neodymium is almost as common in the Earth’s crust as copper or nickel. The problem with rare earths is not their scarcity, but their distribution. Neodymium, for example, is almost never found in concentrated veins but is finely dispersed within mineral ores. Its extraction is therefore an industrial feat, making neodymium one of the most valuable strategic raw materials of the 21st century.
Chemical Heavy Lifting: The Separation Problem
The reason neodymium is so difficult to extract lies in its chemical nature. It usually occurs together with its “siblings,” mostly praseodymium or dysprosium. Since these elements behave extremely similarly chemically, they cannot be separated from each other by simple melting processes.
Instead, hundreds of extraction steps are necessary in gigantic cascade plants, involving highly aggressive acids and toxic solvents. These processes generate enormous quantities of toxic by-products. Particularly unpleasant is the radioactive sludge that can result, as rare earths are often associated with thorium.
This is also the reason for the current Chinese monopoly on rare earths: almost 90% of global processing takes place in China, as the infrastructure has been built there over decades, and environmental standards played a subordinate role for a long time. While mines like Mountain Pass in the USA or the Mount Weld Mine in Australia extract the raw ore, the material often has to travel across the Pacific to Chinese factories for final refining.
The Muscles of Robotics: Why Neodymium in Particular?
What makes neodymium indispensable for space travel? The answer lies in the NdFeB alloy (neodymium-iron-boron). This compound enables the production of the strongest permanent magnets currently available to humanity. A neodymium magnet can lift a thousand times its own weight.
In zero gravity and the extreme conditions of space, every gram counts. Neodymium magnets make it possible to build motors that generate enormous power with minimal size and low weight. However, the motors and devices used in space must not only be lightweight.
The motors must also operate with extreme precision, as the robotic arms of Mars rovers like Perseverance must be able to collect samples with microscopic accuracy. Neodymium-powered stepper motors provide the necessary torque without exceeding the rocket’s payload capacity with heavy components.
Without neodymium, ion thrusters also remain an illusion. These futuristic propulsion systems are key for all long-range missions. They accelerate xenon ions to extreme speeds in an electromagnetic field. Neodymium magnets help to focus and stabilize the plasma. This is a task that conventional ferrite magnets could never accomplish due to their weaker field strength.
Highly efficient sensors also cannot do without neodymium: hundreds of sensors on the ISS monitor life support systems. Wherever magnetic fields are used for position determination or flow measurement, a small core of neodymium is present.
The West in the Rare Earth Trap
Neodymium has long been more than a chemical element; it is a geopolitical currency. The West’s dependence on Chinese supply chains is often referred to as the “rare earth trap.” China has shown in the past, for example during the trade dispute with Japan in 2010, that it is willing to use rare earth export quotas as political leverage.
For companies like Honeywell, Northrop Grumman, or Thales Alenia Space, this is a nightmare scenario that poses significant dangers. A sudden, sustained Chinese supply halt could cripple their own production of satellites and defense systems for years. Exploring Mars or establishing a lunar base is virtually impossible without a steady flow of these magnets.
The Long Road Back to Independence: Recycling and New Horizons
The world has taken a long time, but it has now understood the Chinese wake-up call. Europe and the USA are desperately trying to build their own rare earth supply chains. The discovery of massive deposits in Kiruna, Sweden, in early 2023, or projects in Greenland, offer new hope. However, opening a mine and establishing the associated chemical industry often takes ten to 15 years.
In parallel, recycling is increasingly coming into focus. So far, less than one percent of rare earths are recovered from old devices, as the magnets are often firmly glued or screwed into the housings. Innovative start-ups are working on processes to recover neodymium from old hard drives and electric motors using bacteria or special acids.
Thus, there is no doubt: neodymium is the silent hero of the modern era. It enables us to transcend the boundaries of our planet and send robots to alien worlds. Yet, our yearning for the stars is inextricably linked to the dirty and complex realities of earthly mining politics.
Only if we succeed in making the extraction and processing of neodymium more sustainable and independent will the path to the stars remain permanently open. Without this “invisible magnetism,” our bold dreams of space travel literally remain grounded – at least for now.
