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It is rocket science

- Wits University

His plan to mine asteroids secures big win for alumnus Jonathan Lun.

The Wits alumnus and rocket scientist has won Singularity University’s Global Impact Challenge Southern Africa for 2017.

His win is a big deal. Lun will be spending two months at SingularityU’s campus at the NASA Research Park in Mountain View, California, US, on a full sponsorship to attend the transformational Global Solutions Program where he will get the mindset, tools, and network to help create moonshot innovations that will positively transform the future of humanity.

Moonshot innovations

According to SingularityU’s website, the definition of a moonshot innovations is somewhere between bold thinking and science fiction: “Moonshot thinking involves taking aim at a global challenge, ideating radical solutions that can otherwise seem like the stuff of science fiction, and then leveraging some initial validation or tangible breakthrough that could make the solution achievable in the not-too-distant future.”

Lun is a senior engineer at Denel Spaceteq and holds PhD in Mechanical Engineering from Wits University. According to tech blog,, Lun is one of just a handful of people globally working on a revolutionary propulsion system that could lead to humankind’s ability to mine asteroids in the future.

Extract from

Asteroid mining is a perennial topic that comes up in sci-fi stories and think-tank papers as a way of improving access to raw metals for Earth-bound industries. Some believe that as mines run dry on Earth, they could be the only source of some materials in the future. A single 300m long asteroid, Lun says, could yield enough iron to keep South Africa’s metalworkers going for a year. One 30m long asteroid is believed to hold $50bn of platinum.

One challenge that has to be overcome before asteroid mining is remotely feasible, however, is getting mined materials back to Earth – and in particular, fuelling rockets for the return journey. A rocket loaded up with enough fuel for both outward and inward legs of the journey would probably be too heavy to take off in the first place, or at least prohibitively expensive no matter what value of metals it returned.

And this is where Lun comes in. He’s published papers looking at the feasibility of a “vacuum arc thruster” for powering a mining craft. Vacuum arc thrusters create thrust via plasma jets by pulsing electricity between two electrodes (an anode and a cathode), and burn up the cathode as fuel.

Lun’s theory is that if a vacuum arc thruster can be built that’s big enough, a mining vessel could propel itself back to Earth by burning up some of the metal’s it’s extracted as that cathode.

And it’s very much a theory right now. While Lun has built tiny prototypes to show how existing models of vacuum arc thrusters can be improved, it’ll be many years before they’re ready for testing in even the smallest satellite, he says. Read the full article on

He told that "sometimes we don’t realise it's a problem until a solution is found. Sometimes a solution is too late by the time the problem occurs (e.g. massive global climate change). In other words, prevention is often better than a cure." Read the full interview on