Advertisement
Advertisement

Space-loving dentist gets his teeth into precision mission to Mars

Adrian Wan

A Hong Kong dentist with a lifelong fascination for the night sky is using the skills he learned in filling cavities to help the search for life on Mars.

Dr Ng Tze-chuen, 58, has designed and developed a precision tool for ExoMars, a two-mission collaboration between the European Space Agency and Nasa scheduled for Mars in 2016 and 2018.

'No professions in the world, not even astrophysicists, have more experience in micro-manipulation of minute powder than dentists,' he said. 'It's got nothing to do with engineering. It may indeed be rocket science, but it's a piece of cake.'

Using his 40 years of dental experience, Ng designed a machine for flattening the rock samples that will be taken from two metres below the surface of the Red Planet during the phase of the mission scheduled for 2018.

After other machines on the mission's rover exploratory vehicle retrieve and grind the rock, Ng's invention will crush the resulting powder into a very thin, flat surface. That will make it easier to perform the detailed chemical, physical and spectral analyses vital for understanding the evolution and habitability of Mars.

The device is based on two dental tools he has used every day for decades: the condenser for filling cavities and the carver for shaping.

'One of the many things dentists have to do is to fill patients' teeth using amalgam and shape these fillings carefully so they fit comfortably with their other teeth,' Ng said.

But these are hand tools. He had to figure out how to automate them.

Ng thought of different ways to achieve the desired flatness: by sliding a blade over the powder, for example, or by pressing a piston into the powder; or with a combination of both. He eventually decided on a motor-driven piston.

Dr Wolfgang Schulte, of German astronautics firm Kayser-Threde GmbH, said a test in the company's Munich laboratories showed Ng's device achieved better flatness than other designs.

The German company invited Ng to design the device in 2008 in view of his experience, passion and track record. The ExoMars project isn't the dentist's first reach into space.

For the ill-fated British Beagle 2 mission in 2003, Ng designed a set of forceps to collect soil and rock, but the device never saw action.

The Beagle 2 lost contact with Earth soon after leaving the Mars Express mother ship on Christmas Day 2003.

Schulte, who has worked with Ng for almost a decade, praises his 'spirit of invention, his strong commitment and enthusiasm to get involved in space exploration, and his willingness to support our work, even on his own funds'.

Indeed, Ng gets no money from the space companies or agencies. He digs into his own pocket to fly around the world and do the research and development needed for his projects.

'My day job is rather boring,' he said, 'but I'm glad it's allowed me to indulge my real passion.'

He has had that passion since his childhood. The stars fascinated him and he remembers being captivated by the first moon landing in 1969, which he watched on television.

While Ng was studying at the Royal Dental Hospital in London, he designed and patented a dental instrument for which he won several prizes.

Years later, when he saw on television how clumsily astronauts performed tasks while wearing thick gloves in zero gravity, his mind lit up with a flurry of inventions. He developed a complete set of tools for use inside space vehicles.

He began by modifying traditional dental forceps, eventually creating a complete kit of 70 interrelated tools for a range of experiments in space. The Russians adopted the modified forceps on the Mir space station in the mid-1990s.

The rock grinder and corer aboard the Beagle 2's Mars Express was a modified version of some of the kit's early elements.

Since then Ng has travelled to the worlds' space agencies more than 300 times. He is now talking to India.

Ng said there were times out on the road, living in cheap hotels, when he got despondent and thought about giving it all up.

But after a few days he bucks up and carries on in his usual enthusiastic way.

Not all his inventions succeeded. Prototypes turned down by leading space agencies, including Nasa, now adorn his surgery in Causeway Bay.

Space isn't his only interest. Among other projects, he is working on a robotic arm to explore whatever is behind a mystery door in the so-called Queen's chamber in the Great Pyramid in Egypt.

His wife, Amanda, usually supports his space obsessions. His elder son and daughter are studying medicine in Britain - despite attempts to channel them into Egyptology and astronomy - and a younger daughter is also in Britain at secondary school.

Ng has reduced his dental workload and sees only a few patients a day, spending most of his time inventing exploratory tools. 'I love cool gadgets,' he said. 'I am always wondering how tools we are using now can be improved. But of course, not while I'm filling teeth.'

Asked why he was the only dentist in Hong Kong, or even the world, to be involved in such projects, he said: 'Many of them are more interested in money. I daydream about the universe. I imagine what goes on in outer space.'

His daydreams tell him that life exists on Mars - not in the popular notion of humanoid aliens, but as bacteria.

He has no doubt. 'It is definite there is life, either past or present, on Mars because there is water deep under the Martian ground,' he said. 'Where there is water, there is life. The global aim now is to find it.'

Post