Special feature on cosmochemistry engineer Professor Grenville Turner, who worked with Apollo missions

Professor Grenville Turner with some of his family at May's Mayor-Making ceremony when he received Honorary Citizenship of his home town at Todmorden Town Hall
Professor Grenville Turner with some of his family at May's Mayor-Making ceremony when he received Honorary Citizenship of his home town at Todmorden Town Hall

Todmorden people are justifiably proud of the contribution some of its citizens have made to the world’s understanding of science.

They often mention the contributions made to the fields of physics and chemistry respectively by Nobel prizewinners Sir John Cockcroft and Sir Geoffrey Wilkinson but until this year they may not have been as aware of the work of Professor Grenville Turner in the field of cosmochemistry, in which he was a pioneer, developing dating techniques which have revealed much about our solar system.

It meant he was involved with the National Aeronautics and Space Administration (NASA) Apollo space mission projects at a time when these gripped the world’s imagination in the late 1960s and early 1970s, being one of a number of scientists who were allocated some samples of moon rock gathered by the Apollo 11 mission, which landed the first men on the moon in July 1969, to analyse.

Although now formally retired, Prof Turner, who lives in Sheffield where he taught for many years, continues to study the history of the solar system, for which his interest has been described as “infectious” - inspirational to succeeding generations of scientists. He is Professor of Isotope Geochemistry at Manchester University’s Department of Earth Sciences.

In May he was awarded Honorary Citizenship of Todmorden to recognise his work, joining a select few who have received the accolade, a ceremony which he attended with his wife Kate and members of his family. They have a daughter, Charlotte, son, Patrick, and grandchildren William, Emily, Ruby and Finlay.

A career which has brought him great recognition in the world of science had its humbler begins in Todmorden, where Prof Turner grew up attending Shade School and then Todmorden Grammar School, his interest sparked at a young age.

“I suppose it developed as a result of books I got as Christmas presents, a couple of which I still have. One called ‘How It Works And How It’s Done’ sums up what attracted me. At school I was inititally attracted to chemistry but then in the sixth form found physics more interesting because it seemed to aim at the fundamental basis behind things. I also enjoyed maths which is absolutely essential for all areas of science and especially physics.

“My physics master Herbert (Harry) Green was a big influence, as was my chemistry master in the sixth form, Mike Bowker. He isn’t much older than me and is still living in Malvern,” he said.

Having completed a degree at St John’s College, Cambridge, he arrived at Balliol College, Oxford, as a graduate student in nuclear physics. His research at the time had little to do with space but that was all to change.

“Nuclear physics was a popular avenue to follow in the late 50s but in retrospect I was lucky in choosing a project outside the mainstream,” he says.

He was tasked with designing and building a new kind of mass spectrometer in stainless steel to measure helium isotopes produced in nuclear reactions using a particle accelerator at Harwell - something which also taught him to be independent and solve problems.

“In the final year I got it all to work and with my DPhil went off to the University of California in Berkeley to work with John Reynolds. He had built the world’s first ultra high vacuum mass spectrometer, made of glass, in 1956 and used it to discover evidence for an ‘extinct’ isotope, iodine-129, in a primitive meteorite. It was the first of a dozen or so since discovered that tell us about the processes and timing of element building in stars before our solar system was formed.

“Since those early days a new field of ‘isotope chemistry’ has evolved making use of nuclear physics and physical chemistry to use natural isotopes as a key to understanding geological processes and the evolution of the Earth and planets,” said Prof Turner.

After two years he retruned to Sheffield University where he describes himself as something of a “one-man band” in cosmochemistry. A flash of inspiration led to what is now one of the most commonly used methods for dating rocks, argon dating.

As he was refining the technique, NASA put out a call for scientists to work on the Apollo missions, and with the support of Reynolds, Prof Turner became a principal investigator.

“The samples were originally low on NASA’a priority list which naturally enough was more concerned with engineering and astronaut safety. Like other university scientists I submitted a proposal to say what I would do if I was allocated some bits of moon rock. This is how most of the sample work was done and is still being done. In 1969 no-one else was using my dating method, so my proposal to apply it to moon rocks was successful.

“In my career I’ve worked mainly on using naturally occurring noble gases and other isotopes to understand processes going on in meteorites, the Moon, Mars and of course the Earth,” he said.

In 1970-71 he was also able to spend to time at Caltech - the California Institute of Technology - as a result of his work on dating the Apollo 11 samples, which he had presented at the first Lunar Science Conference in Houston, Texas, in January 1970.

“I jumped at the chance as I wasn’t getting much support in the UK from the Science Research Councilo. At Caltech, in a lab calling itself the Lunatic Asylum, we were very close to the action. The leader of the Caltech group was one of several senior scientists who spent a lot of time urging NASA to set up ‘clean labs’ in good time to document the lunar samples and distribute them to scientists,” he said.

Moving aside any conspiracy theories, the techniques prove the Americans did go to the Moon, said Prof Turner. “Isoptopes are powerful tools and, for example, show it would be impossible to forge moon rock. Even if the forger could generate or find basalts of a convincing chemical composition on Earth, the isotopes would give the game away in a million different ways.

“So the Americans did go to the Moon, no question!” he said.

Prof Turner says the lunar work stimulated a lot of new ideas about the earth and the specialised techniques and “clean labs” people developed prior to Apollo had a big spin-off when applied to the earth’s geology. “I’ve given courses in planetary geology which have taken advantage of all the new data and ideas coming out of NASA missions to the Moon and planets,” he said.

Well-recognised in the scientific world - he is a Fellow of the Royal Society, a Fellow of the Meteoritical Society, a Fellow of the Geochemical Society and European Association of Geochemistry and a Fellow of the Geophysical Union - he was delighted to receive Honorary Citizenship of his home town, something he wished his mother Florence could have seen.

“It came completely out of the blue and was totally unexpected. I was extremely pleased of course, and my only regret was that it came just three years after my mother died. I told a story at the presentation about an American scientist I knew who was given an important medal by the American Geophysical Union. When the person making the presentation finished, saying how well deserved the award was, my friend receiving the medal said ‘my father would have appreciated that and my mother would have believed it’” he said.