Christine Cole Catley: Bright Star: Beatrice Hill Tinsley Astronomer

Beatrice Tinsley's discoveries are the key to much that is known today.

This was a book that nearly didn't get written, and without it the story of the New Plymouth girl who answered the big questions of the universe would have been little more than a footnote to New Zealand history.

Beatrice Hill Tinsley's life work was the evolution and formation of galaxies. Before she proved that the universe was still evolving, conventional wisdom had held galaxies to be immobile and unchanging.

Her discoveries are the key to much of what is known today, yet she is little known in New Zealand.

When Cole Catley was approached by Tinsley's father, Edward Hill, to write his daughter's biography, she turned him down. Her background was in the arts, not the sciences, and she felt that only an astronomer could do it justice.

It's a good thing she changed her mind. Drawing on personal letters and interviews with family, friends and colleagues, Cole Catley draws a portrait of an incredibly gifted scientist who was also a woman who touched the lives of everyone she met.

Born seven weeks premature in England after a German air raid during World War II, Tinsley came to New Zealand at the age of 5 with her family.

Her intelligence was clear from a young age, but there was little inkling that she would go on to greatness. Her achievement was even more remarkable given her provincial upbringing - her school, New Plymouth Girls' High, did not even teach the sciences properly at the time.

At home, Beetle, as she was known, felt insecure. While her childhood was never tumultuous, it lacked warmth. Mother Jean was emotionally distant, and her beloved Nanny Gullidge was sent away early in her life.

She nevertheless remained a dutiful daughter, always "doing the right thing". It was this moral compass that guided many decisions later in life, even when her heart and mind were set down another road.

She married fellow scientist Brian Tinsley in 1961, but realised early on that they were ill-suited. She soldiered on in the marriage, her ambitions often taking a back seat to being a mother and wife.

In 1963, they moved to Dallas, Texas, where Brian had been offered a teaching position. There she set about completing her PhD thesis in record time, despite having to commute hundreds of kilometres each week to Austin. During this time they adopted their first child, Alan, followed a few years later by daughter Terry.

While Brian's career took flight at Dallas, she was held back, largely by chauvinism. She failed to land full-time work, despite the acknowledged brilliance of her PhD thesis.

She got by with whatever part-time work she could secure, and despite raising two children almost single handedly, she still managed to publish a prodigious number of papers.

Over time, however, her discontent in Dallas grew, and she left her children and husband on Christmas Day 1974, "all three of them sitting in a sea of ribbons and cards and Christmas paper".

She was viewed as callous and uncaring by others, but Cole Catley paints a different picture of a woman torn between family and her almost unquenchable thirst for knowledge.

Perhaps influenced by her emotionally unavailable mother, Tinsley emerges, too, as a woman divorced from her emotions.

Her decision to leave on Christmas Day was driven by inexorable logic that the children would be preoccupied with presents and would scarcely notice her departure. Little did she consider that Christmas for them would be forever marred.

But her altruistic intentions never dim in Cole Catley's portrayal. When Brian threatened to fight for the children in court, she simply decided to let him have custody because a protracted legal battle would not be good for the children.

Tinsley had become a professor of astronomy at Yale when she died of cancer in 1981, at only 40. Her life had shone brightly, but dimmed too soon.

Cole Catley has given shape to the life of a great New Zealander. What emerges is a picture of a woman trapped by her time, struggling to prove her worth in a male-dominated field while trying to meet society's expectations as a mother and wife - and all the while seeking answers to the big questions of the universe.

* Published by Cape Catley Ltd