Who was Katsuko Saruhashi? Google commemorates feminist geochemist who helped clear dangerous nuclear experiments from the seas

Saruhashi's commitment to inspiring other women scientists was as remarkable as the work she did herself

Google is honouring Katsuko Saruhashi, a Japanese scientist who did pioneering work in her field – and then inspired many more like herself to do the same.

Saruhashi's list of achievements is vast and wide. Chief among them is work she did to test how nuclear fallout was moving in the seas, and use it to show that tests of nuclear explosions in the ocean should be limited.

But Saruhashi's achievements weren't only scientific, and the list of work that others went on to do as a result of her inspiration is even longer. She also worked incredibly hard to ensure that other women got a chance to make the breakthroughs she did, explaining that it was her mission to make the field she worked in more equal.

"There are many women who have the ability to become great scientists," she said. "I would like to see the day when women can contribute to science & technology on an equal footing with men.”

Her work in that area has been recognised with, among many others things, a prize named in her honour. When she retired in 1980, her colleagues gave her five million yen – and she used that money to establish the Association for the Bright Future of Women Scientists, which has rewarded Japanese women scientists working in the natural scientists with a prize every year since.

Google recognised all of those achievements in its Doodle, which was displayed across the world. "Today on her 98th birthday, we pay tribute to Dr. Katsuko Saruhashi for her incredible contributions to science, and for inspiring young scientists everywhere to succeed," it wrote on its page.

Before she did the work she would go on to be remembered for, Saruhashi was already breaking through barriers. She was the first woman to earn a doctorate in chemistry from the University of Tokyo in 1957, for instance, and she would continue such achievements by becoming the first woman to win a prestigious geochemistry award.

But the work that would define her scientific life was begun after the US started testing nuclear weapons at Bikini Atoll. In response to that, the Japanese government wanted to know whether exploding the warheads was affecting the water in the ocean and in rainfall, and commissioned the Geochemical Laboratory, where she worked, to analyse that.

She made use of the understanding of accurately measuring water but turned it to explore the way nuclear fallout spread through the water. She found that the pollution was taking a long time to make its way through the ocean – but that eventually it would spread out and mix with the water, moving across the world.

It was those findings and others like it that helped contribute towards stopping the test of nuclear warheads in the ocean. And it was some of the first work that explored the way that nuclear fallout spreads over the world – a field that would go on to become terrifyingly relevant in accidents like those at Chernobyl or Fukushima.

Saruhashi would go on to explore the other dangers posed by rain and water, including work on acid rain.