A Montana State University astrophysicist has won a prestigious international award for her pioneering work on neutron stars.


Sachiko Tsuruta will receive the Marcel Grossmann Prize on July 13 during the Marcel Grossman Meeting in Rome.  Grossman was a mathematician who collaborated with Albert Einstein, and his namesake meetings focus on the latest developments in gravitation and general relativity.  The Grossmann award is given every three years.

“We’re all thrilled for her,” said MSU solar physicist David McKenzie. “To be recognized for a fundamental discovery is awesome.”

Yves Idzerda, head of MSU’s Department of Physics, said, “Montana State University once again stands in good company.”

The other individual winners this year are astrophysicists at Princeton University, Trinity College-Cambridge and the University of Tokyo. Previous winners included several Nobel Laureates, as well as famed cosmologist Stephen Hawking.

“It’s very nice,” Tsuruta said of her prize.

In the 51 years since Tsuruta received her Ph.D. from Columbia University, she has investigated a variety of topics that deal with dense stellar objects, such as neutron stars, black holes, white dwarfs, supermassive black holes and early universe problems such as first stars, gravitational waves and gamma ray bursts.

Her most important contribution to astrophysics is said to be her prediction that neutron stars existed. She made that prediction as a doctoral student and before pulsars were discovered in 1967. Pulsars are highly magnetized rotating neutron stars. Tsuruta also made predictions about the cooling and heating of neutron stars. Her predictions have since been proven true by the Hubble Space Telescope, ground-based telescopes and telescopes in X-ray satellite missions.

Tsuruta’s findings have been published in more than 230 papers and shared in more than 330 lectures at national and international conferences. She has served on organizing committees of several major conferences, including the third and seventh Marcel Grossmann meetings.

During the upcoming Grossman meeting, Tsuruta will give a lecture titled, “How hot neutron stars are.”

Some people might think neutron stars are cold, but they are very hot compared to ordinary stars, she said.

“The problem is essentially calculating the temperature of neutron stars and comparing them with the observed data,” Tsuruta said.

Knowing more about the cooling mechanism of neutron stars allows scientists to answer a variety of questions, such as the composition of their cores, Tsuruta said.

A native of Yokohama, Japan and the granddaughter of a Shinto priest, Tsuruta said she became a scholar because of her father. She became an astrophysicist after moving to the United States.

Her father was interested in history and wanted to become a scholar, but after college he went to work for the makers of Kirin beer and encouraged all six of his daughters to pursue higher education. His only son died as a toddler.

Tsuruta majored in English in Japan, but she switched to astrophysics after transferring to the University of Washington. Explaining, she said she couldn’t compete with English majors in the United States, but mathematics is the language of physics, and any nationality can speak it. She had enjoyed physics and astronomy in high school.

Tsuruta earned her bachelor’s degree from the University of Washington and her master’s and doctoral degrees from Columbia University. She then worked for the Smithsonian and Harvard Observatory, now the Harvard Center for Astrophysics. She also became an outside adviser to NASA. For several years, she commuted between MSU and Germany, working half a year at MSU and half a year at the Max Planck Institute in Munich. She started working full-time at MSU in 1989.