She was a brilliant rocket scientist who followed her husband from job to job and took eight years off from work to raise three children.
"The world's best mom," her son Matthew said.
Yvonne Brill, who died March 27 at 88 in Princeton, N.J., of breast cancer, in the early 1970s invented a propulsion system to help keep communications satellites from slipping out of their orbits.
The system became the industry standard, and it was the achievement President Barack Obama mentioned in 2011 in presenting her with the National Medal of Technology and Innovation.
Her personal and professional balancing act also won notice. In 1980, Harper's Bazaar magazine and the DeBeers Corp. gave her their Diamond Superwoman award for returning to a successful career after starting a family.
Mrs. Brill -- she preferred to be called Mrs., her son said -- is believed to have been the only woman in the United States who was actually doing rocket science in the mid-1940s, when she worked on the first designs for an American satellite.
It was a distinction she earned in the face of obstacles, beginning when the University of Manitoba in Canada refused to let her major in engineering because there were no accommodations for women at an outdoor engineering camp, which students were required to attend.
"You just have to be cheerful about it and not get upset when you get insulted," she once said.
Mrs. Brill's development of a more efficient rocket thruster to keep orbiting satellites in place allowed satellites to carry less fuel and more equipment and to stay in space longer. The thrusters have the delicate task of maneuvering a weightless satellite that can tip the scales at up to 5,000 pounds on Earth.
Mrs. Brill contributed to the propulsion systems of Tiros, the first weather satellite; Nova, a series of rocket designs that were used in American moon missions; the Atmosphere Explorer, the first upper-atmosphere satellite; and the Mars Observer, which in 1992 almost entered a Mars orbit before losing communication with Earth.
From 1981 to 1983, Mrs. Brill worked for NASA developing the rocket motor for the space shuttle.
Yvonne Madelaine Claeys was born on Dec. 30, 1924, in St. Vital, a suburb of Winnipeg, Manitoba. Her parents had separately immigrated from Flanders, in Belgium. Her father was a carpenter.
After the University of Manitoba barred her from the engineering program, she studied mathematics and chemistry instead and graduated at the top of her class. Her lack of an engineering degree did not prevent her from getting a job with Douglas Aircraft in Santa Monica, Calif.
She never received a professional engineer's license, but did pick up a master's in chemistry at the University of Southern California while working as a saleswoman for a chemical company. Afterward she went to work for Douglas, whose satellite project became the foundation of the RAND Corp., an early research center. It was at RAND that she worked on the first American satellite designs, remaining there for three years.
While still peddling chemicals, she met William Franklin Brill, a research chemist, at a talk by Linus Pauling, who would win one of his Nobel Prizes in chemistry. They married in 1951. William Brill died in 2010.obituaries