Millie Elizabeth Hughes-Fulford was an American molecular biologist, medical investigator, and payload specialist who became the first woman to fly in space in that role. Born on December 21, 1945, in Mineral Wells, Texas, she spent a career linking laboratory science to the practical problems of human spaceflight. She died of lymphoma on February 2, 2021, at her home in Mill Valley, California, at the age of 75.
She grew up in a small Texas town and later said that childhood science fiction, including the television series Buck Rogers and its character Wilma Deering, helped fix her attention on space. She graduated from Mineral Wells High School in 1962 and entered college at sixteen. In 1968 she received a bachelor of science degree in chemistry and biology from Tarleton State University in Stephenville. She then began graduate work in plasma chemistry at Texas Woman’s University in Denton as a National Science Foundation Graduate Fellow from 1968 to 1971, and she was also an American Association of University Women fellow from 1971 to 1972. She earned her doctorate in 1972.
After completing her degree she joined the faculty of Southwestern Medical School at the University of Texas in Dallas as a postdoctoral fellow with Marvin D. Siperstein, studying the regulation of cholesterol metabolism. When Siperstein moved his laboratory to the San Francisco Veterans Affairs Medical Center, Hughes-Fulford followed. That move set the institutional base for the rest of her scientific life. From 1981 until 1995 she also served in the United States Army Reserve Medical Corps, rising to the rank of major.
Her path into the astronaut corps began with a public call for candidates. In 1978 she answered an advertisement, reported in accounts of her life as appearing in Family Circle magazine, seeking applicants to become the first American woman in space. Roughly eight thousand people applied. Hughes-Fulford reached the final group of about twenty before NASA selected Sally Ride, who flew on Challenger in 1983. The process nonetheless brought her to the attention of scientists looking for bone and biomedical researchers. NASA selected her as a payload specialist in January 1983 for the Spacelab Life Sciences program. Her flight was delayed after the Challenger disaster in January 1986 halted the shuttle program. She waited eight years between selection and launch.
On June 5, 1991, she lifted off aboard the space shuttle Columbia on STS-40, the Spacelab Life Sciences 1 mission, the first shuttle flight devoted primarily to biomedical research. She was NASA’s first female payload specialist and the first representative of the Department of Veterans Affairs to fly in space. The seven-person crew included three women, the first time that had happened on a NASA mission. Columbia completed 146 orbits, traveled more than 3.2 million miles, and returned on June 14. Official accounts put the mission duration at nine days, two hours, and fourteen minutes, or 218 hours, 14 minutes, and 20 seconds. The crew carried out more than eighteen experiments and returned more medical data than any previous NASA flight. Subjects included the astronauts themselves, rodents, and jellyfish. The work documented how microgravity affects the human body, from fluid shifts and cardiovascular changes to immune and musculoskeletal responses.
That single flight defined the scientific agenda she pursued for the next three decades. After returning she directed the Hughes-Fulford Laboratory at the San Francisco VA Health Care System and held a faculty appointment in biochemistry and biophysics at the University of California, San Francisco. She served for a time as scientific adviser to the Under Secretary of the Department of Veterans Affairs. Her laboratory examined how weightlessness alters gene expression, T-cell activation, and the growth of bone-forming cells. She was principal investigator on a series of SpaceHab and Biorack experiments that flew on STS-76, STS-81, and STS-84, work aimed at the cellular roots of the bone loss astronauts experience and at related questions in osteoporosis. Later experiments, conducted with NASA and the European Space Agency, studied changes in T-cell gene induction and flew to the International Space Station, including a 2006 station experiment and later immunology work associated with a SpaceX cargo flight. In 2013 NASA recognized related findings among top discoveries from the station. Over her career she contributed to more than 120 papers and abstracts on T-cell activation, bone regulation, and cancer cell growth.
The practical importance of that research is easy to understate. Long-duration flight weakens bone, alters immune function, and changes how cells respond to signals that on Earth would trigger growth or defense. Hughes-Fulford’s experiments treated those changes as measurable biology rather than as vague side effects of being in orbit. By comparing cells and crew members in microgravity with ground controls, her groups helped show that some genes fail to activate normally when immune cells are stimulated in weightlessness, a finding with implications for infection risk on future missions and for understanding immune regulation more generally. The bone-cell studies similarly connected the rapid skeletal loss seen in astronauts to regulatory pathways that also matter in ordinary osteoporosis.
She remained active late in life. In 2018 she helped establish the UC Space Health program based at UCSF, an effort to organize university research around the medical problems of spaceflight. Colleagues later noted that she approached her own lymphoma, diagnosed in 2014, with the same analytical habit she brought to the laboratory, including discussion of how her treatment might be modified. Cancer was eventually found in her esophagus as well. Her daughter, Tori Herzog, confirmed the cause of death.
Her personal life intersected with the long wait for a flight. A first marriage, to Rick Wiley, produced her daughter and ended in divorce in the late 1970s. In 1983 she married George Fulford, a United Airlines captain. NASA biographical notes list recreational interests that included scuba diving, swimming, gardening, photography, computer graphics, and boating. Honors over the years included selection as Federal Employee of the Year for the Western Region in 1985, recognition as an International Zontian in 1992, and Marin County Woman of the Year in 1993. She also served on boards connected to space research and science writing.
Hughes-Fulford’s place in space history is specific rather than symbolic. She was not the first American woman in orbit; that was Sally Ride. She was the first woman to fly as a payload specialist, a category reserved for scientists whose experiments justified their presence, and the first VA scientist to do so. The distinction matters because STS-40 was designed as a laboratory, not as a demonstration of access alone. The mission’s volume of biomedical data, and the follow-on experiments she sent to later shuttles and to the station, extended that laboratory role well beyond nine days in 1991. For students of both space medicine and the slower opening of technical careers to women from outside the traditional pilot track, her path from a Texas high school to a VA bench to Columbia’s middeck is a concrete record of how one investigator turned a childhood interest in space into a body of evidence about what weightlessness does to human cells.
CONCLUSION
Fly in space like free bird.