Mark Geyer said May 3 he was stepping down as director of the Johnson Space Center after three years to focus on his cancer treatment, but would remain with the agency as a senior adviser. Credit: NASA/JSC

WASHINGTON — The head of NASA’s Johnson Space Center is stepping down from his post because of health issues, but will remain with the agency as an adviser.

In a three-minute video published May 3, Mark Geyer announced that he would leave the position of director of the Houston-based center in order to focus on treatment for an unspecified cancer diagnosed a year ago.

“I’ve been dealing with cancer for about 12 months, the symptoms and mitigations, and given that the treatment has no clear end in sight, I made the decision that it was time to step down,” he said. “This job is more than a full-time job, and even though [deputy director] Vanessa [Wyche] and my staff and others in the leadership have backed me up when necessary, it’s really clear now that I need to focus on the treatment.”

Geyer became director of JSC in May 2018 after serving as acting deputy associate administrator for technical in NASA’s Human Exploration and Operations Mission Directorate at NASA Headquarters. He previously was deputy director of JSC and a longtime manager of the Orion program.

NASA said in a statement that Geyer will remain with the agency as a senior adviser to the associate administrator. “Under Mark’s leadership, Johnson has moved the United States into a new era of human space exploration,” Bill Nelson, who was sworn in as NASA administrator earlier in the day, said in the statement. “We’re fortunate to continue to have Mark and his decades of expertise serving the agency in his new role.”

Wyche, the deputy director of JSC since August 2018, will serve as acting director of the center. She joined NASA in 1989 and held positions that included director of the center’s exploration integration and science directorate and being flight manager for several shuttle missions.

“She’s going to do a terrific job,” Geyer said of Wyche in the video, citing her work leading the center’s response to the pandemic. “She’s ready to do this job. She has a passion for JSC and for NASA, and she’ll do great things, I’m sure.”

Geyer noted in the video that when he took over as director in 2018, he expected stay on the job for five years or so, “because I thought that was a reasonable amount of time to come in, understand the job and then to make a difference.”

He cited the accomplishments of the last year, from getting the Orion spacecraft ready for the Artemis 1 launch to successful commercial crew missions. He also noted transitions for the center in the year ahead, including gradually resuming on-site work as the coronavirus pandemic ebbs. “It will be different from what it was before. It will be a hybrid,” he said.

“Transitions are really a part of our history, and it’s part of how NASA grows and remains a leader,” he said.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...