Astronaut Jeanette Epps will be staying on Earth this year. In early 2017, NASA announced Epps was scheduled to make history in 2018 as the first African-American astronaut to work as a crew member on the International Space Station.
A new NASA announcement this week notes Epps is no longer on the roster for the May launch.
Serena Auñón-Chancellor, who was originally set to visit the ISS later in 2018, will take Epps' place.
The space agency says Epps "will return to NASA's Johnson Space Center in Houston to assume duties in the Astronaut Office and be considered for assignment to future missions."
NASA does not comment on its reasons for reassigning astronauts. "A number of factors are considered when making flight assignments; these decisions are personnel matters, for which NASA doesn't provide information," NASA spokeswoman Brandi Dean said.
NASA selected Epps as an astronaut in 2009. She has a doctorate in aerospace engineering and has been through extensive science and technical training in preparation for an eventual space station mission. Epps was a backup crew member for ISS Expedition 54/55, which launched in December.
While there have been no African-American crew members during the space station's nearly 20-year history, there have been African-American astronauts in space on shuttle missions.
The success of the book and 2016 movie adaptation of "Hidden Figures" raised public awareness of the contributions made by African-American women to NASA. Epps' reassignment doesn't mean she won't still travel to the ISS at some point in her career.
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