WASHINGTON — A NASA astronaut removed early this year from a mission to the International Space Station said Oct. 29 that she still doesn’t understand the reasons for her reassignment.

Jeanette Epps was assigned by NASA in January 2017 to the crew of Expeditions 56 and 57, scheduled to launch to the station on a Soyuz spacecraft in mid-2018. It was to be the first spaceflight for Epps, a member of the 2009 astronaut class, and the first long-duration mission to the ISS by an African-American astronaut.

However, NASA announced last January that Epps would be replaced by Serena Auñón-Chancellor, who had been training for a later mission to the station. 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,” the agency said in a statement at the time, but offered no other explanation for her removal from the mission. That mission launched in June with Auñón-Chancellor along with Alexander Gerst of ESA and Sergey Prokopyev of Roscosmos, and the three are currently the sole crew on the ISS.

Epps, appearing in an on-stage interview at a Center for Strategic and International Studies event here, said that more than nine months after the reassignment, she still doesn’t know why she was taken off the crew, noting that it was not a medical-related decision.

“I really haven’t found out much information lately, so we’re still kind of working through those issues and figuring out what’s going to happen for the future,” she said. She added that “several things that have happened on the space station recently” slowed that effort, an apparent reference to the hole discovered in the Soyuz MS-09 spacecraft docked to the station in August and the Soyuz MS-10 launch abort earlier this month.

The original announcement of Epps’ removal from the flight in January generated speculation that the Russians had opposed her inclusion on the flight, as well as allegations of racism. Epps, who was completing training in Russia at the time of her reassignment, said she had seen no signs of problems with the Russians she worked with on a daily basis.

“My work with the Russians was always very friendly, very warm, going through all of the training,” she said. “I can’t say anything negative about the training that I got there. So I wouldn’t say that the Russians had anything to do with this.”

“Whether race played an issue,” she continued, “I don’t know what’s in the minds of other people. I can’t say definitely or anything like that. So, I’m not quite sure of the reasons myself.”

Epps said that, since her removal from the mission, she returned to Houston and resumed activities there, such as getting recertified to fly on the T-38 aircraft used by NASA for astronaut training. “I’m still hoping” to get assigned to another mission, she said.

“Things happen, but how you deal with them is important,” she said when asked how she was dealing with the situation. “You can go on merit for a long time, but understanding the culture of any organization that you’re in is going to come into play at some point.”