Nasa removes US astronaut from ISS mission
Dr Epps was to have been the first African-American astronaut assigned to the space station crew.
She would have flown aboard a Russian Soyuz flight in June but is being replaced by another astronaut.
Nasa has not given a reason for withdrawing her but says she will be considered for future missions.
Jeanette Epps, born in Syracuse, completed a doctorate in aerospace engineering in 2000. After graduating, she worked in a laboratory for two years before being recruited by the Central Intelligence Agency (CIA).