Joseph Acaba

Joseph Acaba (born May 17, 1967, Inglewood, California, U.S.) is an American astronaut who, over three spaceflights to the International Space Station (ISS), has spent 306 days in space. He is part of the Artemis team of astronauts who are eligible to fly to the Moon in the mid-2020s.

Acaba received a bachelor’s degree in geology from the University of California at Santa Barbara in 1990 and a master’s in the same subject from the University of Arizona in 1992. He worked in Los Angeles as a hydrogeologist on the cleanup of Superfund sites. He then served in the Peace Corps in the Dominican Republic from 1994 to 1996 as an environmental education awareness promoter. He was manager at the Caribbean Marine Research Center on Lee Stocking Island in The Bahamas. He also served in the United States Marine Corps Reserve.

In Florida Acaba taught science at Melbourne High School from 1999 to 2000 and mathematics and science at Dunnellon Middle School from 2000 to 2004. He was selected by NASA in 2004 as part of a class of 11 astronaut candidates. In that group, Acaba was one of three “educator astronauts”—teachers who meet all the qualifications to be an astronaut and have educational outreach as part of their responsibilities.

Acaba’s first spaceflight was the STS-119 mission on board the space shuttle Discovery, which launched to the ISS on March 15, 2009. He performed two space walks, moving equipment as part of the station’s final stages of construction. STS-119 spent more than 12 days in orbit and returned to Earth on March 28.

Acaba’s next two flights to the station were long-duration flights. He launched to the ISS on Soyuz TMA-04M on May 15, 2012, and spent 124 days in orbit. He received a master’s degree in education from Texas Tech University in 2015. Acaba returned to the ISS on Soyuz MS-06 on September 12, 2017. He made one space walk, replacing cameras on the station exterior. Acaba’s flight also marked the beginning of a special “Year of Education” on the ISS, in which he and educator astronaut Richard Arnold (who flew to the ISS after Acaba’s return) performed demonstrations and spoke with students. Acaba spent a further 168 days in orbit.

Acaba was chosen in 2020 for the team of 18 astronauts eligible to fly in the Artemis program, which is to return American astronauts to the Moon for the first time since 1972. On the Artemis III mission, scheduled for 2026, two astronauts are to land on the lunar surface. Those astronauts, whom NASA has said will be the first woman and the first person of color on the Moon, are to spend almost a week in the Moon’s south polar region. Acaba became chief of the Astronaut Office at NASA in 2023.