— NASA has named its 19th chief astronaut.

Scott Tingle, who spent 166 days on the International Space Station in 2018 and was next to command the first operational flight of Boeing's Starliner spacecraft until that mission ran into delays, is succeeding Joe Acaba as the head of NASA's astronaut office.

Tingle's appointment was noted in an email to employees at the Johnson Space Center by center director Vanessa Wyche. Due to the ongoing federal government shutdown there was no press release or statement released, as is typical when a new chief is chosen.

Acaba, who held the position since February 2023, is joining Wyche's staff to provide "technical advisement for mission and strategy" at Johnson. Under this new role, he will also support "the agency's STEM [science, technology, engineering and mathematics] workforce goals... [and] will advance the center's collaboration with commercial space, academia, and other government agencies as we explore beyond Earth orbit," wrote Wyche.

Acaba was one of NASA's first educator-astronauts selected in 2004. In addition to holding a master's degree in geology and having worked as a hydrogeologist, he also earned a master's degree in education and was a middle school and high school science and math teacher before reporting to the space agency.

As chief, Tingle will now lead the 40 active U.S. astronauts in the corps and 10 candidates in training, as well as coordinate missions with the international astronauts from Canada, Japan and the United Arab Emirates who train as part of NASA's human spaceflight program.

Tingle will oversee the assignment of astronauts to future missions, including commercial flights to the International Space Station and Artemis missions to orbit and land on the moon. NASA has yet to name the Artemis III crew, who the agency intends to become the first humans to land on the moon since Apollo 17 astronauts Gene Cernan and Harrison Schmitt departed the lunar surface in 1972.

Tingle joined the astronaut corps in 2009 as a member of the 20th astronaut class, nicknamed "The Chumps." A captain in the U.S. Navy and a naval aviator (call sign "Maker"), he earned a master's in mechanical engineering with a specialty in fluid mechanics and propulsion from Purdue University.

In December 2017, Tingle joined Anton Shkaplerov of Roscosmos and Norishige Kanai of JAXA (Japan Aerospace Exploration Agency) on Russia's Soyuz MS-07 mission to the International Space Station. As an Expedition 54/55 flight engineer aboard the ISS, he helped conduct hundreds of science experiments and captured and released four visiting cargo spacecraft. Tingle also conducted a seven-hour, 24-minute spacewalks to service the station's Canadarm2 robotic arm.

Among Tingle's ISS Expedition 54 crewmates was Acaba, and they both were part of NASA's Year of Education on Station.

In 2022, NASA announced that Tingle would fly as the commander of Starliner-1, Boeing's first operational crewed mission to the space station, targeted then for launch in early February 2023. A preceding crew flight test, however, encountered significant thruster issues, resulting in further delays. NASA reassigned the Starliner-1 crew and the flight is now tentatively planned for sometime in 2026 at its earliest.

The position of chief astronaut was first created for and held by Mercury astronaut Deke Slayton in 1962 (the formal title "chief astronaut" or "chief of the astronaut office" was not established until late 1963, when Alan Shepard took over the role).

The prior chief astronauts have included: Slayton (1962-1963); Shepard (1963-1969); Thomas Stafford (1969-1971); Shepard (1971-1974); John Young (1974-1987); Dan Brandenstein (1987-1992); Robert "Hoot" Gibson (1992-1994); Robert Cabana (1994-1997); Ken Cockrell (1997-1998); Charles Precourt (1998-2002); Kent Rominger (2002-2006); Steven Lindsey (2006-2009); Peggy Whitson (2009-2012); Robert Behnken (2012-2015); Christopher Cassidy (2015-2017); Patrick Forrester (2017-2020), Reid Wiseman (2020-2022) and Joe Acaba (2023-2025).