Selected by NASA in June 1998, Caldwell Dyson reported for training in August 1998.
Her Astronaut Candidate Training included orientation briefings and tours, numerous scientific and technical briefings, intensive instruction in Shuttle and International Space Station (ISS) systems, physiological training, ground school to prepare for T-38 flight training, as well as learning water and wilderness survival techniques.
Completion of this training and evaluation qualified her for flight assignment as a mission specialist.

In 1999, Caldwell Dyson was assigned to the Astronaut Office ISS Operations Branch as a Russian Crusader, participating in the testing and integration of Russian hardware and software products developed for ISS.
In 2000, she was assigned prime Crew Support Astronaut for the ISS Expedition 5 crew, serving as their representative on technical and operational issues throughout the training and on-orbit phase of their mission.

During ISS Expeditions 4 through 6, Caldwell Dyson also served as an ISS spacecraft communicator (CAPCOM) inside Mission Control.
In 2003, she made a transition to the Astronaut Shuttle Operations Branch and was assigned to flight software verification in the Shuttle Avionics Integration Laboratory (SAIL) and also worked supporting launch and landing operations at Kennedy Space Center, Florida.
Caldwell Dyson also served as Lead CAPCOM for Expedition 11.

Caldwell Dyson was assigned to, and later flew on STS-118, Space Shuttle Endeavour, on August 8–21, 2007, which was the 119th space shuttle flight, the 22nd flight to the station, and the 20th flight for Endeavour.
Caldwell Dyson was assigned as Mission Specialist #1 on this flight.
During the mission Endeavour's crew successfully added another truss segment, a new gyroscope and external spare parts platform to the International Space Station.
A new system that enables docked shuttles to draw electrical power from the station to extend visits to the outpost was activated successfully.
A total of four spacewalks (EVAs) were performed by three crew members.
Endeavour carried some 5,000 pounds of equipment and supplies to the station and returned to Earth with some 4,000 pounds of hardware and no longer needed equipment.
Traveling 5.3 million miles in space, the STS-118 mission was completed in 12 days, 17 hours, 55 minutes and 34 seconds.
Finally, during the flight of STS-118, Caldwell Dyson celebrated her 38th birthday in space.

On April 4, 2010, Caldwell Dyson joined the Expedition 23 crew aboard ISS.
She lifted off on April 2, 2010 from the Baikonur spaceport aboard a Russian Soyuz capsule (Soyuz TMA-18).
After 176 days duty as part of the Expedition 24 crew, she returned to Earth with the Soyuz TMA-18 landing unit.
She has completed three spacewalks, logging more than 22 hrs of EVA including work to replace a malfunctioning coolant pump.
Together with commander Aleksandr Skvortsov and flight engineer Mikhail Korniyenko, Dyson landed in Kazakhstan on September 25, 2010.

In a television interview on the 40th anniversary of the first moon landing, she said she is the first astronaut who was born after Apollo 11.

As Tracy Dyson, she is the host of a series on NASA TV called StationLife, which focuses on facets of life aboard the International Space Station.

She appeared on Episode 3 of MasterChef Junior Season 4.

On March 21, 2017, Dyson stood behind President Trump as he signed a bill for NASA to send humans to Mars in 2030s and receive $19.5 billion in 2018 funding.
Dyson and fellow NASA astronaut Chris Cassidy presented Trump with an official flight jacket during the ceremony.
Selected by NASA in June 1998, Caldwell Dyson reported for training in August 1998. Her Astronaut Candidate Training included orientation briefings and tours, numerous scientific and technical briefings, intensive instruction in Shuttle and International Space Station (ISS) systems, physiological training, ground school to prepare for T-38 flight training, as well as learning water and wilderness survival techniques. Completion of this training and evaluation qualified her for flight assignment as a mission specialist.
In 1999, Caldwell Dyson was assigned to the Astronaut Office ISS Operations Branch as a Russian Crusader, participating in the testing and integration of Russian hardware and software products developed for ISS. In 2000, she was assigned prime Crew Support Astronaut for the ISS Expedition 5 crew, serving as their representative on technical and operational issues throughout the training and on-orbit phase of their mission.
During ISS Expeditions 4 through 6, Caldwell Dyson also served as an ISS spacecraft communicator (CAPCOM) inside Mission Control. In 2003, she made a transition to the Astronaut Shuttle Operations Branch and was assigned to flight software verification in the Shuttle Avionics Integration Laboratory (SAIL) and also worked supporting launch and landing operations at Kennedy Space Center, Florida. Caldwell Dyson also served as Lead CAPCOM for Expedition 11.
Caldwell Dyson was assigned to, and later flew on STS-118, Space Shuttle Endeavour, on August 8–21, 2007, which was the 119th space shuttle flight, the 22nd flight to the station, and the 20th flight for Endeavour. Caldwell Dyson was assigned as Mission Specialist #1 on this flight. During the mission Endeavour's crew successfully added another truss segment, a new gyroscope and external spare parts platform to the International Space Station. A new system that enables docked shuttles to draw electrical power from the station to extend visits to the outpost was activated successfully. A total of four spacewalks (EVAs) were performed by three crew members. Endeavour carried some 5,000 pounds of equipment and supplies to the station and returned to Earth with some 4,000 pounds of hardware and no longer needed equipment. Traveling 5.3 million miles in space, the STS-118 mission was completed in 12 days, 17 hours, 55 minutes and 34 seconds. Finally, during the flight of STS-118, Caldwell Dyson celebrated her 38th birthday in space.
On April 4, 2010, Caldwell Dyson joined the Expedition 23 crew aboard ISS. She lifted off on April 2, 2010 from the Baikonur spaceport aboard a Russian Soyuz capsule (Soyuz TMA-18). After 176 days duty as part of the Expedition 24 crew, she returned to Earth with the Soyuz TMA-18 landing unit. She has completed three spacewalks, logging more than 22 hrs of EVA including work to replace a malfunctioning coolant pump. Together with commander Aleksandr Skvortsov and flight engineer Mikhail Korniyenko, Dyson landed in Kazakhstan on September 25, 2010.
In a television interview on the 40th anniversary of the first moon landing, she said she is the first astronaut who was born after Apollo 11.
As Tracy Dyson, she is the host of a series on NASA TV called StationLife, which focuses on facets of life aboard the International Space Station.
She appeared on Episode 3 of MasterChef Junior Season 4.
On March 21, 2017, Dyson stood behind President Trump as he signed a bill for NASA to send humans to Mars in 2030s and receive $19.5 billion in 2018 funding. Dyson and fellow NASA astronaut Chris Cassidy presented Trump with an official flight jacket during the ceremony.
Tracy Caldwell Dyson