Seven astronauts will be strapped inside the space shuttle Discovery for lift-off, but it will be a bit roomier for the ride back home.
European Space Agency astronaut Thomas Reiter is staying behind on the International Space Station for what is expected to be a 145-day mission.
Here's a look at the crew of the shuttle mission launching on July 1.
- Commander Steven Lindsey, a 45-year-old father of three, is in charge of the five-man, two-woman crew assigned to Nasa's second post-Columbia flight.
Raised in Temple City, California, Lindsey attended the US Air Force Academy, where he earned a Bachelor of Science degree in engineering sciences, then studied at the Air Force Institute of Technology for a master's in aeronautical engineering.
A distinguished test pilot and squadron commander, Lindsey was selected as an astronaut in 1995. He has made three previous flights aboard the shuttle, twice as a pilot and once as the commander.
- Pilot Mark Kelly, 42, of West Orange, New Jersey, is a familiar face at Nasa. His identical twin brother is also an astronaut.
Kelly joined the US Merchant Marine as a naval aviator after graduating from the Merchant Marine Academy in 1986.
He flew combat missions during the Gulf War, then earned a graduate degree from the US Naval Test Pilot School.
Kelly was working as an instructor pilot at the school when he was chosen to join the astronaut corps in 1996. He has made one previous space flight.
- Flight engineer Lisa Nowak, 43, grew up in Rockville, and attended the US Naval Academy, where she earned a bachelor's degree in aerospace engineering.
She became a naval flight officer, eventually becoming a mission commander. Nowak then attended the Naval Postgraduate School, earning two master's degrees and assignment as an aircraft systems project officer.
Selected as an astronaut in 1996, Nowak, who has three children, has waited 10 years for her first flight.
- Mission specialist Michael Fossum, 48, was born in Sioux Falls, and raised in McAllen, Texas.
A father of four, Fossum worked as a systems engineer at the Johnson Space Centre for five years before he was selected as an astronaut in 1998.
Fossum holds a bachelor's in mechanical engineering from Texas A&M University, a master's in systems engineering from the Air Force Institute of Technology, and another in space science from the University of Houston at Clear Lake.
Fossum, who will be making his first space flight, is one of the Discovery crew's two space-walkers.
- Mission specialist Stephanie Wilson, 39, was born in Boston and attended Harvard, where she earned a bachelor's in engineering science.
Wilson worked on the Titan rocket program in Colorado before attending graduate school at the University of Texas.
After graduating, she went to work for Nasa's Jet Propulsion Laboratory in Pasadena, California, where she was assigned to the Galileo Jupiter probe program.
Selected as an astronaut in 1996, Wilson will be making her first space flight.
- Mission specialist Piers Sellers, 51, is a native of the United Kingdom. He was born in Crowborough, East Sussex, and attended Cranbrook School in Kent.
He studied at the University of Edinburgh in Scotland where he earned a bachelor of science degree in ecological science before moving on to Leeds University, where he got a doctorate in biometeorology.
Recruited by Nasa's Goddard Space Flight Centre in Greenbelt, to do climate modelling, Sellers and his wife moved to the United States in 1982.
Two years later, he began applying to become an astronaut. Sellers became a US citizen in 1991 and finally earned a spot in the astronaut corps in 1996.
A father of two, Sellers has made one previous space flight and is the lead space-walker for this mission.
- Space station crew member Thomas Reiter, 48, was born in Frankfurt in Germany and holds a master's degree in aerospace technology from the Armed Forces University in Germany.
He also attended the Empire Test Pilots' School in Britain. He learned to fly military jets at Sheppard Air Force Base, Texas, then returned to Germany where he helped develop computerised mission planning systems and served as a flight operations officer and deputy squadron commander.
Selected by the European Space Agency in 1992 to become an astronaut, Reiter flew a 179-day European-backed mission aboard the Russian Mir space station from September 1995 through February 1996.
Reiter, who has two sons, will become the first live-aboard member of an International Space Station crew who is neither American nor Russian.
He is scheduled to spend 145 days in orbit and return with a shuttle crew in December.