There were five Americans, one Indian immigrant and one Israeli (that country's first astronaut) aboard the Columbia.
Commander Rick Husband (45) was an Air Force colonel from Amarillo, Texas. The former test pilot, who worked with the RAF in the 1980s as an exchange pilot, was selected as an astronaut in 1994 on his fourth attempt. "It's been pretty much a lifelong dream and just a thrill to be able to get to actually live it out," the married father of two said in an interview before the launch of Columbia, his second spaceflight.
Pilot William McCool (41) was a US Navy commander who grew up in Lubbock, Texas. He graduated second in his class of 1983 at the Naval Academy, went on to test pilot school and became an astronaut in 1996. This was his first space flight. He was married with three sons, ages 22, 19 and 14.
Payload Commander Michael Anderson (43) was the son of an Air Force man and grew up on military bases. He was flying for the US Air Force when NASA chose him in 1994 as one of only a handful of black astronauts. He travelled to Russia's Mir space station in 1998.
The lieutenant colonel, who lived in Spokane, Washington, was in charge of Columbia's dozens of science experiments.
Kalpana Chawla (41) emigrated to the US from India in the 1980s and became an astronaut in 1994. At the time, she wanted to design aircraft and the space programme was the furthest thing from her mind.
"That would be too far-fetched," the engineer had said. But "one thing led to another" and she was chosen as an astronaut after working at NASA's Ames Research Centre and Overset Methods Incorporated in Northern California.
Ms Chawla was a heroine in India. One Indian news agency even tracked Columbia's flight so it could tell readers the exact minute they could wave to the skies to hail their countrywoman.
On her only other spaceflight, in 1997, she made mistakes that sent a science satellite tumbling out of control. Other astronauts had to go on a spacewalk to recapture it.
Ilan Ramon (48) was a colonel in Israel's air force and the first Israeli in space. His mother and grandmother survived the Auschwitz death camp, and his father fought for Israel's statehood. He himself fought in the Yom Kippur war in 1973 and the Lebanon war in 1982. He served as a fighter pilot in the 1970s, 1980s and early 1990s, flying F-16s and F-4s. He was chosen as Israel's first astronaut in 1997, then moved to Houston the next year to train for the shuttle flight. His wife, Rona, and their four children, aged five to 15, live in Tel Aviv.
David Brown (46) was a US Navy captain, pilot and doctor. He joined the Navy after a medical internship, then went on to fly the A-6E Intruder and F-18.
He became an astronaut in 1996. Columbia's mission was his first spaceflight.
Laurel Clark (41) was a diving medical officer aboard submarines and then a flight surgeon before she became an astronaut in 1996. She had been on board Columbia to help with science experiments. She lived in Racine, Wisconsin, and was married with an eight-year-old son.