More than half of the teachers who competed with Christa McAuliffe to fly in the doomed space shuttle Challenger two decades ago were to watch Wednesday as Endeavour lifted off with NASA's first educator-astronaut aboard.
Former schoolteacher Barbara Morgan, who was McAuliffe's backup, will be seated on the lower deck in the middle, exactly where McAuliffe sat 21 years ago.
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"I think the great thing about it is that people will be thinking about Challenger and thinking about all the hard work lots of folks over many years have done to continue their mission," Morgan said last month.
Endeavour, the space shuttle that was built to replace the Challenger, was to blast off Wednesday evening on a two-week trip to the international space station.
Seven astronauts are assigned to the mission, including a Canadian doctor, a chemist who knows sign language and is a former competitive sprinter and long jumper, and a commander whose identical twin brother is also a shuttle pilot.
But the spotlight is on Morgan.
First lady Laura Bush called Morgan on Tuesday and congratulated her from one schoolteacher to another. She told her teachers and students will be watching her mission with pride.
On hand at Kennedy Space Center will be more than half the 114 Teacher-in-Space nominees from 1985 and two of NASA's three other teacher-astronauts who were chosen in 2004.
They'll be joined by many of the participants from an education conference that centered on Morgan's flight. The conference in nearby Orlando concluded Tuesday, Endeavour's original liftoff date, but most of the about 400 attendees are expected to stay for the launch. The one-day delay was caused by a leak in the shuttle crew cabin that needed to be plugged.
The families of the lost Challenger astronauts also were invited for liftoff. At least one will be represented. June Scobee Rodgers, whose husband was Challenger's commander, will attend on behalf of the Challenger Center for Space Science Education, which she helped to establish following the 1986 accident.
Morgan, 55, a former Idaho elementary school teacher who's spent nearly the past decade in astronaut training, will operate Endeavour's robot arm and oversee the transfer of cargo from the shuttle into the station. Those are her main jobs, given all the station construction work and repairs that need to be done on this mission.
But she'll make time to speak with schoolchildren from orbit. Six hours have been set aside exclusively for education. She's also taking up 10 million basil seeds that will be distributed to teachers and schoolchildren to grow in space-style chambers.
NASA hopes Morgan's mission will inspire youngsters to pursue science, math and engineering careers.
"Our call to action at NASA is to encourage the next generation of explorers," said Joyce Leavitt Winterton, NASA's assistant administrator for education. She called space "the ultimate classroom" on Tuesday and said McAuliffe would be on her mind — and many educators' minds — throughout the mission.
Morgan sees her role in the flight as a continuation, rather than a completion, of McAuliffe's unfinished work and snuffed-out dream. And she sees this mission, in particular, as a tribute to the Challenger crew.
McAuliffe and six others were killed Jan. 28, 1986, when Challenger exploded barely a minute after liftoff. Morgan was watching from the press site, just three miles from the launch pad.
She eventually returned to her teaching job in McCall, Idaho, but continued to speak publicly on NASA's behalf. In 1998, Morgan was presented as NASA's first educator-astronaut, a teacher who would train to fly in space as a full-fledged astronaut rather than simply a guest teacher.
On Feb. 1, 2003, Morgan was in NASA's shuttle training aircraft flying over the landing strip, with the chief astronaut at the controls. They were awaiting the arrival of Columbia, which was supposed to carry Morgan into orbit that fall.
Again, tragedy struck and Morgan was confronted with another lengthy wait.
"That's what defines teachers is perseverance and patience," she explained, patiently, when asked by yet another reporter about her two decades of sticking by NASA.
Since she was named McAuliffe's backup in 1985, Morgan and her author husband, Clay Morgan, have had two sons. She said all three have supported her dedication to NASA and share her belief in the space program.
She's said repeatedly she doesn't expect to be afraid on launch day, just really, really alert.
Crewmate Tracy Caldwell plans to "squeeze the life out of her" when they reach orbit. Alvin Drew, who will be seated next to Morgan, will offer high-fives all around.
As for Morgan, she expects to let loose a loud "Woo-hoo!"