Endeavor's liftoff, set for late Wednesday, marks an accelerated pace of launches for NASA.
Wednesday evening's launch of the space shuttle Endeavor marks the onset of a tightly packed set of launches over the next nine months, as NASA pushes to complete the International Space Station and retire the orbiters by 2010.
Barring the unforeseen, a shuttle is slated to leave the launch pad every other month through April. It's an ambitious schedule for the National Aeronautics and Space Administration, which has completed only five missions over the past two years, since resuming flights after the 2003 Columbia tragedy.
Still, the schedule seems tame by pre-Challenger and pre-Columbia standards. After the Challenger disaster in 1986, the National Research Council estimated that NASA could loft 11 to 13 flights a year with a four-orbiter fleet. Three orbiters – the number remaining after Columbia went down – could handle six to eight flights a year.
With five missions between August and the end of April, the shuttle program, like a marathon runner who sees the finish line, is beginning its "kick" to the yellow tape.
"A lot of people said, 'Boy, that's quick,' " said Kim Doering, deputy manager of the space shuttle program during a preflight briefing last month, noting that at the time two orbiters were in the program's processing facility and Endeavor was headed to the pad. Agency officials acknowledge that preparing the shuttles for their missions has been a stretch for workers at the Kennedy Space Center. "But when you look at the rest of the assembly sequence, this is the pace we'll be on," says Ms. Doering.
The seven-member crew for this mission includes Barbara Morgan, a former elementary school teacher who was Christa McAuliffe's backup for the Challenger mission (see story). Then, President Ronald Reagan had outlined a goal of sending private citizens into space aboard the shuttle, beginning with a teacher. After the Challenger disaster, the program was canceled.
In the late 1990s, Sen. John Glenn, a former astronaut, was given a seat. This helped spark a debate about who, outside the usual cast of astronauts, should be allowed aboard shuttle flights. In January 1998, Ms. Morgan became the first member of a new category of educator astronauts. In 2004, three more teachers joined her.