The National Aeronautics and Space Administration has declared that all launches for the foreseeable future will happen in daylight, so that cameras can film the shuttle as it streaks into orbit and record any debris that might damage the orbiter.
The agency is adding more cameras and converting others to digital to ensure clear images of the external fuel tank, the source of an estimated 1.67-pound chunk of foam that flew off the shuttle Columbia and smashed into the left wing.
Investigators think the foam did enough damage to the wing to allow superhot gases to get in during re-entry, which destroyed the shuttle and killed its crew Feb. 1.
The daylight mandate dramatically reduces the number of days NASA can launch, said Greg Oliver, chief of the shuttle program's ascent/descent branch at Johnson Space Center. When combined with other conditions that dictate when a shuttle headed for the international space station can launch, he said, the opportunities are further curtailed.
Throughout next spring and summer, there are roughly monthlong blocks in which all of the conditions can be met. But after early October, there are only a handful of days in November and January -- and none in December, February or early March -- when a shuttle could fly.
"In the November-to-January time frame, we're talking about maybe three tosix days available to us," Oliver said.
Shuttle missions are already famously complicated to schedule and launch, with weather, technical glitches and myriad other factors playing a role. Launching to the space station is even more complex.
For starters, because of the orbit of the station and the rotation of the Earth, NASA can carve out only one, five-minute launch window each day to get to the orbiting laboratory from Kennedy Space Center. That's one reason that six of the 16 launches to the space station have occurred at night.
In addition, the "beta angle" -- the angle between the sun and the plane of the station's orbit -- must be factored in, to avoid exposing the orbiter to too much sunshine -- and too much heat -- while it is docked at the station.
John Shannon, the shuttle program's flight operations and integration manager, said it's uncertain just how the constraints will affect the station, which has relied on the shuttle to both bring new components into space and ferry crews back and forth.
He said the restrictions will not translate into the kind of schedule pressure that accident investigators said might have contributed to the Columbia disaster.
But NASA managers must be vigilant to make sure that doesn't happen, Shannon said.
"We have to guard against that," Shannon said. "Everybody who's worked here for a long time looks at that thing [blackout chart] and says, 'Wow, we need to get something going here and here and here.' And you say, 'No, we are not going to do that. That is not the way we're going to operate.' "
Shuttle-program managers still have almost no idea when they will be able to launch. Work is continuing on the recommendations made by the Columbia Accident Investigation Board, including redesigning parts of the external tank and developing a way to repair the shuttle's thermal-protection system.
But they do know that the first flight back -- and possibly a second -- will be largely a test flight. Paul Hill, lead flight director for the next mission, said astronauts will try out the method for inspecting the thermal tiles and reinforced carbon-carbon panels that protect the orbiter from the heat of re-entry. An entire spacewalk will also be devoted to testing the proposed method of repairing the tiles in orbit.
Gwyneth K. Shaw can be reached at email@example.com or 202-824-8229. Michael Cabbage can be reached at firstname.lastname@example.org or 321-639-0522.