NASA ready to launch Atlantis, ending space hiatus

CAPE CANAVERAL, Fla. -- After weeks of fuel line repairs, NASA's space shuttle is poised to end a three-month launch hiatus with today's planned liftoff to the international space station.

Six astronauts are set to ride to orbit aboard shuttle Atlantis at 3:46 p.m. Their primary mission: Install a key truss that will help form the backbone needed to support future power-producing solar arrays on the station. The planned 11-day flight will be the first for the shuttle since June, when sister ship Endeavour visited the outpost to drop off three new residents.

"This is the first time we have ever attached two truss segments together," said Bill Gerstenmaier, the space station program manager. "It's extremely complex and made even more difficult by doing it in space."

Video of launch

The shuttle's eight-and-a-half-minute trip to orbit will feature yet another first.

When Atlantis lifts off, television viewers can expect to see some stunning video of the launch from a camera NASA has mounted near the top of the shuttle's external fuel tank. The $760,000 camera will look down on Atlantis as the shuttle hurtles toward space and record, among other things, the separation of the ship's two booster rockets about two minutes into flight.

The show will end when Atlantis reaches orbit and jettisons the external tank.

"We think that by flying this camera we'll get some engineering data that will help us," said Ron Dittemore, the shuttle program manager. "A secondary benefit is that you get to fly along with the crew. You're going to have a birds-eye view of what it looks like to be on top of the tank looking back down at the ground as you take off and press on to orbit."

Good weather predicted

Forecasters are predicting an 80 percent chance of favorable weather at Kennedy Space Center for Monday's launch, with a chance of storm clouds being the major concern. Conditions also look good at Johnson Space Center in Houston, home of the shuttle's Mission Control Center. Shuttle managers postponed a scheduled launch attempt last Wednesday when Hurricane Lili threatened Texas' Gulf Coast. It marked the first time in shuttle history that a flight was delayed because of the forecast in Houston.

Engineers still were analyzing two technical worries on Sunday, however, that must be dealt with before Atlantis will fly.

A heater is malfunctioning in one of three lines that remove excess water from the shuttle's electricity-producing fuel cells. The heater is used to keep ice from blocking the line. Under a worst case scenario involving additional failures, backed-up water could kill the shuttle's electrical power.

There also are concerns that oil from ground support systems might have accidentally contaminated Atlantis after a 2001 landing at Edwards Air Force Base in California. Mission managers were optimistic both issues would be resolved during a 5:45. a.m. meeting Monday that will address whether to fuel the shuttle for flight.