At NASA's Kennedy Space Center, the rotating service structure protecting space shuttle Endeavour on Pad A was rolled away in preparation for launch

The U.S. space agency says the countdown is on track for a Friday evening launch of the space shuttle Endeavour to the International Space Station.

NASA officials say all systems are in good shape and that weather conditions for the scheduled launch from the Kennedy Space Center in the U.S. state of Florida are likely to be favorable.  The lift-off is scheduled for 7:55 p.m. EST.

The shuttle will carry seven astronauts and components to increase living space on the space station.

As part of their 15-day mission, the astronauts will deliver two new sleeping units, a bathroom, a kitchenette and exercise equipment.  They will also install a new system to recycle waste-water into safe drinking water.

Endeavour is also delivering a new member of the space station crew.  American Sandra Magnus will replace U.S. astronaut Gregory Chamitoff.

Spacewalks are also scheduled during the mission to repair a broken solar panel array on the space station.  The array has not been rotating properly because its joint is clogged with metal shavings.

The Endeavour mission is the last U.S. shuttle flight scheduled for this year.  A mission scheduled for last month to conduct repairs on the Hubble Space Telescope has been postponed until May 2009. Endeavour is scheduled to return to Earth on November 29.

NASA plans to retire the shuttle fleet in 2010.

Some information for this report was provided by AFP, AP and Reuters.