The Atlantis shuttle was headed for a punctual launch at 2338 GMT Friday, seemingly defying the normal last minute weather and technology hitches that often hold up shuttle blast-offs, according to dpa. The launch comes however after a three-month delay to repair more than 2,000 dents left on the fuel tank by heavy hail in February. Atlantis is headed to the International Space Station with a crew of seven - including one astronaut to relieve Sunita Williams, who will be coming home on the return flight after serving at the station since December. Its main mission is to deliver the next pair of 17.5-ton solar collector panels to be installed during three spacewalks, the first slated for Monday. After heavy thunder storms across Florida in the middle of the week, NASA is expecting an 80-per-cent positive weather prognosis. The launch window extends to June 19. The flight is the first of four shuttle missions this year. The current push is to expand electricity supply at the space station to pave the way for December's installation of the European module Columbus. That will in turn set the stage for installation of Japan's research module, Kibo. The new solar panels are to double power at the station by 2010, when construction on the space station is to be finished. Final occupancy is to be expanded to six instead of just three full time residents.
