NASA pressed ahead with Thursday's planned launch of shuttle Atlantis, even though bad weather threatened to delay the mission to add another science lab to the international space station. Forecasters said there was a 70 percent chance that rain, clouds and possibly even a severe thunderstorm would keep Atlantis on the pad for yet another day. The space shuttle is already two months late in delivering the European lab, Columbus, to the space station

Faulty fuel gauges grounded Atlantis in December. Engineers worked round the clock and through the holidays to fix the problem, which turned out to be a bad connector in the external fuel tank. Although confident of the repair, NASA officials acknowledged they would be monitoring Atlantis' fuel gauges with more interest than usual, once fueling got under way.

NASA said at least three of the four fuel gauges must work properly once Atlantis' tank is filled in order for the launch to proceed. The gauges are part of a critical safety system to help ensure that the main engines do not run on an unexpectedly empty tank during the 8 1/2-minute climb to orbit. They have performed erratically during countdowns for nearly three years and postponed several launches. Columbus - a US$2 billion (EUR 1.4 billion) high-tech laboratory is the European Space Agency's primary contribution to the space station. In the making for 23 years, the lab has endured station redesigns and slowdowns, as well as a number of shuttle postponements and two shuttle accidents.