The United Launch Alliance Delta 2-Heavy rocket, equipped with larger solid-fuel boosters, is still on scheduled to lift off at 11:20 GMT. Forecasters are predicting a 60 percent chance of acceptable weather conditions.
NASA video simulation of DAWN, a robotic mission to explore the main-belt asteroids Vesta and Ceres. It is scheduled to launch September 2007, and arrive at Vesta and Ceres in 2011 and 2015, respectively.