florida, April 1 -- Nasa began the countdown on Monday for humanity's first launch to the moon in 53 years. The 32-storey Space Launch System rocket is poised to blast off on Wednesday at 6:24pm (2224 GMT), with four astronauts. After a day in orbit around Earth, their Orion capsule will propel them to the moon and back. There are no stops - just a quick U-turn around the moon. The nearly 10-day flight will end with a splashdown in the Pacific. "Our team has worked extremely hard to get us to this moment," said launch director Charlie Blackwell-Thompson. "Certainly all indications are right now we are in excellent, excellent shape." Managers said the rocket is doing well following the latest round of repairs. Forecasters said the weather sh...