(AP) -- After enduring a month's delay, seven astronauts boarded space shuttle Endeavour on Sunday for an early evening flight to the international space station.
NASA was hoping thunderstorms would stay away. Forecasters said there was a 70 percent chance the weather would cooperate.
"Look at that!" astronaut David Wolf said, pointing up at the sunshine with both hands.
It was NASA's fourth attempt to send Endeavour on a space station construction mission. Saturday's try was foiled by a series of lightning strikes around the pad that required extra checks of the many critical shuttle systems. Back in June, hydrogen gas leaks held everything up.
No leaks popped up this time, thanks to all of the repairs, as NASA fueled Endeavour's external tank for the planned 7:13 p.m. liftoff. The tight plumbing allowed commander Mark Polansky and his crew to board the shuttle for the first time for a real launch try. None of the previous countdowns got that far.
The astronauts grinned, waved and gave a thumbs-up as they headed to the pad.
Endeavour holds the third and final segment of Japan's enormous $1 billion space station lab, named Kibo, or Hope. It's a porch for experiments that need to be exposed to the vacuum of space. The shuttle also is loaded with large spare parts for the space station and hundreds of pounds of food for the six station residents.
When the shuttle astronauts arrive at the space station, they will make up the biggest crowd ever in a single place in orbit: 13 people.
All of the major space station partners will be represented: the United States, Russia, Canada, Europe and Japan.
An estimated 60 Japanese were on hand for Sunday's launch attempt, a considerably smaller group than back in mid-June for NASA's initial tries.
One of the Americans flying up on Endeavour will trade places with the lone Japanese astronaut on the space station, who has been there since March.
Endeavour will spend nearly two weeks at the space station. In all, the flight will last 16 days. Five spacewalks are planned to hook up the Japanese lab's new porch, replace space station batteries and perform other maintenance.
Eight shuttle flights remain, including this one, all involving space station work.
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