The weather is looking good for NASA's final planned liftoff of the space shuttle Atlantis on Friday.
Mostly clear skies should greet the seaside launch pad here at Kennedy Space Center for the scheduled 2:20 p.m. ET liftoff. The mission is expected to be the last for Atlantis and one of three final shuttle flights before NASA retires its three-orbiter fleet later this year.
Ground crews plan to begin loading Atlantis' giant orange external fuel tank with its super-chilled liquid hydrogen and liquid oxygen propellants Friday at 4:55 a.m. ET.
"Good news as far as the weather is concerned," STS-132 weather officer Todd McNamara said during a Thursday briefing. "Overall, we're looking at really good conditions for launch operations."
McNamara predicted a 70 percent probability of favorable weather for the launch, with a small chance of low cloud ceilings preventing the shuttle from taking off. NASA needs cloudless skies so that range safety officials have a clear view to watch the entire launch.
Atlantis is slated to carry six astronauts and a new Russian research room called the Mini Research Module 1, or Rassvet ("Dawn"), to the International Space Station. The flight will also deliver a host of supplies and spare parts to help outfit the station for the era after NASA's three-orbiter space shuttle fleet retires. That retirement is currently planned for the end of the year.
In exchange for carrying the Russian module to space on its space shuttle, the United States gets to pack about 3,000 pounds (1,400 kilograms) of cargo inside it for the trip to space. The load will include crew supplies, food, new laptops and new hardware for the station.
"The primary objective is the launching of MRM-1," said Robby Ashley, NASA's STS-132 payload manager. "After the cargo is removed, they will transfer some experiment racks, it will be able to perform science."
As the last planned flight of Atlantis, the upcoming launch will be a momentous occasion, though it's also just business as usual at NASA, mission managers said.
"Every space shuttle flight is an amazing feat," NASA test director Jeremy Graeber said. "There is a huge number of people that are involved and put a whole lot of hard work and heart and effort into it. We care about each one exactly the same."