space shuttle Atlantis prepared to descend back to Earth Wednesday, leaving the way clear just in time for US Navy ships to aim missiles at a rogue satellite, the weather was forecast to be fine for the landing of the Atlantis and its seven crew members scheduled at 9:07 am at the Kennedy Space Center here, the National Aeronautics and Space Administration said.

"I'm really optimistic looking at the weather briefs, that things are going to play out really well for Kennedy," flight director Brian Lunney told reporters Tuesday, NASA wants to land the shuttle before the Navy attempts to fire missiles at an out-of-control spy satellite hurtling to Earth, which could come as early as later Wednesday, in the Pacific, But Lunney said there was no sense of pressure to land in a hurry, "I'm not going to land the vehicle until it's safe to do so," he told reporters, "Touchdown of the Atlantis opens the window of opportunity for the US military to shoot down that rapidly decaying US intelligence satellite," said Geoff Morrell, the Pentagon press secretary, on Tuesday.

"There is a very low risk because our orbits are quite different," Atlantis Commander Steve Frick said. "The satellite is well below us (where) we are now, but of course we are going to land before they break up that satellite."

Atlantis is returning from a two-week mission during which the crew installed a European laboratory at the orbiting International Space Station, frick will fire up Atlantis' engines for two and a half minutes to slow it down as it surges Earthward at up to 25 times the speed of sound, atlantis will then glide for an hour, flying over the Gulf of Mexico and past western Cuba before touching down at Kennedy, near Cape Canaveral, Florida.

If conditions prevent landing during the first window of opportunity, there will be another 90 minutes later. Failing that, Atlantis can try landing at Edwards Air Force base in California , the shuttle must land by Friday, when its hydrogen batteries will run out, on Tuesday the astronauts on board were preparing for their return to Earth, after separating from the space station early Monday, NASA said.