"The system looks good, the weather looks good, and we should be in good shape for launch," Mike Moses, the launch integration manager, told reporters Saturday. "In our minds, we are good to go."
NASA shuttle launch director Michael Leinbach said about 500,000 people are expected to be at the Kennedy Space Center to see the shuttle fire off into space at 8:56 a.m. Monday, CNN reported.
The Orlando Sentinel reported U.S. Rep. Gabrielle Giffords, D-Ariz., who is recovering from a serious gunshot wound to the head, will be among those on hand to watch. Her husband, Navy Capt. Mark Kelly, is the shuttle commander.
NASA weather expert Kathy Winters said there is a 30 percent chance strong crosswinds or low cloud cover could delay the launch. The weather is expected to be less ideal Tuesday, then improve Wednesday, she said.
Endeavour was originally scheduled to have lifted off on its final flight April 29 but a problem with a heater scuttled the launch.
If the mission goes off without a hitch this time, Endeavour would return to Earth June 1.
The shuttle Atlantis is to make its way to the launch pad that same day in advance of the final mission in the space shuttle program's 30-year history.