The crew of space shuttle Endeavour's mission STS-134 stand together for pictures after they arrived for launch at the Kennedy Space Center in Cape Canaveral, Florida April 26, 2011. From left are Mission Specialist Greg Chamitoff, Mission Specialist Drew Feustel, Mission Commander Mark Kelly, Pilot Greg H. Johnson, Mission Specialist Mike Fincke and Mission Specialist Roberto Vittori of Italy and the European Space Agency. Launch of Endeavour is scheduled for April 29, with Kelly's wife, US Rep. Gabrielle Giffords, expected to view the launch at the Kennedy Space Center. She was injured in a shooting in Arizona in January. [Photo/Agencies]

CAPE CANAVERAL, Florida - The astronaut husband of wounded Congresswoman Gabrielle Giffords arrived at NASA's launch site Tuesday for this week's flight of space shuttle Endeavour, and said his wife would be following him "pretty soon" - in plenty of time for liftoff.

Endeavour is set to blast off Friday afternoon on its final voyage. It will be the next-to-last space shuttle mission.

Navy Capt. Mark Kelly and his crew flew into Kennedy Space Center early Tuesday afternoon. The countdown began about an hour later.

Speaking on behalf of his five crewmates, Kelly expressed pleasure at seeing the astronauts' wives and children, who flew in a little earlier and gathered nearby.

Giffords was not in the crowd. She has been in Houston, where she is undergoing rehabilitation for a gunshot wound to the head. She was attacked January 8 in her Tucson, Arizona, hometown.

"I'm personally looking forward to my wife, Congresswoman Gabrielle Giffords, getting here pretty soon, to be here in time for our launch on Friday," Kelly told the crowd of family members and journalists.

"It's something she's been looking forward to for a long time," he said. "She's been working really hard to make sure that her doctors would permit her to come. She's more than medically ready to be here, and she's excited about making this trip."

Kelly was joined Tuesday by his identical twin, astronaut Scott Kelly. Both wore turquoise "Gabby" wristbands. Her staff said Giffords' travel for Florida would be provided by NASA.

President Barack Obama and his family also will attend the liftoff.

NASA test director Jeremy Graeber said the presidential visit - and Giffords' presence - will not distract the launch team. It's exciting, though, to have so many people coming for Endeavour's final takeoff, especially first-time guests, he said.

Forecasters put the odds of good launch weather at 80 percent. Launch time is 3:47 p.m. local time.

Endeavour will carry a $2 billion particle physics experiment to the International Space Station along with a load of spare station parts.

The 30-year shuttle program will end this summer with the flight of Atlantis.

This will be the 134th shuttle mission overall and the 25th for NASA's youngest shuttle. It first flew in 1992, as the replacement for the lost Challenger.

"We're going to take Endeavour out for a couple more, probably about 5 or 6 million more miles," Kelly said. It already has logged 116 million miles. "After 25 flights, we will hopefully land here on this runway and then Endeavour is done with its service to the country."

Endeavour will retire to the California Science Center in Los Angeles.