Shuttle Endeavour Blasts Off Toward Space Station

CAPE CANAVERAL, Fla. - The space shuttle Endeavour finally beat the weather late Wednesday as it blasted off on an ambitious, if belated, construction mission to the International Space Station after five frustrating delays.

Running a month late, Endeavour roared into the Florida evening sky at 6:03 p.m. EDT (2203 GMT) from Launch Pad 39A here at the seaside Kennedy Space Center. The orbiter is ferrying seven astronauts, vital spare equipment and a Japanese-built experiment porch to the orbital outpost.

?Persistence pays off, good luck and Godspeed,? NASA launch director Pete Nickolenko told Endeavour?s astronauts just before they successfully launched on the sixth try.

?Endeavour?s patiently waited for this,? replied shuttle commander Mark Polansky.??We?re ready to go and we?re going to take all of you with us on a great mission.?

The shuttle lifted off on the eve of the 40th anniversary of NASA?s Apollo 11 launch, which sent three Americans thundering toward the moon atop a massive Saturn V rocket on July 16, 1969. Apollo 11 astronauts Neil Armstrong and Buzz Aldrin made the first moon landing four days later while crewmate Michael Collins flew overhead in lunar orbit.

The seven astronauts aboard Endeavour are not going quite as far as the Apollo 11 crew. They are headed for the International Space Station about 220 miles (354 km) above Earth to deliver vital spare equipment and a Japanese-built experiment porch to the orbital outpost.

Mission managers cleared Endeavour to fly today after fears surfaced that one of the shuttle's power-generating fuel cells was malfunctioning. A faulty cell is not a risk for launch, but could shorten the planned 16-day mission if it cannot provide power for as long as planned. After subsequent checks suggested the fuel cell was functioning within normal limits, NASA decided to go ahead with launch.

The evening liftoff capped a series of setbacks that had waylaid Endeavour and its crew since mid-June. Lightning and thunderstorms foiled three launch attempts over this last week, while two earlier attempts in June were thwarted by a hydrogen gas leak from a vent pipe on the shuttle's external fuel tank. That glitch was later repaired

Tricky mission at crowded station

Endeavour's crew has an elaborate mission lined up with five spacewalks and complex robotic arm maneuvers to install new hardware on the space station. The shuttle is slated to catch up with the orbital outpost on Friday at 1:55 p.m. EDT (1755 GMT).

"STS-127 to the International Space Station has an array of objectives," Endeavour mission specialist Dave Wolf said in a preflight interview. "It?s heavy on spacewalks and robotics and we?ll be doing a fair amount of re-supply inside the space station, so there?s a broad mix of activities."

In addition to Polansky, pilot Doug Hurley and mission specialists Chris Cassidy - who became the 500th person in space - Julie Payette, Tom Marshburn and Dave Wolf will fly aboard Endeavour. Payette represents the Canadian Space Agency; the rest are NASA astronauts.

Cassidy wore an inside-out baseball cap as a rally hat for good luck before launch, while Payette blew a kiss to cameras before entering Endeavour.

NASA rookie spaceflyer Tim Kopra will also ride the shuttle to the station, where he will replace Japanese astronaut Koichi Wakata as a long-duration flight engineer with the orbiting lab?s six-man Expedition 20 crew. Wakata is due to cap off his station mission and fly home on Endeavour with the STS-127 crew.

When the shuttle arrives at the space station, the outpost will be more crowded than it's ever been, with a record 13 people onboard.

"Everyone knows what it?s like to host your in-laws or other family members and friends over to your home during the holiday season for several days," Thirsk said in a preflight interview. "Everyone loses some personal space; there are some inconveniences; there?s line-ups at the phone; there?s line-ups at the computer; there?s line-ups at the bathroom; and even the preparation of, and the serving of, meals is something that needs to be tightly coordinated. We?re going to experience the same types of things onboard the space station."

A space station porch

Packed into the shuttle's payload bay is an external porch-like facility for the station's $1 billion Japanese Kibo Laboratory. The porch will expose science experiments to the space environment. The new addition will complete the Kibo complex, the largest laboratory on the International Space Station (ISS).

Cassidy described the porch, officially called the Japanese Exposed Facility, as about the size of "four mini-vans."

Endeavour's cargo also includes a cache of other equipment, including spare parts to keep the space station going after the shuttle program retires, planned for 2010.

"STS-127, I like to say, is one of the last major construction missions of the International Space Station," Payette said in a NASA interview. "We?re hoping that in two years from now it will be all complete and fully utilized as a scientific laboratory in space."

When Payette arrives at the station she will reunite with her Canadian colleague Robert Thirsk, who is a month and a half into a long-duration stay on the ISS as an Expedition 20 flight engineer. It will be the first time two Canadians are in space at the same time.

"For a short period of time we'll have two Canadians on orbit, and we are really pleased about that," said Pierre Jean, Canada's space station program manager. "I think it will generate a fair amount of excitement [among Canadians]."

The shuttle crew plans to spend their second day in space conducting a detailed scan of their orbiter's sensitive heat shield for any damage sustained during launch.

Endeavour's flight is NASA's third shuttle mission of 2009, and follows a May mission by the shuttle Atlantis to the Hubble Space Telescope. Today's blast off was the 23rd for Endeavour's and marks the 127th shuttle mission ever. NASA plans to launch seven more shuttle flights by 2010 to complete station construction and then retire its three-orbiter fleet to make way for its replacement, the Orion space capsule and its Ares I booster.

Endeavour and its crew are slated to return to Earth July 31 after completing their mission to the International Space Station.

• New Video - The Kibo Lab: Japan's Hope in Space - Part 1, Part 2
• Final Countdown: A Guide to NASA's Last Space Shuttle Missions
• SPACE.com Special Report - THE MOON: Then, Now, Next

SPACE.com is providing continuous coverage of STS-127 with reporter Clara Moskowitz at Cape Canaveral and senior editor Tariq Malik in New York. Click here for live mission updates and SPACE.com's NASA TV video feed.