Saturday, August 8, 2009

Completing Kibo: STS-127 Marks New Era for Science

Saturday, August 8, 2009
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For the multinational crew of seven astronauts aboard space shuttle Endeavour, the STS-127 mission to the International Space Station was a resounding success. Lasting nearly 16 days, the flight was one of the longest of NASA's Space Shuttle Program. The team's main goals -- completing assembly of Japan's Kibo laboratory complex and delivering spare station parts for future use -- called for five spacewalks and intricate robotics work by the shuttle and station crews.

But the first challenge was getting off the ground. A gaseous hydrogen leak halted two launch countdowns -- and once the leak was repaired, weather problems halted more attempts. Finally, Endeavour and crew enjoyed a picture-perfect launch at 6:03 p.m. EDT on July 15, rocketing away from NASA's Kennedy Space Center in Florida just one day before the 40th anniversary of the launch of Apollo 11, humanity's first visit to the moon.

Commanded by veteran astronaut Mark Polansky, the STS-127 crew also comprised Pilot Doug Hurley, Mission Specialists Dave Wolf, Christopher Cassidy, Julie Payette of the Canadian Space Agency, Tom Marshburn and Tim Kopra. Upon Endeavour's arrival at the station, Kopra replaced the Japan Aerospace Exploration Agency's Koichi Wakata as the Expedition 20 flight engineer.

After a day in orbit spent checking out the shuttle's heat shield, Polansky guided Endeavour to a link-up with the International Space Station at 1:47 p.m. July 17 as the two vehicles glided 220 miles above the north coast of Australia. Once the hatches were opened, Wakata and Kopra swapped seat liners, officially making Kopra a member of the Expedition 20 crew.

The combined crews of Endeavour and station added up to 13 people -- the most humans ever in orbit at the same place at the same time.

With both spacecraft and astronaut teams together in space, it was time to get to work.

The mission's main objective was to install the Japanese Experiment Module-Exposed Facility, the final piece of the Kibo laboratory. The Exposed Facility will serve as a permanent "porch" aboard the station, allowing experiments to be exposed to the space environment. On Flight Day 4, spacewalkers Wolf and Kopra spent five-and-a-half hours outside the orbiting outpost, preparing the attach points on both the Kibo hardware already in place and the new component to be installed. The porch then was installed by Polansky and Payette at the controls of Endeavour's robotic arm, and Hurley and Wakata controlling the station's robotic arm. Additionally, Kibo's robotic arm provided a view of the installation.

Endeavour also brought up the Japanese Experiment Logistics Module-Exposed Section, a payload carrier that temporarily attached to the Exposed Facility. Three days after the astronauts installed the facility, the carrier was robotically plucked from Endeavour's payload bay and handed off to the station arm, which repositioned it near the Kibo complex. During another spacewalk, Wolf and Cassidy readied the carrier and the facility for attachment. On Flight Day 9, the Kibo robotic arm made its operational debut with Wakata at the controls as he moved three experiments from the carrier to the facility. The carrier was returned to the shuttle's payload bay three days later.

Spacewalkers Marshburn and Cassidy also installed video cameras on the Exposed Facility, which will help provide a view of the H-II Transfer Vehicle, or HTV, scheduled to arrive at the station this fall.

In addition to the astronauts' hard work to complete Kibo, they also needed to install several space station components for future use. As with their Kibo efforts, this process took several days, multiple spacewalks and plenty of robotics work to accomplish.

STS-127 Spacewalks:

First Spacewalk: Wolf and Kopra prepared the Kibo laboratory and the Exposed Facility for installation and deployed a cargo carrier attachment system on the P3 truss that failed to unfurl in March. Spacewalk time: five hours, 32 minutes.

Second Spacewalk: Wolf and Marshburn installed the space-to-ground antenna, pump module and linear drive unit to a stowage platform on the P3 truss. Spacewalk time: six hours, 53 minutes.

Third Spacewalk: Wolf and Cassidy prepared the Exposed Section payloads for transfer to the Exposed Facility and replaced two station batteries before ending the spacewalk early due to a problem with Cassidy's suit. Spacewalk time: five hours, 59 minutes.

Fourth Spacewalk: Cassidy and Marshburn replaced the remaining four station batteries. Spacewalk time: seven hours, 12 minutes.

Fifth Spacewalk: Cassidy and Marshburn installed video cameras on the Exposed Facility and completed other miscellaneous tasks around the station. Spacewalk time: four hours, 54 minutes.

During the mission's third spacewalk, Wolf and Cassidy began the task of replacing six batteries that power the station's P6 truss in the absence of sunlight. They swapped out two batteries before a potential problem arose with the carbon dioxide scrubber in Cassidy's spacesuit. Although Cassidy was never in danger, mission rules called for an early end to their excursion. The remaining four batteries were replaced by Cassidy and Marshburn two days later.

Other spares transferred to the station for long-term storage were a pump module, space-to-ground antenna and a linear drive unit.

With several days of intense work and accomplishments behind them, the shuttle and station crews said their farewells, and Endeavour pulled away from the station July 28 after 11 days of docked operations.

Before coming home, the crew of Endeavour deployed two pairs of satellites: the Dual RT Astrodynamic GPS Orbital Navigator Satellite, or DRAGONSat, and the Atmospheric Neutral Density Experiment-2, or ANDE-2. DRAGONSat's two satellites will test the ability of two spacecraft to rendezvous based on data provided by the Global Positioning System, and ANDE-2 will study the atmosphere at an Earth altitude of 200 miles.

Landing day dawned bright and sunny at Kennedy Space Center. After 248 orbits and more than 6.5 million miles, Endeavour and crew touched down on Runway 15 at Kennedy's Shuttle Landing Facility at 10:48 a.m., landing right on time at the first opportunity and bringing Wakata home to Earth after 138 days in space.

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