CAPE CANAVERAL, Fla - Shuttle Endeavour's most experienced spacewalkers returned to the outside of the International Space Station on Wednesday to extend the reach of the station's robotic crane and bolster the power lines.

"Wow, it's great to be back outside," astronaut Mike Fincke said as he left the space station's airlock shortly before 2 a.m. (0600 GMT) to begin his eighth spacewalk.

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"The most beautiful planet in the universe," he added, admiring the blue Earth 220 miles (355 km) below.

"Nice view, isn't it?" replied lead spacewalker Drew Feustel, making his sixth outing.

The primary goals of the spacewalk, the third of four planned during shuttle Endeavour's mission, is to hook up a fixture so the station's robotic crane can be moved over to the Russian side of the $100 billion complex.

The astronauts also plan to install wiring to give the Russian modules backup access to power from the US solar array wings.

To prepare for the spacewalk, scheduled to last 6 1/2 hours, Feustel and Fincke tried an alternative method for purging nitrogen from their bloodstreams, necessary to prevent the bends.

They spent 50 minutes doing light exercises to speed up their metabolism, which cut the amount of time they needed to breathe pure oxygen before venturing out to work in the vacuum of space. The new protocol also eliminates the need for the spacewalkers to camp out in the reduced pressure environment of the airlock the night before the spacewalk.

The trial run of the new procedure went well, said NASA mission commentator Kyle Herring.

Endeavour and its six-man crew arrived at the station on May 18 for a 12-day servicing call, the next-to-last mission before NASA ends the space shuttle program.

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