The US space shuttle Endeavour began its trek home to Earth Monday after a record five successful spacewalks and 12 days at the International Space Station where astronauts installed Japan's maiden ISS laboratory.
With the installation Japan gained a foothold on the orbital outpost alongside the United States, Russia and Europe, whose laboratory Columbus was delivered to the station in February.
"Endeavour, we have physical separation" of the two crafts, a NASA official said on a live US space agency broadcast of the undocking that took place some 211 miles (340 kilometers) above the Indian Ocean.
Departure of the shuttle and its seven-member crew was delayed 29 minutes to 8:25 pm EDT (0025 GMT Tuesday) following "minor tweaking" to a faulty solar panel latching device, NASA said.
The device, known as a Beta Gimbal Assembly, lets solar wings on the space station tilt along an axis toward the sun to maximize solar energy use, but the assembly on the station's main portside truss did not close correctly and needed to be reset.
After separation, shuttle co-pilot Gregory Johnson took the shuttle on a slow-motion flyaround of the ISS to allow astronauts to document exterior conditions of the station before heading back to Earth.
Endeavour commander Dominic Gorie late Sunday described the 16-day mission as an all-around success.
"We've done awesome," Gorie said.
"Every spacewalk was a win, every robotic op (operation) was a win. We've got a couple more to go with the undocking and the landing, but we've got a great winning team."
The shuttle is scheduled to return to Kennedy Space Center, Florida on Wednesday.
Two astronauts from Endeavour -- mission specialists Robert Behnken and Mike Foreman -- on Sunday attached a 50-foot sensory boom to the outside of the space station.
ISS flight director Dana Weigel said the spacewalk, often referred to by NASA officials as an EVA, or an extra-vehicular activity, had set a new record.
"This was five EVAs, which was more than we've done on any station mission," Weigel said.