Koichi Wakata was still getting used to gravity, though it wasn't going to stop him from diving into a deluge of sushi.

Huge amounts of the delicacy awaited the Japanese astronaut Friday after he returned to Earth aboard shuttle Endeavour with six other astronauts. Wakata, the first Japanese astronaut to return from a long space journey, lived in orbit at the international space station for four and a half months.

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The shuttle and its crew returned after a long but successful construction job that boosted the size and power of the international space station.

Endeavour's smooth and punctual arrival, after more than two weeks in orbit, set off a steady stream of congratulations and an ecstatic welcoming reception for Wakata.

There was more sushi than Wakata had anticipated as Kennedy Space Center workers dropped it off at crew quarters.

Wakata said four hours after touchdown that he had yet to eat any sushi because of all the medical testing. But he was going to splurge as soon as the crew news conference ended.

"I feel great," he told journalists who jammed an auditorium, most of them Japanese. "When the hatch opened, I really smelled the grass of the ground, and just glad to be back home."

The president of the Japanese Space Agency, Keiji Tachikawa, was among the first to greet Wakata and said the astronaut would be accommodated properly when he returns to Japan in a few months.

"He said he did his best," Tachikawa said. The official said he was surprised to see Wakata walking so soon after landing.

The astronauts left behind on the space station said they missed Wakata, even though they were happy with his replacement.

"We certainly miss being there, but there's no place like home," said shuttle commander Mark Polansky. He looked thrilled as he shook hands with senior managers. "What a fantastic mission," he said.

While visiting the space station, Polansky and his crew put on a new addition to Japan's $1 billion lab, installed fresh batteries, and stockpiled some big spare parts. They accomplished all of their major objectives and were part of the biggest gathering ever in space: Counting the six station residents, the crowd totaled 13.

The shuttle flight lasted 16 days and spanned 6.5 million miles (10.5 million kilometers), one of NASA's longest. It wrapped up a 138-day trip for Wakata, who moved into the space station in March. He swapped places with American Timothy Kopra, who rode up on Endeavour.

Before leaving orbit, Wakata said he was yearning for some sushi for his first meal back on the planet and a soak in a hot spring once he's back in Japan. At the top of his list, though, was reuniting with his German wife and their 11-year-old son, who were on hand at the space center for the homecoming. About 50 Japanese, in all, gathered at the landing site.

Wakata made it back just in time for his 46th birthday on Saturday. He said he was looking forward to lots of sushi and good birthday cake, to which Polansky asked, "And you've invited your whole crew, right?"

"Yes — can you handle raw fish?" Wakata said, laughing.

It is Japanese custom to bring souvenirs back from a long trip. When asked by journalists if Wakata did, Tachikawa said the astronaut returned with new ideas and impressions about space.

Endeavour's other astronauts carried out five spacewalks — tying a record for a single flight — and helped their station colleagues when a toilet flooded and an air purifier overheated. The commode, one of three on the linked shuttle and station, was fixed in a day. But the air-cleansing system remained out of order Friday.

Another highlight: The astronauts got to celebrate the 40th anniversary of the first manned moon landing with their own spacewalk.

Japan's Kibo lab — which means Hope — received a front porch for outdoor experiments during Endeavour's visit. An X-ray telescope and space environment monitor were installed on the porch, along with communication equipment.

The mission concluded work on the lab — the largest one at the orbiting outpost — that took more than a year and three shuttle flights. Wakata said seeing Kibo completed was the highlight of his mission.

Next up for the Japanese will be the debut launch in September of an unmanned cargo ship.

As for NASA, seven shuttle flights remain to finish the space station, now 83 percent complete with nearly 700,000 pounds of mass. The next launch, by Discovery, is targeted for the end of August.