By Irene Brown in Florida

It was not exactly the view he was hoping for, but British-born astronaut Piers Sellers did manage to spot his homeland while he was working outside the space station at the weekend.

You become very, very aware of how huge the planet is below you and how beautiful it is

Piers Sellers

"It was plainly marked by a continuous layer of white clouds," said Dr Sellers, during a crew news conference on Sunday.

"The only way I could find it was by all the jet contrails leading into Heathrow and Gatwick that made a big cross over the middle of the British Isles - so that's how I knew somewhere down there was London."

Dr Sellers and colleague David Wolf are scheduled to make a third and final spacewalk on Monday to complete installation and setup of a new 13-metre-long (45 feet) solar array truss on the International Space Station.

Big and beautiful

Little can rival the experience Dr Sellers had while working at the end of the beam on Saturday, however.

"I was hanging out on the truss by one hand for a while," Dr Sellers recalled. "It was night and suddenly I saw the Sun come up on the horizon. All I could see was the shuttle ahead of me and my feet hanging over the Earth.

The two astronauts have a final walk to complete

"I watched the dawn come up over the planet, just come in a line straight underneath me and pass underneath me and then the sun came up and hit me in the face. It's obviously the most beautiful thing I've ever seen."

"When you're hanging there... just holding on by your fingers, you're not aware that you are wearing a spacesuit.

"It's just like you're standing in space naked... in a totally new environment. It was an amazing feeling," he added.

"You become very, very aware of how huge the planet is below you and how beautiful it is."

Changing tastes

Sellers and Wolf are part of a six-member shuttle crew that is wrapping up a week-long stay at the space station. In addition to the new truss, the astronauts have delivered science experiments, clothing, equipment and food for the live-aboard station crew.

US space agency astronaut Peggy Whitson and her two Russian cosmonauts have been in space for 131 days and are scheduled to remain aboard the outpost for about another month.

Fortified by the shuttle crew's delivery of salsa, Dr Whitson said she was in no hurry to get home.

"We choose our meals based on what goes well with salsa," she added. "We could probably eat paper if we had it with salsa."

Being in space has affected her sense of taste. Dr Whitson said she just could not stand what used to be one of her favourite foods on Earth - shrimp.

And she has found it rather odd that she now has calluses on the tops of her feet (from using foot restraints) rather than on the bottoms.

Popstar's omission

Aside from missing her husband and friends, Dr Whitson said she was having a great time in space.

"As long as I am busy, I'm quite happy to stay," she said.

"It's hard for me to imagine actually being back home," she added, "because I guess I feel like this is my home right now."

Dr Whitson and her crewmates will not have much time to recover from the shuttle astronauts' departure before their next guests arrive: two cosmonauts and a Belgian astronaut who will be ferrying a new Soyuz "lifeboat" to the station.

The crew, which at one time had been expected to include pop singer Lance Bass, is scheduled to stay about a week before returning home in the station's old Soyuz.

The Russian Space Agency plans to fly cosmonaut Yuri Lonchakov in place of the ballast officials initially said would be flown in the popstar's place. Bass was pulled from the flight when his backers failed to make payments as promised on the $20m fee.

The shuttle is scheduled to depart the station on Wednesday and return to the Kennedy Space Center in Florida on Friday.