LONDON — British soprano Sarah Brightman is aiming to perform where no professional singer has ever gone before: the International Space Station.

The 54-year-old said Tuesday she is working with composer Andrew Lloyd Webber, her ex-husband, to create a song she will sing in space after she blasts off Sept. 1 in a Russian Soyuz rocket.

Brightman, known to many for her role years ago in the musical "The Phantom of the Opera" and for a duet with tenor Andrea Bocelli, told reporters she felt "overwhelmed" and excited — but not yet nervous — as she prepares for her trip.

"I would like to sing something from space," she said. "We're trying to work out all the technical details, obviously it's quite a complex thing to do."

She said she and Lloyd Webber are working to find a song that "suits the idea of space" while scientists iron out how to make the performance work, possibly with a choir or another singer on Earth.

"I'm trying to find a piece which is beautiful and simple in its message, as well as not too complicated to sing," she said.

Brightman would not disclose the cost of the trip — reportedly 35 million pounds ($52.8 million) — but maintained she is paying for it herself. She played the original lead in "Phantom," was an original cast member in "Cats," and has sold 30 million records worldwide.

On the journey, arranged by the private space company Space Adventures, the singer will be part of a three-person team and spend 10 days aboard the space station.

She began training in January at Star City near Moscow, spending hours every day learning Russian, becoming familiar with all the space equipment and training in high g-force launch simulators.

"It feels like you've got an elephant on your chest, that's the only way I can explain it when you're in centrifuge," she said.

Brightman said she has wanted to go into space since she watched the first moon landing in 1969 as a 9-year-old.

"For me to have got this far and have a taste of what I felt at that time, to be part of the future, is an amazing thing," she said.