Soprano superstar Sarah Brightman has confirmed that she's planning a flight to the International Space Station and hopes to sing a song in orbit — but not until after she finishes up the worldwide concert tour that she's just about to start.

We've basically known about Brightman's spaceflight gig since August, but today's news conference in Moscow gave the British singer a chance to talk about the multimillion-dollar orbital tour. She told reporters that she's had an "incredible desire" to go into outer space since childhood. In fact, seeing the Apollo 11 moon landing in 1969 "actually inspired me and gave me the courage to go into the career that I have," the 52-year-old said.

Brightman started out as a disco singer in the late '70s with spacey tunes such as "I Lost My Heart to a Starship Trooper" and "Love in a UFO," but she really made her mark in the Andrew Lloyd Webber musicals "Cats" and "Phantom of the Opera." She was even married to the impresario for a time. Since then, she's had a successful solo career, specializing in the classical crossover genre.

Today's briefing put heavy emphasis on the "Dreamchaser" album and concert tour that's scheduled to hit early next year, as well as Brightman's role as a UNESCO Artist for Peace ambassador.

"I don't think of myself as a dreamer — rather, I am a dream chaser," Brightman said. "I hope that I can encourage others to take inspiration from my journey both to chase down their own dreams and to help fulfill the important UNESCO mandate to promote peace and sustainable development on Earth and from space. I am determined that this journey can reach out to be a force for good, a catalyst for some of the dreams and aims of others that resonate with me."

SarahBrightman.com via YouTube

Singer Sarah Brightman gives a thumbs-up sign during one of her medical tests in Russia, conducted in preparation for spaceflight.

She emphasized that although she's received medical approval from the Russians for a flight aboard a Soyuz craft to the space station, she won't be able to follow through with the six-month spaceflight training course at Russia's Star City facility until after the 2013 concert tour is over.

SpaceAdventures / SarahBrightman.com

Singer Sarah Brightman is about to embark on a "Dreamchaser" concert tour.

She's got plenty of time: Brightman probably won't be able to catch a ride to the station until 2015, when the space station's partners are planning to have astronauts begin a yearlong stay in orbit. Because of the logistics for that extended mission, there'll be an extra seat on an outbound and inbound Soyuz that a paying passenger can fill.

Like the eight other private space tours that have gone to the station over the past 11 years, Brightman's 10-day space odyssey is being arranged through Virginia-based Space Adventures. (One space traveler, software billionaire Charles Simonyi, has gone twice — which would make Brightman the eighth paying guest to visit the space station. She's the second woman to do so, after Iranian-American entrepreneur Anousheh Ansari.)

Space Adventures' chairman, Eric Anderson, said the financial arrangements for the tour were confidential. However, the going rate for trips to the space station has risen to roughly $50 million. Considering that Brightman's net worth has been estimated at less than that, it's possible that at least part of the fare is being paid by her promoters.

Brightman also has purchased a seat on Virgin Galactic's suborbital SpaceShipTwo rocket plane, at a cost of $200,000, and she's supporting a science-themed Galactic Unite Brightman scholarship program as well. SpaceShipTwo is expected to begin commercial service in the 2013-2014 time frame. 

In the months ahead, Brightman said she would work with UNESCO to develop a program to promote the conservation of Earth's resources, as well as education for girls in science and engineering. She said she expected there would be a "chain of events" tying in to the program, including concerts, multimedia experiences and a "song from space."

Space Adventures said she would continue her U.N. work after the space mission, through a series of "Space to Place"concerts at UNESCO World Heritage Sites, biosphere reserves and parks. 

UNESCO's director of public information, Neil Ford, was on hand in Moscow to provide backup for the singer. "How amazing that you're about to realize your own dream and fly into space," he told Brightman. Ford said one of UNESCO's goals for the project was to put "science to use for human ingenuity."

Anderson said Brightman was an attractive candidate for a space station trip in part because of her high profile as the world's best-selling soprano. "I can think of no better ambassador for the idea of human spaceflight," he said.

Based on Brightman's comments during the question-and-answer session, it could be an entertaining ride. One journalist, for example, asked whether she was concerned about encountering aliens during the trip. "I'd love to be kidnapped by an alien," Brightman quipped. And when a reference was made to "The Fifth Element," a movie in which the French actress Maiwenn played an alien diva, Brightman answered, "I probably am similar to the diva — without all the tentacles she had."

More music from space:

• A heroic flute duet from orbit
• Listen to the first song from Mars
• Scientists use real stars for reggae
• U2 concert adds a surprise from space

For more information about singer Sarah Brightman's space adventure, check out SarahBrightman.com.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.