Sarah Brightman is no stranger to the concepts of space and time travel. Her voice, a crystalline soprano that first mesmerized audiences when she originated the role of Christine Daaé in Andrew Lloyd Webber’s “The Phantom of the Opera,” often soars into the stratosphere on albums that bring a pop sensibility to classical music.
Now the English singer is taking her lifelong love of the celestial rather literally. Brightman is in training as a cosmonaut, with hopes of boarding a Russian Soyuz rocket in 2015 for a 10-day journey into space, assuming she passes the final rounds of medical and psychological tests.
Inspired by that possibility, her new album, “Dreamchaser,” gathers an eclectic range of songs whose common theme is expansiveness. She tackles everything from “Ave Maria” to Cocteau Twins, Elbow, and Sigur Rós.
Brightman, who at 53 has been credited as pioneering what we now call the “classical crossover” genre that ushered in artists like Andrea Bocelli, Josh Groban, and Katherine Jenkins, comes to the Boston Opera House on Wednesday. We caught up with Brightman recently by phone.
Q. This new record, with your interpretations of songs by bands such as Sigur Rós and Cocteau Twins, is a nice surprise from you.
A. It was quite a risky thing to do. I think it’s totally important to go where your spirit is leading you. One can continue to do the same kind of things over and over again. This isn’t a huge departure in that it’s still my voice and it has my signature style. My fans have always enjoyed the journeys with me. They kind of expect the unexpected.
Q. How do you describe your taste in music?
A. I have very eclectic taste, and my knowledge of music is pretty broad. But for this record, I was looking for pieces that were space-oriented. I wanted the songs to be expansive and a little off the usual beaten track. The Cocteau Twins song [“Eperdu”] is what I would imagine it’s like when the sun passes the universe, whereas the Sigur Rós piece [“Glósóli”] means “glowing sun.”
Q. Were you already a fan of those bands before making this album?
A. I’ve been a fan of the Cocteau Twins since the ’80s — “Heaven or Las Vegas” and all of that era. And Sigur Rós I’ve been listening to for years. There are loads of repertoire in my music collection. Things come into play at different times because I am an interpreter of music. I always work from themes, and the themes suggest which areas I should listen to.
Q. While it was happening, did you have any idea that you were creating this genre called “classical crossover”?
A. I didn’t really because I’m not calculated in that way. It’s very organic what I do. In hindsight, what happened is, I’ve had a very long career. I came to music when I was really young and have sung in many different genres. When I started doing my solo albums, and projects for other people, all these ingredients came together naturally and I ended up with what they now call “classical crossover.” I still don’t know what that really means.
Q. When you hear your earlier work, especially stuff from “Phantom of the Opera,” how has your relationship with it changed?
A. I love to go see “Phantom,” as few times as I do, and I’ll take a younger relation who hasn’t seen it before but knows I was in it. I get a huge amount of joy seeing them at their age enjoying something that has been around for a long time and I was involved in the whole process of making it. [“Phantom”] is a pretty timeless piece. It’s like a little jewel. So my relationship to it is very fond, very healthy. I always sing a piece from it at my concerts because people love it and I like it. It’s part of my history.
Q. Tell me about the possibility of going to the International Space Station.
A. It’s something I always wanted to do. I was asked if I’d be interested in going up to the space station. I am officially, by the Russian space federation, considered a cosmonaut in training. It’s all been very inspiring for what I do here as an artist.
Q. What’s your notion of what space will be like?
A. I’ve spoken to astronauts and cosmonauts about this, and they all have their own feelings about it. But generally they’re incredibly positive. I want to go into it like a child. I tend not to think too much about it. I want to have no expectations when I get there.
Q. I hear you’d like to record a song from space. Have you decided on one?
A. I have lots of ideas at the moment, but nothing specific.
Q. May I suggest David Bowie’s “Life on Mars”?
A. (Laughs.) Although that is one of my favorite songs, I don’t think I’ll be doing that one.
Q. Barbra Streisand recorded a version of it, so I figured you could, too.
A. I didn’t know she did a version of that.
Q. You’re better off.