Katy Perry is "fascinated" with extraterrestrials.

The pop songstress spends a lot of time reflecting on what lives beyond our galaxy.

Katy grew up in a household with devoutly religious parents where aliens were not regular dinner table discussions.

The star is happy to explore that subject now that she is on her own.

"I'm fascinated by that kind of stuff because of how I grew up, where everything was so black and white," Katy told British newspaper the Sun. "Now I'm seeing a lot more colour in the world and asking more questions. So I'm very into things that are above and beyond me and were before me and will be after me."

Katy's interest in the subject was piqued soon after she was exposed to American TV documentary series Ancient Aliens.

"I've ordered 50 of those DVDs," Katy gushed. "I sent out a Christmas gift basket to people filled with my favourite things and the first season of Ancient Aliens was one of the things I included. It's so good. I made everyone on my tour watch it. I'm just obsessed."

Should aliens ever land on earth, Katy will be prepared for their arrival.

"I do hope that when the aliens come, they'll recognise me. I'll be like, Please don't kill me, I wrote a song called ET," she said..