Katy Perry has been texting Buzz Aldrin in preparation for her space-themed MTV Video Music Awards (VMAs) performance.

Katy Perry

Katy Perry

The 'Swish Swish' singer will host this year's show on August 27 and has been picking the brains of the 87-year-old astronaut, who was one of the first men to walk on the moon with Neil Armstrong on the Apollo 11 mission in 1969, and American astrophysicist Neil deGrasse Tyson.

She revealed on Twitter: "I've been training with MTV in zero gravity, eating astronaut ice cream, and I'm on a group text with Buzz Aldrin and Neil deGrasse Tyson."

Katy previously teased her appearance will be out of this world in a video in which she is dressed in a space suit floating through the universe.

Taking to Instagram, the video featured the line "This August, History will be eclipsed" and she captioned the promo: "Introducing your MOONWOMAN. Brace for impact! August 27th on # MTV # VMAs.(sic)"

The nominations for the VMAs were revealed earlier this week, and Kendrick Lamar scored the most nods with eight, for Video of the Year, Best Hip Hop Video, Best Cinematography, Best Direction, Best Art Direction, Best Visual Effects, and Best Choreography for the video for his hit single 'Humble', whilst the musician himself is also up for Artist of the Year.

And he faces a lot of competition from both Katy and The Weeknd, who are the second-most nominated acts with five.

The 'Reminder' hitmaker will face Kendrick in the race for Video of the Year, Artist of the Year, Best Direction and Best Art Direction, whilst also being nominated for Best Editing.

Meanwhile, Katy's single 'Chained To The Rhythm' is nominated for Best Pop Video, Best Direction and Best Visual Effects, whilst her track 'Bon Appetite' is up for Best Art Direction.