In a historic first, Russia is set to launch an actor and a film director into space to make a feature film in orbit – a project the nation's space chief has hailed as a chance to raise the prestige of Russia's space program.

Actor Yulia Peresild and director Klim Shipenko are set to blast off Tuesday for the International Space Station in a Russian Soyuz spacecraft together with cosmonaut Anton Shkaplerov, a veteran of three space missions. After 12 days on the space outpost, Peresild and Shipenko will return to Earth with another Russian cosmonaut.

The crew plans to film segments of a new movie titled "Challenge" about a surgeon summoned to rush to the space station to save a crew member who suffers a heart condition.

Speaking at a news conference at the Russian launch facility in Baikonur, Kazakhstan, Peresild acknowledged that the training for the mission was grueling but described it as a once-in-a-lifetime opportunity.

"It's a miracle, an incredible chance," she said. 

"We worked really hard and we are really tired, even though we stay in good spirits and smile," the 37-year-old actor confided. "It was psychologically, physically and morally hard. But I think that once we achieve the goal, all that will seem not so difficult and we will remember it with a smile."

Peresild said it was difficult for her to adapt to the strict discipline and rigorous demands required during the training. 

"Here on Baikonur, we made friends with everyone and all people warmed up," she said. "But it was quite difficult in the beginning, when you aren't given much choice: Just go, run, go faster, hold on, carry on. It wasn't easy for us and it was quite unexpected, but we have gone through it."

She said learning about the design and handling of the spacecraft was the most challenging part of the preparation for the flight. 

"It didn't come easy for me, to be honest," she said. "For the first two weeks, I was learning it until 4 in the morning every night. There are so many acronyms, and if you don't learn them all you won't understand anything else further on."

The part of the training that Peresild liked the most was a flight imitating weightlessness, in which a plane goes into a steep dive to allow those inside about 20 seconds in zero gravity. She added that she realizes that zero gravity in orbit could be completely different and is gearing up for her first morning in orbit. 

"Some mornings could be difficult, even on Earth," she said. "We thought a lot about it, and cosmonauts shared some life hacks."

Shipenko, 38, has made several commercially successful movies, including "Kholop", or "Serf", a 2019 movie that set a Russian box office record. He also described the training as tough. 

"Of course, we couldn't make many things at the first try, and sometimes even at a third attempt, but it's normal," he said.