Directed by James Gray and starring Brad Pitt, Ad Astra is 20th Century Fox’s latest space adventure film, which aimed to depict the most realistic take on space travel, at least in the somewhat near future. In order to make sure the creative and production teams were on the right track, they enlisted the help of Robert Yowell, a former NASA engineer who now manages space projects for the U.S. Air Force in Los Angeles. He also works as a technical consultant on films such as Ad Astra.

Here’s what Yowell had to say about Ad Astra’s scientific accuracy, the future of space travel, and how the film industry has progressed in its depiction of space in general:

A lot of space movies are set in the “near future”, but how near would you say Ad Astra is?

As a technical consultant, do you often find yourself reining in what people think of future space travel or are they surprised to find out that certain things, like commercial space flights, are closer than we expected?

If you take into account the advanced propulsion methods shown in the film (likely nuclear or plasma propulsion), it is probably several decades in the future.

Was there anything in particular that you were happy to see in the film - something that was brought to life in a scientifically accurate way? On that note, is there anything that was notably inaccurate?

I think today thanks to people like Jeff Bezos, Elon Musk, and Richard Branson, people are much more accepting of commercial human spaceflight as a reality.  This has only been made a reality in the last decade, which gives you an idea of how quickly this industry has evolved.  While we don’t yet have regularly scheduled “space lines,” we are much closer to that reality today than ever before.

Ad Astra is one of the final space movies of the decade, so how would you say the depiction of space travel has evolved in Hollywood throughout the 2010s?

Considering this film is science fiction, not science fact, there is really no way to say anything in the film is truly accurate or inaccurate. In order to make an entertaining film, it must stretch the limits of reality. That being said, there were a few scenes which I thought “looked” accurate - such as the Mars landing scene. While we don’t yet have the type of fully throttleable nuclear plasma engine as shown in the film, the sequence of Roy taking control to manually fly the last portion of the landing was very well done - both visually and dialog wise. As far as inaccurate, I don’t think an astronaut on Mars could easily run up the side of rocket booster during launch as Roy does - but again, that is part of why a film like this is entertainment, and not a documentary!

Taking everything from Ad Astra into account, what technology or achievement is the furthest away? People on Mars, colonization of the Moon, a space antennae, etc.?

The 2010s have produced some fantastic space films, and Ad Astra is the perfect denouement for this sequence.  Certainly The Martian gave a very realistic view of what it would be like to be the first pioneer explorer on that planet “living off the land.” Gravity gave a very realistic visual representation of the amazing view an astronaut sees through his or her helmet visor when doing a spacewalk around the earth. Interstellar presented a very interesting concept of how interstellar flight could be possible someday using actual theories of quantum physics. As for the non-fiction space films, both Hidden Figures and First Man provided excellent accounts of some key moments in American spaceflight history. In the case of Hidden Figures, it gave some much overdue and deserved reverence to a group of women who broke racial and gender boundaries in what was until then the very white and male dominated field of spaceflight.

What in particular do you hope to see in future space movies?

I would say probably colonizing the Moon is the furthest away from now in the list you have. We will likely have the first people on Mars in the next 20-30 years. Colonization of the Moon, in which you would have thousands of people living there, is likely at least 50 years away. The nuclear/plasma powered spacecraft allowing you to fly to Mars and the outer solar system in a fraction of the time it takes chemical propulsion, may not happen until the next century.

Next: Ad Astra’s Ending Explained (& Why It Isn’t Really A Sci-Fi Movie)

I am a bit biased in answering this question since I spent the first part of my career working as a flight controller in mission control for the space shuttle program. I would love to see a film depict dramatically not only the story of how and why the space shuttle was developed, but also the tremendous bravery and risk of the two astronauts who flew onboard the first space shuttle mission in April, 1981. This is a topic of which most of the public is still unaware today. The fact that the space shuttle is the only human spacecraft that ever made its first flight with people onboard is still staggering to think today.

Every US spacecraft which flew before it - from Mercury, to Gemini and Apollo, and every spacecraft since - the SpaceX Dragon and the Boeing Starliner made at least a few test flights without people before astronauts ever rode on them. That was not the case with the space shuttle - so John Young and Robert Crippen were the ultimate test pilots on that day in 1981. And even after they made it into space, there was still uncertainty they would make it home alive because of the missing tiles that they could see outside their window when looking at the spacecraft. This would really make a compelling film if done right!

Ad Astra is now available on Digital and releases on 4K Ultra HD, Blu-ray, and DVD on December 17.