Kevin R. Grazier is a planetary scientist and friend of mine who has regularly landed gigs as a science consultant on a number of popular Hollywood movies and TV shows. He’s also written or edited a number of pop science books like The Science of Battlestar Galactica and The Science of Michael Crichton, among others. I recently sent him some questions to answer with respect to the upcoming movie Gravity, which frankly looks very promising to me based on its trailers.
Q. Congratulations on being chosen as the science adviser for such a high-profile movie like Gravity. Can you describe how that happened?
Thank you. The amazing amount of attention this film has been receiving of late has rather crept up on me. There have been some delays in the film’s release, and my input into the film ended over 3 ½ years ago. That’s nearly the duration of an entire undergraduate degree program. I’ve actually had to dig back through my hard drive, and find the notes I submitted back then in order to recall what input I’d given them.
The Cuarons (Alfonso and Jonas co-wrote the screenplay) contacted the Public Information Office at JPL, where I worked at the time. Since I’d done a lot of similar consulting on TV series like Battlestar Galactica and Eureka, JPL’s PIO forwarded them to me.
Initially I met Alfonso and Jonas in the lounge at Chateau Marmont in Hollywood. We talked about my background, about their inspiration and vision for the film, and about some of the pre-production CGI they already had completed for the film.
Alfonso had seen the 3-D IMAX film about the final Hubble servicing mission, and he was so inspired by that film that he wanted to create a movie that gave audiences a real “You Are There” feel about space exploration. From the onset it was clear to me that he was super keen on getting as many details, both subtle and gross, as accurate as possible, while still telling a compelling story. We spoke for a few hours there in the lounge, and I received a script from Warner Brothers that evening.
Alfonso wanted to know details as specific as which direction switches on the shuttle flipped, and which direction hatches opened on ISS. In the end, some of his questions were simply beyond my experience. As luck would have it, at that time I was working half time on the Constellation Program (the program that was designed to return humans to the Moon and Mars). I had just spent a week in Houston, and there I’d met Andy Thomas, head of the astronaut program. So I connected the Cuarons with Andy. When they asked him details about the Russian Soyuz capsule—the ISS “lifeboat”–Andy said, “I have no idea, I’ve never been up in a Soyuz, but my wife [Astronaut Shannon Walker] is going up on one in a week. I bet she knows.” So by tag-teaming it, we got them the information they needed.
Q. Can you describe what exactly a science consultant does?
A science advisor’s job is to help ground the fictional science of a science-themed or science fiction production in the science of the real world. For many viewers, particularly the science-literate, technical mistakes—particularly ones that simply didn’t have to happen—will pull them out of the story and out of the creative vision of the storyteller. By making the science appear as real as possible on screen, the storyteller avoids those dreaded “Oh PUH-LEEZE” moments.
The input from a science advisor can manifest in many different ways. It can entail helping the storytellers with science concepts, writing technical dialogue, providing the talent the correct pronunciations for technical terms, input on the culture of science and scientists, even input into special effects. I didn’t do all of those for Gravity, but I have done all of those at some point.
Q. The initial trailer for Gravity is really exhilarating, and masterful in terms of being such a single, long shot in the space environment. I’ve never seen anything like it. The destruction is really amazing. Is that much damage from debris in low Earth orbit plausible? Could it really set the shuttle spinning like that?
Is that much damage possible? Probably, but certainly so for the level of scientific veracity needed to tell this story. The premise of Gravity rests upon a conjecture called the Kessler Syndrome. The idea is that a satellite, though whatever means, could be destroyed and, in the process, generate a cloud of debris. Some of that debris could strike, and destroy, other satellites leading to more debris and eventually an entire cascade of collisions.
As far as setting the shuttle spinning… Perhaps the most common class of science or technical inaccuracy in TV and film involves the rates at which phenomena progress – where the rate is either decreased or (more often) increased to dramatic effect. That could be the case here, but then again perhaps not. Depending upon the speed and mass of the impactor, I don’t doubt that such a collision set a shuttle spinning at a rate beyond the RCS system’s ability to cope. Spinning as fast as we see in the film? I’m not sure, but even if the answer is “No,” and the wing would be sheared by the impact rather than sending the spacecraft spinning, I certainly don’t think the scene looks unbelievable to the very large majority of the audience.
Q. It seems that the ISS is a likely safe haven for these astronauts. Is it possible to reach the ISS in a reasonable time from a shuttle mission to some other orbit? Given that the longest EVA to date is about 9 hours, this seems potentially challenging.
Succinctly, there’s no way that, in its current orbit, astronauts could get from Hubble to ISS with the O2 available to them for one EVA. At the absolute tip-top best, if everything was perfect, at the very least they would have to traverse a distance roughly equal to that from LA to the border of Mexico.
To that I say, so what? This is a film, and we either give our characters a goal to shoot for, or watch as they each asphyxiate alone in the vacuum of space. There are some who would call that “dramatically uninteresting.”
So, yes, I did discuss the relative orbits of ISS and Hubble with Mr. Cuaron. I also threw out the idea that our heroes were servicing a different space telescope, one that was in an orbit closer to that of ISS. I even suggested that we call it the Cannon Space Telescope (after astronomer Annie J.), and then hit up Canon Cameras for product placement dollars. His response was, “You missed your calling in life, you should have been a producer.
In the end, true to the original motivation from the IMAX movie, and the vision of taking the audience on a trip to service the HST, the mission remained a HUBBLE servicing mission. That said, who could have foreseen that, a couple years later, the U.S. intel community would donate two spy satellites to NASA that could function as Hubble-class (or better) space telescopes.
Q. Clooney tells Bullock to detach from the spinning arm. Was that wise? Would it be easier to find her and the arm than her alone?
Although being attached to the arm may make it easier for her to be seen from a distance, that arm is far more massive than the astronaut attached to it, and has one heck of a lot of momentum as it careening away from Explorer. It’s far more realistic that they could come up with enough delta-V to arrest the velocity of Dr. Stone alone, than it is for them to be able to slow the combined mass of Dr. Stone and the SRMS.
Further, while attached to the rotating arm, Dr. Stone’s instantaneous velocity is the vector sum of the center-of-mass motion of the arm, plus her rotation about the center of mass. Depending upon where she detaches, she could get a pretty good kick back towards Kowalski, and back towards Earth.
Q. In the pantheon of realistic space-based movies, where will Gravity rate? Will we be able to compare it favorably to Apollo 13? Or should it really be judged in a different category?
Gravity belongs in a different category than Apollo 13. Apollo 13 is a very faithful telling of an historical event; Gravity is a “what if” film. The attention to detail, the amazing special effects, and the stunning 3-D (in other words, technology 18 years more advanced) may give audiences a better sense of being on an actual space mission than did Apollo 13, but I think that just leaves them both as the top representative of two different classes of movies.
The one category in which I hope Gravity is judged is the Best Picture category for the Academy Award.
Thank you, Kevin. I look forward to watching the movie soon!