STS-134 crew members, front row from left, pilot Greg Johnson, commander Mark Kelly, second row from left, mission specialists Robert Vittori, of Italy, and Mike Fincke, third row from left, mission specialists Greg Chamitoffat and Drew Feustel, leave the Operations and Checkout Building for a trip to Launch Pad 39-A and a planned liftoff on the space shuttle Endeavour at the Kennedy Space Center in Cape Canaveral, Fla., Monday, May 16, 2011. (Chris O'Meara/ASSOCIATED PRESS)

Last weekend, my wife, Gabby, and I went to see the movie “Gravity” at our neighborhood theater in Tucson. I’m a retired astronaut who has been to space four times, so I’m usually a bit skeptical of films that take place in space. For me, watching movies about space is like a congresswoman watching “House of Cards.” It’s entertaining, but it’s obviously not the real thing.

Director Alfonso Cuarón does come remarkably close with “Gravity.” I’ve spent a total of 55 days in space so I know what to look for, and Cuarón really was able to capture what it looks like inside and outside of a spacecraft. It’s extremely difficult to film a movie that is almost entirely without gravity. In “Apollo 13,” Ron Howard achieved the effect of zero-gravity flight by filming in NASA’s zero-gravity airplane, the “Vomit Comet.”

Cuarón took a different approach. He and his cinematographer created something they called “the Cage” and relied on lights and the emotions of the actors to bring viewers to a realistic approximation of space.

The actors floating around in spacesuits seemed equally convincing. As astronauts, Sandra Bullock and George Clooney captured the intensity and horror of their situation — essentially, a fight for survival in space. However, it is very unlikely that two crew members would not know each other well, as was the case in “Gravity.” Training to repair the Hubble Space Telescope takes years. As the commander of the mission, you would certainly know where your crew members are from.

It’s true that astronauts have fun, but we are there to do a very serious job. You would never see the commander of the mission flying around Hubble in his Manned Maneuvering Unit (MMU) like he was a kid riding his first bike around the driveway. If we still used the MMU, and we don’t, it would be flown carefully and methodically. The commander would not fly next to the $2.5 billion space telescope that we really care about, nor would he goof off outside in the vacuum of space. During my time in space, our fun was kept inside the spacecraft: We would throw a football in zero gravity — not so easy — and usually watch it head straight to the ceiling, not to our intended target.

Of course, I would fail you as an astronaut and an amateur film critic if I did not touch on the big misconception of “Gravity.” A key plot point involves a space station falling out of orbit because it was hit by debris. But that just doesn’t happen. Likewise, blowing up stuff in orbit makes a big mess, but it doesn’t send a giant field of shrapnel hurtling at high velocity toward a spacecraft that is circulating Earth in an entirely different orbit.

I can say this with confidence, because I’ve dealt with my fair share of space junk. In January of 2007, China intentionally targeted and destroyed one of its satellites, and it made a big mess in orbit. Six months later, I commanded space shuttle Discovery on a mission to the international space station . As one can imagine, we were concerned about the additional space junk. But we knew that we only had to put some distance between us and the debris.

You also can’t just point at things in space, head off in that direction and expect to get there. In June of 1965, Jim McDivitt tried to rendezvous his Gemini 4 spacecraft with a spent rocket casing — and he failed.

At the time, NASA didn’t understand that by pointing at something and accelerating, you increase your altitude, slow down and instead move away.

Today, we know that the best way to join up with another spacecraft is a slow procedure that takes an entire day in the space shuttle — too long for the supercharged momentum of a movie.

But the truth is, most of this doesn’t matter. Cuarón has given us a glimpse of the awe that is the universe beyond our atmosphere. And physics aside, he does it remarkably well.

My only hope is that we continue our exploration of space in real life, too. The majority of NASA employees have been furloughed as a result of the government shutdown. If Sandra Bullock’s Dr. Ryan were a real person, she’d still be waiting on the beach somewhere on planet Earth.

So, do me a favor. After you see “Gravity,” tell your member of Congress. Perhaps it will inspire them to put NASA employees back to work.

Capt. Mark Kelly, a retired Navy combat pilot and NASA shuttle commander, co-founded Americans for Responsible Solutions with his wife, former Arizona congresswoman Gabrielle Giffords.