编者按：《火星救援》的上映再次激发了关于宇宙的科幻狂潮，它和此前上映的《星际穿越》、《地心引力》一同构成三部曲，带领人们触摸最遥远的未知与无限。

An astronaut is stranded in space. Time is running out. Resources are scarce. When things do look like they're about to get better, they find a way to get worse. In an environment where life cannot exist, our astronaut must rely on wits, intelligence, science, and maybe even a little faith to survive.

This is the plot of Ridley Scott's The Martian, which is currently in theaters. It is also the plot of Christopher Nolan's Interstellar, which came out last year. It is also the plot of Alfonso Cuaron's Gravity, which arrived the year before that. Entirely by accident, a trilogy of movies ("The Totally F--ked Astronaut" trilogy) has formed before our very eyes in the past three years. Each movie is directed by a filmmaker renowned for their technical prowess. Each movie physically and emotionally punishes the movie star in the lead role. Each one makes the audience wonder how far they would go to survive. And each one is completely and totally different.

What differentiates The Martian from its brethren in the trilogy is its optimism. Mark Watney (played with warm humor and intelligence by Matt Damon) didn't come to Mars to save the planet. He goes to Mars because he can, because he's curious. He's a scientist and that's what scientists do. They learn, soaking up knowledge like a sponge and taking the results back home to serve humankind. After he's stranded on the red planet, he doesn't stay alive because he has a wife and kid back at home (the screenplay only mentions his parents once). He survives because he won't give up on himself. He's hopeful. He believes that every problem has a solution, even if that problem involves duct tape.

The Martian is very much a procedural, feeling more like Apollo 13 than a typical science fiction adventure, following a crew of cooperating super-geeks as they push the boundaries of human knowledge to save a single human life. In the end, everyone agrees: all of the trouble and energy and sleepless nights were worth it. "I love what I do," Mark says as he's barely surviving on a diet of potatoes and half-rations.

We must go to space because humans are explorers, first and foremost.

Interstellar takes place in a world where the optimism of The Martian once existed and vanished, along with most of the world's food. Matthew McConaughey's Cooper doesn't go into space because he can -- he goes because he must. If he doesn't, the world, along with his children, die. In order to save the world, he must work with the remnants of NASA to resurrect a shaky dream. And then he must ride that shaky dream through a wormhole and hope to find a planet capable of sustaining human life.

Unlike The Martian, which feels grounded in science that feels mostly plausible and comes straight out of a decent science textbook, Interstellar is dealing with theoretical science, stuff that human beings have never actually encountered firsthand. Wormholes, black holes, planets where those on the ground age faster than those in orbit, etc. The film tries to take these concepts, which are tough to wrap your brain around in any context, and connect them to human emotions. There's something strange about a film so full of advanced scientific ideas ultimately delivering a message about how faith conquers all and how the laws of the universe bend in the face of love. Interstellar is a broad film filled with huge emotions, a tear-jerking, all-or-nothing pile of ideas, some half-baked and others cooked to perfection.

We must go to space because that's where the answers are.

And that brings us to Gravity, which is a full hour-plus shorter than its companions. It's the lightest on plot, but the heaviest on technique, more of a roller coaster than a movie. That's a compliment, though. This is exhilarating cinema, a mesmerizing ballet of chaos that was mostly created in a computer, but who cares? It looks real enough. Ant it's all thrilling enough that you ultimately don't care about the wonky science or the thinly sketched characters. Why did Sandra Bullock's Ryan Stone become an astronaut? What is her job on the space shuttle? Does she -- OH! IT'S A DEBRIS FIELD! EVERYONE'S GOING TO DIE.

Gravity is fun. Really fun. If you missed it in theaters, you missed out. It's a one-of-a-kind thing. And while it does have things to say about holding on and letting go (both literally and metaphorically), any and all messages about space exploration and science get lost in the shuffle. That's okay. Cuaron isn't interested in that. However, unlike Interstellar and The Martian, which yell from the rooftops about how space travel is a necessity, Gravity is like an ant-NASA ad. Space will kill you, guys. Really. Stay out.

We must go to space because...holy crap, let's not go to space, okay?