Opinion: Life on Mars? The important thing is to keep looking

It’s exciting news that NASA has just announced evidence of water on Mars. Sure, we’ve heard about frozen polar caps—but that’s ice. And scientists believe that Mars, once, maybe a few billion years ago, had rivers and possibly an ocean. But what caused NASA to call a press conference was to declare that Mars may have intermittent streams of flowing water—quite salty water, in fact.

And nice showmanship on NASA’s part--promising a big reveal on Mars at a press conference just days shy of the opening of the big, highly promoted film “The Martian” starring Matt Damon as an astronaut stranded on Mars.

It’s not like scientists found a coursing Mississippi River—or even an anemic L.A. River. As my colleague, Los Angeles Times reporter Amina Khan, cleverly put it, “what they’ve detected looks less like salty water and more like watery salt.” And there are no photos of the water currently flowing. What scientists discovered, studying data from NASA’s Mars Reconnaissance Orbiter, are dark streaks on the Martian landscape that appear in (relatively) warmer seasons and fade in colder ones.

But finding water, any water, on planets in general, and Mars in particular, is a scientific obsession. It’s not that a sign of water is a sure sign of life. It’s more that no water is a deal breaker when it comes to conditions for life (as we know it.) And here is evidence not just of water at some point in the last billion years but water in the present day. “It suggests that it would be possible for there to be life today on Mars,” John Grunsfeld, associate administrator of NASA’s Science Mission Directorate, told reporters. Lots of questions remain, and it would be difficult for organisms to survive in this very salty water.

Still, this gradual deepening of our knowledge of Mars should spur us on to more exploration and show us how important and compelling these kinds of space science undertakings are. They are expensive and time-consuming, but they literally expand our world. And all this comes at a time of renewed public interest in space exploration and adventure, fueled by extraordinary new images of Mars and the outer solar system and ambitious plans by entrepreneurs to launch manned missions to Mars. Whether those spaceships ever get off the ground in the next few decades, the desire to learn more about Mars is already in flight.

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