NASA’s Phoenix lander will seek clues to life on Mars

The search for life on other worlds can be boiled down to a simple maxim: Follow the water. Life, at least the carbonaceous form we are familiar with, loves water.

Now, for the first time, NASA is about to land a spacecraft in a place on another planet where scientists are confident water exists. The Mars Phoenix lander is set to blast off from Cape Canaveral early Saturday for a journey to near the Martian north pole.

Once there, it will extend a 7-foot-long robotic arm to dig to a layer of ice thought to lie just beneath the surface. If the ice is as hard as some scientists suspect – think concrete – Phoenix will use a tungsten carbide drill to bore into it.

The soil and ice will be analyzed by the most sophisticated suite of scientific instruments ever sent to the surface of another world. The instruments will scan, magnify and cook the compounds, finally sending them through a mass spectrometer to identify their parts.

“The Holy Grail would be to find organics,” said Barry Goldstein, the project manager at the Jet Propulsion Laboratory in La Canada Flintridge, Calif. “That would be a major splash.”

Finding organic compounds would not be proof of life. But it would be a major step forward in proving that Mars could be, or once was, a habitable place.

“We hope it will move us closer” to answering the life-on-Mars question, said project scientist Leslie Tamppari.

For two decades after the Viking missions of the 1970s, Mars was considered a dead-end world. “Self-sterilizing” is the term scientists used to describe a place that the Viking instruments found to be more barren than the harshest deserts on Earth.

Now the story has changed. NASA’s two Mars rovers, Spirit and Opportunity, have found evidence that water once coursed over much of the surface. The orbiting Mars Odyssey spacecraft also detected a large subterranean storehouse of hydrogen at the north pole that scientists are confident is water ice. Then, a few months ago, the Mars Global Surveyor detected from orbit what appears to be evidence of water flows on Mars today.

“We’re going to where the water is,” Goldstein said. “Our plan is to go touch it, taste it, sniff it.”