MICHELE NORRIS, host:
From NPR News, this is ALL THINGS CONSIDERED. I'm Michele Norris.
NOAH ADAMS, host:
And I'm Noah Adams.
If all goes well this weekend, an emissary from Earth will land on Mars. NASA's Phoenix probe is scheduled to touch down near the Martian North Pole on Sunday. This probe is not exactly like the rovers that are still rolling around on the Martian surface. The Phoenix will stay in one place for its 90-day mission. But it is carrying sophisticated equipment that will help answer the big question: could Mars have ever harbored life?
NPR's Joe Palca has a report.
JOE PALCA: Here's a little quiz. What do the following space missions have in common?
LYNN NEARY: Cosmos 419.
ADAMS: Mars 2.
NEDA ULABY: Mars 6..
CLAUDIO SANCHEZ: Mars 7.
PAM FESSLER: Phobos 1.
RICHARD HARRIS: Phobos 2.
JESSICA GOLDSTEIN: Mars 96.
COREY FLINTOFF: Mars Polar Lander.
NELL GREENFIELDBOYCE: Beagle 2.
PALCA: If you said they're all missions to Mars, that's correct. But that only gets you partial credit. What's significant about these nine spacecraft is that they were all suppose to land on Mars and they all failed. That will help you understand why scientists talk like this at news conferences when a mission actually succeeds.
(Soundbite of archived video clip)
Mr. PETER SMITH (University of Arizona): The joy that fills my heart has overflowed my body and risen to the heavens and has reached to Mars.
PALCA: That was Peter Smith on July 6, 1997, two days after the little bitty Mars rover known as Pathfinder bounced safely down to the Martian surface. Smith is a planetary scientist at the University of Arizona. He led the team that built the main camera on Pathfinder as well as the main camera for Mars Polar Lander that crashed. Now he's the scientist in charge of the entire Phoenix mission that will reach Mars this weekend. Being in charge is not a job he particularly wanted, as he told reporters last week.
Mr. SMITH: Well, I've experienced a wonderful success with Pathfinder in building the camera. And then the very disappointing failure with Polar Lander when we had no pictures returned from our cameras. But by gosh, we spent 15 years developing the hardware and I really wanted some return from those. So I had to take on the entire mission to do so. But that's what I have to do and that's what I'm going to do. And by God, we're going to get pictures.
PALCA: The pictures will come from the same camera that was to fly on the cancelled mission. In fact, a lot of the hardware is from the mission that died bureaucratically before it left the ground; hence the name Phoenix for the current mission.
Today, all the successful Mars landings have been relatively close to the dry equatorial zone on Mars, where not much besides dust storms has been happening for billions of years. Phoenix, on the other hand, is going to the far North of Mars. For comparison, a similar place on Earth would be the North Coast of Canada. Smith says scientists know there is plenty of water in the form of ice near the Martian Poles.
Mr. SMITH: By landing on the ice in the northern plains, we're looking at active processes that is taking place today. And these active processes have to do with the expansion and contraction of that ice throughout the seasonal changes. We're going to see climate change written into the soil.
PALCA: In addition to the cameras, Phoenix has onboard chemistry labs that will allow scientists what kinds of chemicals and minerals are in the Polar soil. While the labs can't detect life, they can tell us conditions were once favorable to life, where the water wasn't too acidic or too salty for life to exist. Phoenix left for Mars last August. Project manager Barry Goldstein says the spacecraft has been thoroughly tested and they have found problems. But Goldstein says it's not the problems they found that makes him and everyone else associated with the mission nervous.
Mr. BARRY GOLDSTEIN (Project Manager, Phoenix Project): What scares every each and every one of us is what is it we haven't thought about in the system? What is it we don't know?
PALCA: With luck, whatever they haven't thought about will be minor. And by next week another NASA mission will be sending data back from Mars.
Joe Palca, NPR News.
ADAMS: Humans have tried to reach Mars 39 times; more than half of those missions failed. You can get the highlights of these earthly attempts to film, orbit, and touch the Red Planet at npr.org. Transcript provided by NPR, Copyright NPR.
