Mars rises far above the western horizon in the summer skies over Tucson. Looking up from Earth, the planet is just one point of faint reddish light against a vast backdrop of space and stars. Those on Earth know there is a piece of Arizona out on that rock. They know because they have been told that three weeks ago UA scientists took control of NASA’s Phoenix Mars Lander after it touched down on the planet’s surface. What might be harder to wrap their minds around is why it’s out there in the first place.

Peter Smith, the mission’s principal investigator, summed up ‘Phoenix’ and its mission. “”We’re part of the search for life on Mars,”” he said.

Stare upwards too long with that in mind and one is liable to get starry eyed. ‘Phoenix’ is actually parked on that rusty pinpoint. That sphere out in the blackness is where UA scientists have planted the flag in their search for life in the universe. The UA is going to finally answer that ultimate question, “”What’s out there?””

The reality of the mission might bring you back to Earth. A public affairs officer for the mission put the price tag at $420 million. Even at that price tag, ‘Phoenix’ won’t buy instant results.

“”This is a long-term program, searching for life,”” Smith said. “”It’s not easy. If life were easy to find on Mars, it would have been done long ago.””

The ‘Phoenix’ mission will be long and complicated and is only one piece in the puzzle that is NASA’s greater search for life on Mars. Smith said that ‘Phoenix’ isn’t even equipped to detect proof that life exists, or ever existed, on the planet.

To reiterate, there is zero likelihood that ‘Phoenix’ will discover life on Mars – just tantalizing hints.

Rather, ‘Phoenix’ is one part of a process to discover life. That process is not designed to produce hard and fast answers. Smith described the mission as only the second step in a three-step search for life.

The first step was to find water, which is essential to all known forms of life. The Mars Odyssey Orbiter accomplished this on Mars in 2002. Discoveries made by the orbiting spacecraft showed the existence of large amounts of frozen water underneath the surface in the northern Martian arctic, according to ‘Phoenix’ mission fact sheets provided by NASA.

NASA has described its science strategy towards Mars as a game of “”follow the water.”” Six years since Odyssey made it’s discovery, ‘Phoenix’ has touched down on Mars’ northern plains to follow that water. That’s where the next step comes into play.

Step two is to discover whether or not life could actually exist on the planet. The mission team’s job is to find “”habitable zones”” on the planet that are capable of supporting life. These conditions include liquid water with complex organic materials such as amino acids, which are some of the building blocks for life, Smith said.

Finally, step three is to discover if any of these habitable zones are actually inhabited. This step is reserved for future missions. Reaching this stage is not even a foregone conclusion. Step three depends on ‘Phoenix’ or another mission actually discovering one of these “”habitable zones.””

Mission scientists have a couple strategies to find these habitable zones. They will use the Lander’s array of instruments to test for evidence that liquid water once existed on the planet’s surface. Scientists will also test the soil for life-giving elements like carbon to see if even now the Martian soil could support primitive life.

Such a venture is actually possible because certain bacterial spores on Earth have been known to lie dormant for millions of years in dry, airless and bitterly cold conditions.

But even if ‘Phoenix’ hits the mother lode, does the existence of habitable zones guarantee the presence of Martian life?

“”No, no, no. If we introduced organisms to these locations, it means they could live there,”” Smith said. “”The necessary ingredients for life to exist don’t mean it’s there.””

In other words, the search for life is not a sure thing.

We, as humans, can look into space and know that ‘Phoenix’ is in the great beyond scratching out samples of soil on the Red Planet. What we don’t know is what ‘Phoenix’ will find.

We know so little of the answer to that question that Smith told reporters, “”Anything we find is going to be a revelation to some scientist in this country.””

So what’s out there is whatever we find. But there is so much “”out there”” out there, it might also be easy to ask yourself, “”What’s the point?””

Smith said that’s a question people have to answer for themselves.

“”I don’t know. It depends on your philosophy of life, I suppose, if doing things are interesting or not,”” he said. “”Maybe we could spend our lives reading fantasy books and going to the movies, but if you want to understand the world around you and if you believe that scientific inquiry is a valuable pursuit, then missions like this are absolutely crucial.””

If pure scientific inquiry is the prize that ‘Phoenix’ is after, then it seems poised to return big dividends. Smith has described the ‘Phoenix’ landing site as “”incredibly science rich.”” Within days of the landing, mission officials announced that ‘Phoenix’ had returned pictures of what might be ice. ‘Phoenix’ seems poised to return reams of data back to Earth.

The mission is not just returning scientific data, though, said Rick McCloskey, a UA engineer who tested many of the instruments that are being used on Mars.

“”I think you’ll always take away practical knowledge from (the mission),”” he said. “”…we learn a lot by taking this equipment and readying it for space. We’re just taking engineering one step further.””

In fact, the engineering that scientists learn from taking on missions like ‘Phoenix’ can also lay the groundwork for even more involved missions, McCloskey said.

“”Who knows, our next step may be for mankind to go there,”” he said.

However, if ‘Phoenix’ does not discover the conditions for life – its primary mission – the more piercing question may be, “”Has this whole adventure been for nothing?””

Coming to that conclusion is not fitting with the spirit of science, said Jacob Egan, a graduate student in optical sciences who does public outreach for the mission.

“”It’s scientific process,”” he said. “”It’s forming a hypothesis and testing it. Even if it’s disproved, you’ve still learned something.””

He said such an attitude rings true for the scientists at ‘Phoenix’ down to the kids whose science fair projects he’d judged as part of his outreach for the mission.

“”Kids have to learn that just because you didn’t find what you’re looking for doesn’t mean that you’re wrong,”” he said. Egan suggested that lesson applied to adults as well.

Still, that scientific process is painstaking and uncertain, years and millions of dollars in the making. From Earth, the Red Planet can also appear as just an orange-colored speck, epically far away. ‘Phoenix’ has traveled 423 million miles from the worries of everyday Earth, like gas prices and student loans. Smith and Egan have both said that ‘Phoenix’ will at least learn something, but it’s also easy to turn your eyes from Mars back to ground level and ask yourself, “”What else could we be spending this money on?””

Egan said that, if you compare the price of ‘Phoenix’ to some other real-world expenses, the mission is still a pretty good deal.

“”I relate it back to ‘Pirates of the Caribbean,'”” Egan said. “”That trilogy cost something like $600 million. Ours cost $420 million. I enjoyed the movies but they didn’t really enrich our knowledge of the world around us.””

That may be so, but “”Pirates”” is not a government agency like NASA. Would government dollars be better spent elsewhere?

A stalwart defender of the mission, Smith said that to forgo space exploration would be a mistake.

“”People say to me ‘Well, you could go out and solve questions of poverty on this earth by not doing these missions,’ and I know that’s not true,”” he said. “”You’re not going to solve poverty and people with poor health by not doing these missions. These problems will always be with us… it’s never going to go away. Those questions should be addressed but we should also do space missions.””

Not to do so, he said, would squander an historic opportunity.

“”It’s only – think about this – there’s been 10,000 years of human history going back to the Egyptians and Mesopotamians,”” he said. “”It’s only today that we can do this, after 10,000 years.””

Smith is a true believer in the cause, but the excitement of the opportunities he describes doesn’t appear to be lost on the rest of the planet. The world’s collective neck has been craned towards Mars the past three weeks as mission officials have held almost daily briefings for international media. Egan said that the team had received letters of congratulations from people all over the world. He described the reaction to the mission as “”99 percent positive.””

“”There’s nothing more exciting that putting one of these puppies on the surface of Mars,”” McCloskey said.

So you can forgive yourself for looking up into the sky and saying, “”Wow.””

But if you’re looking out there and asking, “”Why?””, Smith has an answer for you: Because we can.

“”People ask me all the time ‘Why should we do it?'”” Smith said. “”I’m thinking, ‘Why shouldn’t we do it?'””

The mission won’t be easy. But for Smith, it’s worth it.

“”My god, it’s the first time we’ve been able as a human society to do something so great as to go to other worlds and explore them,”” he said.

“”Why would you not do it?””