The stuff we're doing right now, on (and around) Earth
This year is actually pretty important for Mars exploration — but not because of anything directly related to Mars. Right now, there are two astronauts about halfway through a year-long mission on the International Space Station. They won't break spaceflight records — Russian cosmonauts shattered the one-year mark several times back in the 1980s and '90s — but this is the first time that scientists will be closely monitoring astronauts undertaking such a long flight.
And even better, one of the astronauts involved has a twin. That means that scientists can study how their bodies change and remain the same during the year that one is on the ground and one is hurtling around the Earth.
This data will help scientists understand how long-term spaceflight affects the human body. That's important, because NASA has estimated that a trip to Mars would take about six months each way. NASA is calling this the "Earth Reliant" phase of our journey to Mars.
The stuff we'll do around the moon in the near future
One of the biggest aspects of the so-called "Proving Ground" phase is the asteroid redirect mission:
Consider, for a moment, that humankind hasn't landed on the moon in over 40 years. We're out of practice! Space technology has come a long way, sure, but we've been focused on making incredible rovers and satellites and making the most of our time on the International Space Station. If we want to build our way up to landing on Mars, we need to get in some practice — and a lot of research and development — in human planetary landings.
The moon is an obvious choice, though it seems unlikely that NASA will opt to build a moon lander. It's possible some international partner or private company will step up to the plate.
But in the meantime, our big practice event involves lassoing a piece of an asteroid and tugging it into the moon's orbit. It's a step down from the previous plan of taking a whole asteroid into the moon's orbit, and an even bigger step down from the first plan — which was to land astronauts on an asteroid itself.
It's a great step — putting humans "deeper" into space than ever before — but will completing such a mission have us ready to jet off to Mars? Some are skeptical.
Actually getting there
The final step of NASA's plan is called the "Earth Independent" phase. This is where we take everything we've learned in phase one and two and start dipping our toes into the edge of the pool.
We don't have to jump straight to sending people to the surface of Mars. We could start with a trip that made a nice low orbit, or even take a trip to a Martian moon.
And once humans do land on Mars — whether it's in one decade or a dozen — NASA scientists will have the opportunity to maximize what we can do there. It's hard to figure out how to extract water on Mars or build the best shelter there if you're not right in the middle of it. So in addition to closely studying the samples we've had to see through the eyes of rovers, the first astronauts on Mars will no doubt be doing some serious experiments to determine the best way to live there long term.
Establishing a permanent outpost on Mars is a lofty goal, but the plan certainly makes it sound plausible. Unfortunately, poor planning isn't the kind of pitfall NASA has to worry about. The real issue is funding. Without continued public support and excitement (and perhaps even with it) it's doubtful that NASA will ever get a "one small step" moment on the Red Planet.