NASA this week released a detailed plan explaining how it intends on sending humans to Mars. And the plan isn’t just to visit the planet and come home. Rather, NASA’s ultimate goal is to send a group of intrepid explorers to the Martian surface with the ultimate goal of being “Earth independent.” NASA wouldn’t go so far as to say we’ll successfully colonize Mars, though the agency seems optimistic about the planet’s potential to sustain life.

The plan includes three thresholds: Earth Reliant, Proving Ground and Earth Independent. Earth Reliant includes research being conducted aboard the International Space Station (ISS), where experiments will help scientists determine the longterm effects of deep space travel. Proving Ground takes that a step further, and tests the requirements for humans to live and work at distances far away from our home planet.

Earth Independent is the most crucial step of all, and will ultimately decide if we can embark on human missions to the Mars vicinity, and eventually on the planet’s surface. NASA has already set a budget for its journey to Mars, and plans on taking some big steps toward its goal as early as the 2020s, with plans to test its Orion spacecraft with humans onboard. NASA has already successfully tested the shuttle without anyone in it.

“NASA’s strategy connects near-term activities and capability development to the journey to Mars and a future with a sustainable human presence in deep space,” said William Gerstenmaier, associate administrator for Human Exploration and Operations at NASA headquarters.

NASA released a fascinating infographic that illustrates how it hopes to meet and exceed the three different thresholds on its journey to Mars. It also shows the kind of obstacles NASA needs to overcome to even get to the point of Earth independence. We’ve been on and around Mars for 40 years already, using orbiters, landers and rovers to study the planet’s mysterious past. The next step is for humans to set foot on the Red Planet and actually study it in person.

NASA has already said that the first person to step on the Martian surface is already walking the Earth. With a clear and purposeful path laid out, can the agency and its partners actually achieve their goal? More importantly, can Mars, which evidence suggests was once covered in water, support life? These are the questions NASA hopes to answer maybe as early as the 2030s.