A spate of congressional interest in the goal of sending humans to Mars has cropped up in the past few months along with calls by space policy commentators for NASA to define a roadmap for human spaceflight. The Human to Mars Summit conference in Washington last week added to the discussion.   

In recent weeks, hearings in both the U.S. House of Representatives and the Senate featured the goal of sending humans to Mars. Lawmakers asked about a roadmap leading to Mars and options for potential interim destinations. They also questioned how the proposed asteroid redirected to a lunar orbit was relevant to the Mars goal. NASA’s rollout of the Asteroid Redirect Mission (ARM) concept last year inadequately presented the context of its rationale and failed to fully describe its connection to the goal of enabling humans to reach Mars. I think that is now being corrected. 

Five-and-a-half years ago the Planetary Society developed a roadmap, “Beyond the Moon,” based on a broad study that included a Stanford University workshop with 50 leaders from various parts of the space community. It laid out a step-by-step series of milestones leading to a human Mars landing, emphasizing an ever-increasing series of human flight accomplishments — beyond the Moon and farther into the solar system with longer flight durations. 

In 2009 the Review of U.S. Human Space Flight Plans Committee, chaired by former Lockheed Martin Chief Executive Norm Augustine, presented the concept of a so-called Flexible Path into the solar system to counter what it described as the unsustainable existing plan to return to the Moon and build a lunar base. The Planetary Society roadmap, published a year earlier, was very similar to the idea of a Flexible Path. At the time the ARM concept had not been developed — but the steps of lunar orbit, beyond the Moon and asteroid interim destinations were specifically cited.

President Barack Obama essentially adopted the Flexible Path in 2010 when he set out goals for human spaceflight: to reach a near-Earth asteroid by 2025 and the vicinity of Mars in the 2030s, culminating in a landing around 2040. I believe this path, with the deep-space asteroid milestones on the way to Mars, is a path we can all follow. 

The major problem (as always) is the first step. 

Even with Congress specifying support for human spaceflight by mandating a new launch vehicle with the Space Launch System and building a new crew vehicle with Orion, we cannot reach a near-Earth asteroid with capabilities projected for the next decade. SLS/Orion cannot reach much beyond the Moon, and thus under current plans any first step would be doomed to go to empty space, years before the development of new capabilities to reach more distant milestones. That will diminish public interest and delay further accomplishments in space exploration.

This is where the Asteroid Redirect Mission comes onto the path — it provides the first milestone. We can’t reach an asteroid with humans, so we bring it closer to us with an ingenious robotic mission and thereby provide a first step to an interesting destination for human spaceflight beyond the Moon. 

This is American ingenuity at its best, moving part of the solar system to enable human spaceflight to a new accomplishment beyond the Moon — something no other nation (or private company) can even think of doing, well beyond trying only to duplicate our achievements of 40-plus years ago. 

The milestones deeper in the solar system will come within reach as we commit to bigger vehicles and longer-duration life support in the decade of the 2020s. Then we can reach more distant near-Earth asteroids, the martian moons (Phobos and Deimos), and ultimately Mars itself. But these achievements won’t come if we can’t take the first step by advancing human spaceflight capabilities in an interesting — indeed exciting — adventure, exploring a redirected asteroid. 

Space enthusiasts feel ARM is too small a step because it’s only at lunar orbit. But ARM is hard enough — and adventuresome! It is audacious to move part of the solar system to make a meaningful and exciting test advancing human spaceflight. Astronauts extending their flight duration and their ability to do exploration on a celestial body, maybe extracting some water or platinum to bring back to Earth, isn’t all we want. We wish it could be in deep space, but it is in deeper space than humans have ever been before, and there is no money or politics on the horizon to take us any deeper. 

With astronauts doing something exciting and interesting and harnessing our combined talents in robotic and human spaceflight, we can restore NASA’s can-do image, inspire the public and lead to Mars. 

We have a dichotomy — the popular interest in a humans-to-Mars goal and the political interest in limited funding, step by step, year by year and contract by contract. This is why the Augustine committee came up with the Flexible Path — to start out to Mars with interim steps. It’s time to get on that path. 

Dr. Louis Friedman is executive director emeritus and co-founder of the Planetary Society.

Louis Friedman is the co-founder and Executive Director Emeritus of The Planetary Society. Prior to that he was Manager of Advanced Programs and the post-Viking Mars Program at JPL.