At a special hearing today, members of the House Committee on Science, Space, and Technology tore apart NASA's Journey to Mars initiative, claiming the program needs a much more defined plan and clear, achievable milestones to work. Those in attendance also doubted the feasibility of a long-term Mars mission; they cited the massive amount of money needed for the trip — much more than NASA currently receives year to year — as well as a significant leap in technological development. Because of these enormous challenges, a few witnesses at the hearing suggested that NASA either rethink its approach or divert its attention to a Moon mission instead.

Above all, Congress members and the three expert witnesses who testified argued that NASA lacks a clear road map for Mars. "We do not have a planned strategy or architecture with sufficient detail," said Tom Young, the former director of NASA's Goddard Space Flight Center. The space agency is currently building a rocket called the Space Launch System (SLS) and a crew capsule called Orion, both of which are supposed to transport humans to the Red Planet. But NASA is going to need a lot more hardware for a Mars trip — including habitat modules, landing systems, and launch systems for a return voyage back to Earth. None of those pieces have been clearly defined by NASA yet, according to John Sommerer, chair of the National Academy of Sciences.

"We do not have a planned strategy or architecture with sufficient detail."

The timeline for the Mars trip is also unclear. The first test flight of the SLS and Orion combo is scheduled for 2018, but beyond that, the rocket’s future is up in the air. The first crewed flight of Orion and SLS is tentatively scheduled for no later than 2023, though NASA is working toward a launch date of 2021; the agency doesn’t have any launches scheduled after that. And while numerous missions have been proposed for the SLS, the rocket is really only slated to participate in NASA's Asteroid Redirect Mission (ARM). That's the initiative where a robotic spacecraft will capture a small piece of an asteroid and bring it into lunar orbit, where humans on the SLS can visit it.

An artist rendering of what the Asteroid Redirect Mission could look like. (NASA)

ARM may be one of the only defined goals of the SLS, but many at today's hearing criticized the mission heavily as well, characterizing it as nothing more than an extremely expensive stunt. NASA has stated previously that the main goal of ARM is to demonstrate new solar electric propulsion technology that the agency wants to incorporate into the Mars mission. But a few witnesses noted that such a demonstration can be done through other, less complicated measures. And Rep. Brian Babin (R-TX) said it was concerning that the main focus of ARM wasn't on studying the asteroid itself. Many planetary experts have claimed ARM doesn’t advance scientific knowledge very much at all. "This is a misguided mission without a mission, without a launch date, and without ties to exploration goals," concluded Rep. Lamar Smith (R-TX). "It's just a time-wasting distraction."

"It's just a time-wasting distraction."

The hearing eventually delved into whether or not the entire Mars initiative is even feasible based on how much it is expected to cost. Sommerer estimated that NASA would need upwards of half a trillion dollars to reach the Red Planet. Researchers will need a lot of that money to create new technologies, as well as engineering solutions to challenges the crew will face during the trip, he said. A big concern is the deep-space radiation exposure astronauts will experience en route to Mars. But NASA currently has no technical solution for the radiation risks, and even more money will be needed to develop one.

Given how much funding NASA needs, the committee says it is even more critical that the agency develop a concrete plan, especially with a new presidential election on the horizon. A clear vision will be necessary to receive the money and support needed from a new administration. Otherwise, the initiatives face the risk of cancellation.

But Sommerer and fellow witness Paul Spudis, a senior scientist at the Lunar and Planetary Institute, testified that NASA should consider returning to the surface of the Moon instead of going to Mars, since such a mission would provide an equally exciting and much more achievable goal. The international community is focused on establishing a presence on the lunar surface and in the space surrounding the Moon, Spudis argued, so the United States should maintain leadership in those areas as well. Additionally, missions to the Moon could focus on mining water at the lunar poles, to help sustain a human presence on the surface or create rocket fuel for future missions into deep space. "The moon is reachable, it’s close, it’s interesting, and it’s useful," Spudis said.

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