To Mars and back quickly: Improved propulsion technology in works

A concept image of a spacecraft powered by a fusion-driven rocket. In this image, the crew would be in the forward-most chamber. Solar panels on the sides would collect energy to initiate the process that creates fusion.

New propulsion technologies may blast astronauts through space at breakneck speeds in the coming decades, making manned Mars missions much faster and safer.

Souped-up electric propulsion systems and rockets driven by nuclear fusion or fission could end up shortening travel times to the Red Planet dramatically, proponents say, potentially opening up a new era in manned space exploration.

"Using existing rocket fuels, it's nearly impossible for humans to explore much beyond Earth," John Slough of the University of Washington, leader of a team developing a fusion-driven rocket, said in a statement earlier this year. "We are hoping to give us a much more powerful source of energy in space that could eventually lead to making interplanetary travel commonplace." 

Fast track to Mars

Putting boots on the Red Planet is a chief ambition of NASA, which aims to send astronauts to the vicinity of Mars by the mid-2030s.

As it works toward this goal, the space agency is investigating and encouraging the development of advanced propulsion systems to take the reins from traditional chemical rockets, which could get astronauts to Mars and back in about 500 days. That's too slow for NASA's liking. People living in deep space for that amount of time could accumulate relatively high radiation doses, officials say, and they'd have to exercise a great deal to stave off bone loss, muscle atrophy and other hazards of long-term microgravity exposure.

One possible solution is the nuclear fusion rocket being developed by Slough and his team, with funding from the NASA Innovative Advanced Concepts program, or NIAC. 

Such a system could get astronauts to the Red Planet in just 90 days or so, the researchers say. In fact, they're designing their work around a reference mission that lasts a total of 210 days — 83 days for the flight out, 30 days on the Red Planet's surface and a 97-day journey back to Earth.