NASA: Nuclear Fusion Rockets for Future Space Exploration

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.

CREDIT: University of Washington, MSNW

Rockets that harness the power of nuclear fusion may provide the next big leap in humanity's quest to explore the final frontier, NASA's science chief says.

Nuclear fusion rockets could slash travel times through deep space dramatically, potentially opening up vast swathes of the solar system to human exploration, said John Grunsfeld, associate administrator for NASA's Science Mission Directorate.

John Grunsfeld

"It's transformative," Grunsfeld said last month after his presentation at Maker Faire Bay Area in San Mateo, Calif., a two-day celebration of DIY science, technology and engineering.

"You could get to Saturn in a couple of months. How fantastic would that be?"

For a little perspective: NASA's robotic Cassini spacecraft blasted off in October 1997 and didn't enter Saturn orbit until July 2004.



Traditional chemical propulsion systems can get humans to destinations in deep space, but with a lot of travel time.

For example, a roundtrip manned mission to the vicinity of Mars, which NASA aims to execute by the mid-2030s, would require about 500 days of spaceflight.

Speeding up the trip to Mars, or anywhere else, is desirable for a number of reasons — to minimize the radiation dose astronauts receive during the journey, for example, and to save money on consumables such as food and water.

So NASA and researchers around the world have been investigating advanced propulsion technologies, including space-bending "warp drives," enormous solar sails and matter-antimatter engines.

Nuclear fusion is perhaps the most promising of these possibilities, at least in the relatively near term, proponents say.

Fusion rockets would harness the energy released when the nuclei of two or more atoms combine.

Our sun and other stars are fusion-powered, converting this energy to light; the same principle also gives hydrogen bombs their immense destructive power.

NASA has funded several early-stage fusion ideas recently via a program called NIAC (NASA Institute for Advanced Concepts).

One of these groups, led by scientists at the University of Washington, recently calculated that a fusion rocket could make it possible to get astronauts to Mars in as little as 30 days.

NASA Considers Missions for 2 Donated Spy Satellite Telescopes

The Hubble Space Telescope got one last overhaul in May 2009 by NASA astronauts on the space shuttle Atlantis and has been sending home stunning new photos ever since. 

Seen here, the iconic space telescope orbits high above the Earth, after it was released at the close of the STS-125 servicing mission to once more gaze deep into the universe.

CREDIT: NASA

NASA is sorting through a variety of possible uses for a pair of powerful spy satellite telescopes that fell into the agency's lap last year.

In November, NASA asked scientists to suggest missions for the telescopes, which were donated by the U.S. National Reconnaissance Office (NRO) and are comparable in size and appearance to the famous Hubble Space Telescope.

More than 60 serious proposals came flooding in, the most promising of which were presented in early February at the Study on Applications of Large Space Optics (SALSO) workshop in Huntsville, Ala.

"There was a lot of excitement in the scientific community when these were transferred to NASA, because they are world-class, Hubble-class telescopes, optics," said SALSO project manager George Fletcher, of NASA's Marshall Space Flight Center in Huntsville.

The two scopes were originally built to carry out surveillance missions under a multibillion-dollar NRO program called Future Imagery Architecture, but cost overruns and delays killed the program in 2005, and NASA announced in June 2012 that the NRO had bequeathed the instruments to the space agency.

While the telescopes' 8-foot-wide (2.4 meters) main mirrors are comparable to that of Hubble, the NRO instruments are designed to have a much wider field of view, NASA officials have said.

Seven big ideas
The ideas presented at the SALSO workshop fall into seven broad categories, meeting organizers and a technical review team determined:

• Mars-orbiting space telescope
• Exoplanet observatory
• General-purpose faint object explorer
• Advanced, Hubble-like visible light/ultraviolet telescope
• Optical communications node in space (which would aid transmissions to and from deep-space assets)
• Geospace dynamic observatory (which would study space weather and the sun-Earth system)
• Research of Earth's upper atmosphere (from a spot aboard the International Space Station)
• The SALSO workshop did not look into another possible use — incorporating one of the NRO scopes into NASA's proposed $1.5 billion Wide-Field Infrared Survey
• Telescope, a high-priority mission that would hunt for exoplanets and probe the mysteries of dark energy — because a separate research team is already investigating this possibility.

The SALSO workshop did not look into another possible use — incorporating one of the NRO scopes into NASA's proposed $1.5 billion Wide-Field Infrared Survey Telescope (WFIST), a high-priority mission that would hunt for exoplanets and probe the mysteries of dark energy — because a separate research team is already investigating this possibility.

The results of that second study, known as AFTA (Astrophysics Focused Telescope Assets), are downloadable. A more serious examination of the ideas presented at SALSO can now begin.