A Cal Poly professor is co-developing a space exploration project that could help propel a miniature spacecraft to the next solar system within a generation.
NASA has awarded a $100,000 Innovative Advanced Concepts grant to Cal Poly statistics professor Gary Hughes and UC Santa Barbara physics professor Philip Lubin to create a preliminary model of a real idea with a science fiction feel.
Their idea is to propel into space a four-inch-square, silicon-crafted, wafer-thin vehicle at 18,282 miles per second — or one-tenth the speed of light.
The project is called Directed Energy Propulsion for Interstellar Exploration, or DEEP-IN.
The small device would be powered by energy generated from laser beams directed at mirrors on the craft’s reflective sails that are a square meter in size.
“The tiny bits of light push off the mirror as they’re reflected and propel the craft,” Hughes said. “One single ray doesn’t generate much energy, but when you throw a whole bunch of tiny ones at it, it starts to move — and since it’s small, it can move very quickly. The bigger the laser you build, the faster you go.”
According to the concept, still under development, the tiny craft would be propelled by an array of 1,000-watt Earth-orbiting lasers. The brainstorming includes possibilities of a laser array mounted on the international space station.
The lasers trained on the sails help push it to a transition point, at which time the craft essentially coasts all the way to the next star.
“Since there is little ‘friction’ in interstellar space, once the craft reaches its final speed, it will continue at that speed all the way to the next star,” Hughes said in an email.
The space vehicle could potentially reach the closest star’s solar system in the next 30 years. Proxima Centauri, the closest star to our solar system, is about 4.2 light years away, and the vehicle would need to travel at about 14 percent of the speed of light — 26,079 miles per second — to get there in 30 years.
A higher-powered propulsion system could get it there even faster, potentially in 15 years.
In comparison, the two Voyager probes, which launched in 1977, are now traveling just outside of our solar system at about 10.6 miles per second. They became the first spacecraft to reach interstellar space in 2012 and 2013, respectively. The DEEP-IN craft theoretically could reach the Voyager in a matter of weeks.
“Beyond the sun’s influence, we don’t really know what’s out there,” Hughes said. “That’s kind of fun.”
The mini spacecraft, which is envisioned to weigh about 10 grams, would have the capability to contain a camera to transmit images back to earth, as well as infrared technology and a radio transmitter.
Hughes, who has a doctorate degree in earth and planetary science from the University of Pennsylvania and industry experience designing infrared imaging systems, said that scientists have been experimenting with laser propulsion as far back as the 1970s.
In addition to the latest project, Hughes and Lubin also are developing a system that uses solar-powered lasers to combat asteroids that are on a collision course with Earth.
Their first phase of the DEEP-IN project, which began in June and extends through April, will include exploration of a mechanical design of a laser. They’ve already begun analyzing the array structure.
They plan to seek a second grant, the next phase of their project, that could provide millions of dollars in funding to conduct hardware tests and other assessments to determine the feasibility of a mission.
“NASA would love to go to the next solar system,” Hughes said. “There are many things to be learned by traveling to the next star. It fits with NASA’s exploration goals.”