At about four light-years from the sun, Alpha Centauri is the closest star system to the solar system. While that may seem relatively close, it would still take humanity thousands of years to reach, based on current propulsion technology. In fact, it took Voyager 1, which was launched in 1977, 37 years to reach the outskirts of the solar system. That spacecraft flew at 17 km/sec, less than 0.006% the speed of light.
“We have to radically rethink our strategy or give up our dreams of reaching the stars in a way romanticized in books and movies,” wrote Philip Lubin, of Univ. of California, Santa Barbara’s Physics Dept.
In his paper, “A Roadmap to Interstellar Flight,” and in a video from NASA 360, Lubin states that photonic propulsion, or the propulsion of objects through light particles, could help humanity achieve quick interstellar travel, turning science fiction into science fact.
Currently, NASA estimates that it would take humans roughly six months to travel to Mars. According to Lubin, his theoretical technology could propel a 100 kg robotic craft to Mars in a few days, and a shuttle-sized craft in about one month. The former robotic craft would travel around 1,200 km/sec.
For some time, scientists have been able to reach relativistic speeds in laboratory settings on the microscopic level. But on the macroscopic level (with cars and planes and spacecraft), humans use chemical acceleration rather than electromagnetic acceleration and are “pathetically slow,” according to Lubin.
In order to bridge the divide, Lubin suggests using directed energy acceleration on a spacecraft outfitted with a laser sail.
“You’re basically pushing on a reflector; the light exerts a force; you leave your propulsion system at home. There’s nothing to spit out the exhaust pipe (be)cause there is no exhaust pipe, just a reflector and a spacecraft.” said Lubin at the 2015 NASA Innovative Advanced Concepts Fall Symposium.
“There is no known reason why we cannot do this,” Lubin said.
The initial spacecraft using this technology would be unmanned and wafer-thin, carrying out exploratory missions of nearby stars.
“While this is not the same as sending humans it is a step towards this goal and more importantly allows us to develop the relevant technological base and the ability to build a single ‘photon driver’ to send out literally millions of low mass probes in a human lifetime,” Lubin wrote in his paper.
R&D 100 AWARD ENTRIES NOW OPEN:
Establish your company as a technology leader! For more than 50 years, the R&D 100 Awards have showcased new products of technological significance. You can join this exclusive community! Learn more.