World-first light propulsion ‘metajets’ could enable 20-year mission to Alpha Centauri

Using even the most advanced rocket propulsion technologies available today, it would take billions of dollars and hundreds of thousands of years to reach our nearest star system, Alpha Centauri. The solution to this problem may come in the form of light propulsion. One international research project, Breakthrough Starshot, announced in 2016 that it would build a lightsail probe capable of reaching Alpha Centauri within our lifetimes. Powered by millions of lasers, it could fly near the speed of light, reaching our nearest star in 20 years. While that initiative ran into funding problems—despite an initial $100 million backing by Mark Zuckerberg and others—the idea of light propulsion isn’t going away. Now, a team of scientists at Texas A&M University has demonstrated a new approach to light propulsion. Their system can lift and steer objects in multiple directions with no physical contact. The researchers believe it is more scalable than other methods, and it could one day enable a mission similar to the one proposed by Breakthrough Starshot. ‘Metajet’ experiments demonstrate full 3D maneuverability The team introduced their work in a new paper titled ‘Optical propulsion and levitation of metajets’. In it, they explained how micron-scale devices called “metajets” can generate controlled motion with the help of laser beams. The team’s metajets are composed of metasurfaces. These are ultrathin materials etched with tiny patterns. In a similar fashion to a lens, these shapes allow scientists to control the behavior of light bouncing off the devices. By carefully designing these structures, the scientists were able to control the transfer of momentum from light to an object. This allowed the object to move, showcasing a novel form of light propulsion. In a press statement , Dr. Shoufeng Lan, assistant professor and director of the Lab for Advanced Nanophotonics, compared the effect to ping pong balls bouncing off a table. Lan, who led the team, said the light acts lik…