Solar sails, powered only by light, could help us explore the furthest corners of our galaxy

Imagine a spacecraft propelled by nothing but light.

A massive aluminum-coated sail stretches wide, capturing the momentum from photons when they reflect off the surface. The photons' energy is transferred to the sail, slowly but surely propelling it forward. The continuous momentum allows it to soar through space, no rocket required.

Novelists, poets, and scientists have envisioned spacecraft powered by solar sails since the 1600s.

But now this fanciful concept is actually entering into reality.

NASA, the European Space Agency (ESA), the Japanese Aerospace Exploration Agency (JAXA), and The Planetary Society have all either deployed solar sail-powered spacecraft or are looking into it.

Here's how they could revolutionize space exploration.