CNN  —  Imagine boarding a flight from Seattle to London, but instead of burning fossil fuel, your plane’s engine runs on fuel created — quite literally — from thin air. It sounds like science fiction, but research labs are already working on making it happen. So far it’s on a very small scale. A new class of sustainable aviation fuel (SAF) pulls carbon dioxide (CO₂) from the air and turns it into jet fuel, offering a glimpse into a future where aviation could be virtually emissions-free. The