In 2022, physicist Tammy Ma and her team achieved a scientific breakthrough decades in the making: fusion ignition, or the combining of two atoms to generate more energy out of a reaction than was put in — recreating on Earth the same process that powers the Sun. She explains how they used a giant laser (way, way bigger than you’re thinking) to catalyze this reaction and shares a vision for how this technology could change the world by creating limitless clean energy.