Energy: US scientists announce historic nuclear fusion breakthrough

A target pellet inside a hohlraum capsule with laser beams entering through openings on either end. The beams compress and heat the target to the necessary conditions for nuclear fusion to occur. © Lawrence Livermore National Laboratory via AP

The US Department of Energy announced Tuesday that its researchers have achieved a "major scientific breakthrough" regarding nuclear fusion, a technology seen as a possible revolutionary alternative power source. 

Scientists have been working for decades to develop nuclear fusion – touted by its supporters as a clean, abundant and safe source of energy that could eventually allow humanity to break its dependence on the fossil fuels driving a global climate crisis.