The world’s largest laser at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory has fired a record 1.875-megajoule shot with its 192 laser beams into the laser’s target chamber

The shot, which was just a demonstration, nonetheless represents a milepost in an effort to get past the break-even point — ignition — in coaxing fusion energy from a tiny frozen fuel pellet.

The NIF is racing to achieve ignition before the end of the fiscal year, when a two-year ignition campaign ends. A larger question for the field of laser fusion is who will support it as a possible energy source. The construction and operation of the NIF has been supported by the U.S. Nuclear Weapons Complex, which uses the facility to test the physics of nuclear bombs, and the U.S. Department of Energy’s fusion-energy budget goes almost entirely to an alternative approach that uses magnets rather than lasers to induce fusion.