In NIF's two laser bays, 192 laser beams pick up the power they need. The beams travel a long path of about 1,000 feet, beginning in a control room where scientists create a weak laser pulse. As the beams move through a series of amplifiers, their energy increases exponentially: From beginning to end, the beams' total energy grows from one-billionth of a joule to four million joules, increasing by a factor of more than a quadrillion.

The laser beams complete the journey to the target chamber in less than 25 billionths of a second.