The most powerful sky-mapping machine ever created has captured and recorded light from 8 billion years ago, U.S. researchers say. After eight years of planning and construction by scientists, engineers, and technicians on three continents, the Dark Energy Camera has recorded its first images, scientists at the U.S. Department of Energy\'s Fermi National Accelerator Laboratory in Illinois reported. As part of the Dark Energy Survey, the images may help answer one of the biggest mysteries in physics -- why the expansion of the universe is speeding up. \"The achievement of \'first light\' through the Dark Energy Camera begins a significant new era in our exploration of the cosmic frontier,\" James Siegrist, associate director of science for high energy physics with the U.S. Department of Energy, said. \"The results of this survey will bring us closer to understanding the mystery of dark energy, and what it means for the universe.\" The Dark Energy Camera, about the size of a phone booth, was constructed at Fermilab. \"The Dark Energy Survey will help us understand why the expansion of the universe is accelerating, rather than slowing due to gravity,\" Brenna Flaugher, project manager and scientist at Fermilab, said. \"It is extremely satisfying to see the efforts of all the people involved in this project finally come together.\" The camera is able to see light from more than 100,000 galaxies up to 8 billion light years away in each snapshot.