The Dark Energy Camera, the first device specifically designed to search for dark energy, is on the brink of completion. Project manager Brenna Flaugher—who organized the cookout—and her colleagues are about to see the project they’ve been preparing for the past eight years transition from dream to reality. This fall, scientists will fire up DECam, as it’s affectionately known, on a mountaintop in Chile and see their hard work pay off. “It’s going to be very exciting for all of us to open the shutter for the first time,” Flaugher says. “Who knows what we’ll see?” What they hope to see are signs of the invisible, mysterious force that seems to pull the universe apart—a force that has never been directly observed. Every subsystem of the camera was rigorously tested before assembly at Fermilab last year and again once the device was completed. Dealing with what might just be the world’s most complicated digital camera, the DES team is leaving nothing to chance. As the installation process progresses, scientists and technicians have tackled a multifarious collection of tasks from coding programs to attaching cooling lines and power and data cables to the telescope’s white steel trusses.
The mystery of dark energy -- Physicists have known about cosmic expansion since the 1920s, when Edwin Hubble found that the light spectrum of distant objects was shifted to higher wavelengths in a phenomenon called redshift. But dark energy has been on their minds only since 1998, when two independent studies of type 1a supernovae revealed the bright, exploding stars to be fainter than expected, hinting that the expansion of the universe is speeding up. Scientists previously thought that, under Einstein’s Theory of General Relativity, the expansion of the universe would slow as time went on due to the pull of gravity. The 1998 finding suggested otherwise. It seems that about 5 billion years ago, the universe started expanding at an accelerating pace. Before that, gravity had been the dominant force in the universe, but then something else took over, relentlessly pushing parts of the cosmos away from one another. Theorists postulate that if we really understand how gravity works, then some unforeseen, invisible force—a dark energy—must be responsible.