Dark Energy Camera

The world’s most powerful digital camera has opened its eye and recorded the first images in hunt for dark energy (which is believed to make up 75% of the content of the Universe). Eight billion years ago, rays of light from distant galaxies began their long journey to Earth. That ancient starlight has now found its way to a mountaintop in Chile, where the newly-constructed Dark Energy Camera, the most powerful sky-mapping machine ever created, has captured and recorded it for the first time.

That light may hold within it the answer to one of the biggest mysteries in physics – why the expansion of the universe is speeding up.

Scientists in the international Dark Energy Survey collaboration recently announced that the Dark Energy Camera, the product of eight years of planning and construction by scientists, engineers, and technicians on three continents, has achieved first light. The first pictures of the southern sky were taken by the 570-megapixel camera on Sept. 12.

“The achievement of first light through the Dark Energy Camera begins a significant new era in our exploration of the cosmic frontier,” said James Siegrist, associate director of science for high energy physics with the U.S. Department of Energy. “The results of this survey will bring us closer to understanding the mystery of dark energy, and what it means for the universe.”

Full Dark Energy Camera image of the Fornax cluster of galaxies, which lies about 60 million light years from Earth. The center of the cluster is the clump of galaxies in the upper portion of the image. The prominent galaxy in the lower right of the image is the barred spiral galaxy NGC 1365. 

The Dark Energy Camera was constructed at the U.S. Department of Energy’s (DOE) Fermi National Accelerator Laboratory in Batavia, Illinois, and mounted on the Victor M. Blanco telescope at the National Science Foundation’s Cerro Tololo Inter-American Observatory (CTIO) in Chile, which is the southern branch of the U.S. National Optical Astronomy Observatory (NOAO).

With this device, roughly the size of a phone booth, astronomers and physicists will probe the mystery of dark energy, the force they believe is causing the universe to expand faster and faster.

The Dark Energy Camera is the most powerful survey instrument of its kind, able to see light from over 100,000 galaxies up to 8 billion light years away in each snapshot. The camera’s array of 62 charged-coupled devices has an unprecedented sensitivity to very red light, and along with the Blanco telescope’s large light-gathering mirror (which spans 13 feet across), will allow scientists from around the world to pursue investigations ranging from studies of asteroids in our own Solar System to the understanding of the origins and the fate of the universe.

Scientists in the Dark Energy Survey collaboration will use the new camera to carry out the largest galaxy survey ever undertaken, and will use that data to carry out four probes of dark energy, studying galaxy clusters, supernovae, the large-scale clumping of galaxies and weak gravitational lensing. This will be the first time all four of these methods will be possible in a single experiment.

The Dark Energy Survey is expected to begin in December, after the camera is fully tested, and will take advantage of the excellent atmospheric conditions in the Chilean Andes to deliver pictures with the sharpest resolution seen in such a wide-field astronomy survey. In just its first few nights of testing, the camera has already delivered images with excellent and nearly uniform spatial resolution. 

Over five years, the survey will create detailed color images of one-eighth of the sky, or 5,000 square degrees, to discover and measure 300 million galaxies, 100,000 galaxy clusters and 4,000 supernovae.

Zoomed-in image from the Dark Energy Camera of the center of the globular star cluster 47 Tucanae, which lies about 17,000 light years from Earth.

Zoomed-in image from the Dark Energy Camera of the barred spiral galaxy NGC 1365, in the Fornax cluster of galaxies, which lies about 60 million light years from Earth.

Zoomed-in image from the Dark Energy Camera of the Fornax cluster of galaxies, which lies about 60 million light years from Earth. Credit: Dark Energy Survey Collaboration. 

Full Dark Energy Camera composite image of the globular star cluster 47 Tucanae, which lies about 17,000 light years from Earth. 

Full Dark Energy Camera composite image of the Small Magellanic Cloud (a band of greenish stars running from lower left toupper right), a dwarf galaxy that lies about 200,000 light years from Earth, and is a satellite of our Milky Way galaxy.

The University of Bonn team displays the world’s largest shutter in front of the Schmidt telescope dome of the “Hoher List” Observatory. Members of the team are (from left to right) Franz-Josef Willems (mechanics) Philipp Müller (electronics design, head of the electronics lab) Martin Polder (mechanical design, head of the workshop) Klaus Reif (project management, head of the instrumentation group).

The Dark Energy Camera (DECam) mounted for testing at Fermilab’s telescope simulator.

Aerial photograph of CTIO, Cerro Tololo, Chile. Featuring Blanco 4-meter and SMARTS telescopes.