Excerpts from a review of Richard Panek’s “The 4 Percent Universe: Dark Matter, Dark Energy, and the Race to Discover the Rest of Reality,” published by Houghton Mifflin Harcourt on January 10: in relating the discovery of dark matter and dark energy, the author shows how physicists and astronomers at Berkeley Lab and UC Berkeley not only contributed to the study of dark matter but pioneered the techniques that revealed the existence of dark energy. Berkeley Lab scientists remain at the forefront of research into the nature of the dark universe.

The largest image of the sky yet made – more than a trillion pixels – has been released by the multi-institutional third Sloan Digital Sky Survey (SDSS-III) at a press conference at the American Astronomical Society meeting in Seattle. The largest component of SDSS-III is the Baryon Oscillation Spectroscopic Survey, BOSS, led by Berkeley Lab scientists, now engaged in producing an even larger map of the sky.

In an attempt to explain away invisible dark matter and dark energy, some theorists have offered new theories of gravity that try to improve on Einstein’s General Theory of Relativity. A new study inspired by the work of a Berkeley Lab cosmologist indicates that at least one of these new theories is wrong.

Berkeley Lab cosmologists were part of an international team that has extended the relationship between the x-ray luminosity and the mass of galaxy clusters as measured by gravitational lensing, improving the reliability of mass measurements of much older, more distant, and smaller galactic structures. These refined measurements will benefit both the understanding of dark matter and the nature of dark energy as well.

Baryon acoustic oscillations provides a “standard ruler” for the Universe, a way to measure the details of dark energy.

Gravitational lensing, which depends on Einstein’s Theory of General Relativity, directly tests its ability to predict the growth of large-scale structure.

BOSS, the Baryon Oscillation Spectroscopic Survey, is the most ambitious attempt yet to map the expansion history of the Universe using the technique known as baryon acoustic oscillation. BOSS achieved first light on September 14 with an upgraded spectrographic system on the 2.5-meter telescope at Apache Point Observatory.

U.S. Department of Energy scientists and administrators join members of the National Science Foundation and South Dakota’s Sanford Underground Laboratory for the deepest journey yet to the proposed site of the Deep Underground Science and Engineering Laboratory (DUSEL).